Optoelectronic Devices

Abstract

To provide an optoelectronic device comprising a photoactive region.SOLUTION: An optoelectronic device comprises a photoactive region. The photoactive region comprises: an n-type region comprising at least one n-type layer; a p-type region comprising at least one p-type layer; and a layer of a perovskite semiconductor without any open porosity, disposed between the n-type region and the p-type region. The layer of the perovskite semiconductor forms a planar heterojunction with the n-type region or the p-type region. The perovskite semiconductor has a three-dimensional crystal structure. The perovskite semiconductor comprises at least one anion selected from halide anions. The layer of the perovskite semiconductor without any open porosity consists only of the perovskite semiconductor. The thickness of the layer of the perovskite semiconductor without any open porosity is from 10 nm to 10 μm.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an optoelectronic device, in particular to a planar junction optoelectronic device. The present invention also relates to a process for manufacturing such an optoelectronic device. [Background technology]

[0002] Thin-film photovoltaic cells are promising alternatives to their single-crystalline counterparts due to their high efficiency, comparable stability, and potentially lower manufacturing costs. The most widely studied thin-film materials currently under consideration for photovoltaic applications are the compound semiconductors CdTe [X. Wu, Solar Energy, vol. 77, p. 803, 2004], CuIn 1-x Ga x Se 2 (CIGS) [Chirila et al., Nature Materials, vol. 10, p. 857, 2011], Cu 2 ZnSnS 4 These include CIGS and CZTS [D. Barkhouse et al., Progress in Photovoltaics, vol. 20, p. 6, 2012], dye-sensitized solar cells [A. Yalla et al., Science, vol. 334, p. 629, 2011], and organic semiconductor solar cells [Y. Liang et al., Advanced Energy Materials, vol. 22, p. E135, 2010]. Inorganic compound semiconductors, including highly efficient solar cells, are typically fabricated using costly vacuum-based deposition, but recent routes towards solution processing of CIGS and CZTS have demonstrated highly efficient devices [M. Graetzel at al., Nature, vol. 488, p. 304, 2012]. Dye-sensitized solar cells and organic solar cells with low record efficiencies are typically fabricated using solution-based deposition processing procedures, but suffer from poor long-term stability. In addition, the relatively small manufacturing capabilities of tellurium and indium make CdTe and CIGS potentially commercially unattractive.

[0003] Perovskites [D. Mitzi et al., Science, vol. 267, p. 1473, 1995] are an alternative family of semiconductor materials that have been considered for device applications [D. Mitzi at al., IBM Journal of Research and Development, vol. 45, p. 29, 2001]. With regard to photovoltaic cells, perovskites have been used as sensitizers in liquid electrolyte photoelectrochemical cells [J.-H. Im et al., Nanoscale, vol. 3, p. 4088, 2011; A. Kojima et al., Journal of American Chemical Society, vol. 131, p. 6050, 2009]. However, in the previously reported electrolyte systems, the perovskite absorber rapidly decayed, and the solar cell performance decreased after only 10 minutes. Perovskites have also been used in solid-state photoelectrochemical cells [H.-S. Kim et al., Scientific Reports, doi:10.1038 / srep00591; A. Kojima et al., ECS Meeting Abstracts, vol. MA2007-02, p. 352, 2007] and as hole transporters in solid-state dye-sensitized solar cells [I. Chung, Nature, vol. 485, p. 486, 2012]. The main operating principle of dye-sensitized solar cells is that the roles of light absorption and charge transport are separated into different materials within the solar cell. This enables a light absorber, which should inefficiently generate charges when light illuminates a solid film of the material, to operate very efficiently within a dye-sensitized solar cell. Therefore, although there are examples of perovskites being used as sensitizers in mesostructured solar cells or as hole transporters in dye-sensitized solar cells, since there are no reports of solid films of perovskites operating efficiently in solar cells, it should be reasonable to assume that perovskites are not an ideal family of materials to be used as solid thin films in thin-film photovoltaics.

Prior Art Documents

Non-licensed literature

[0004] [Non-licensed document 1] X. Wu, Solar Energy, vol. 77, p.803, 2004 [Non-licensed document 2] Chirila et al., Nature Materials, vol. 10, p. 857, 2011 [Non-licensed document 3] D. Barkhouse et al., Progress in Photovoltaics, vol. 20, p. 6, 2012

Non-licensed Document 4

Non-licensed Document 5

Non-licensed Document 6

Non-licensed Document 7

Non-licensed literature 9

Non-licensed literature 10

Non-licensed Document 11

Non-licensed Document 12

Non-licensed Document 13

Non-licensed Document 14

Non-licensed Document 15

Non-licensed Document 16

Non-licensed Document 17

Non-licensed Document 18

Non-licensed Document 19

[0005] The present invention provides optoelectronic devices having a thin film of a light absorbing or emissive perovskite disposed between an n-type (electron conducting) layer and a p-type (hole conducting) layer. The inventors have unexpectedly discovered that it is possible to obtain superior device efficiency by using a dense thin film of a photoactive perovskite, as opposed to the requirement of a mesoporous composite. Although open porous perovskite structures can typically be infiltrated with p-type or n-type materials to form bulk heterojunctions with the materials, the dense perovskite layers utilized in the present invention generally form planar heterojunctions with p-type and / or n-type layers.

[0006] The perovskites utilized in the optoelectronic devices of the present invention are attractive for optoelectronic device applications because they can be formed from earth-abundant elements by both solution and vacuum processing, have tunable band structures (and hence optical and electronic properties), and can be stable in atmospheric conditions. The inventors have shown that photoactive perovskite films can be grown by solution deposition on thin scaffold or seed layers, or without such a scaffold. Devices incorporating thin seed layers can be processed in their entirety at temperatures not exceeding 150° C., which is important for reducing manufacturing costs and for enabling processing on plastic substrates to provide flexible devices, as well as processing on top of other layers to enable the fabrication of tandem and multi-junction devices. Perovskite thin films can also be effectively formed by deposition from bulk powders or by co-deposition from perovskite precursor compounds.

[0007] Accordingly, the present invention provides an optoelectronic device comprising a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; and a semiconductor layer disposed between the n-type region and the p-type region. A layer of perovskite semiconductor without open porosity Includes.

[0008] Typically, the optoelectronic device is a photovoltaic device.

[0009] Alternatively, the optoelectronic device may be other than a photovoltaic device. The optoelectronic device may be, for example, a light emitting device.

[0010] In some embodiments, the photoactive region comprises: the n-type region; The p-type region and a semiconductor layer disposed between the n-type region and the p-type region. (i) a first layer comprising a scaffold material and a perovskite semiconductor; (ii) a capping layer disposed on the first layer, the capping layer being the layer of a perovskite semiconductor without open pores; and Including, The perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer.

[0011] In another aspect, the present invention provides a process for manufacturing an optoelectronic device comprising a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; and a semiconductor layer disposed between the n-type region and the p-type region. a layer of a perovskite semiconductor without open pores; The process includes: (a) providing a first region; (b) disposing a second region on the first region, the second region comprising a layer of a perovskite semiconductor without open pores; (c) disposing a third region over the second region; Including, the first region is an n-type region including at least one n-type layer and the third region is a p-type region including at least one p-type layer; or The first region is a p-type region including at least one p-type layer, and the third region is an n-type region including at least one n-type layer.

[0012] Typically, the process of the present invention is for producing a photovoltaic device comprising said photoactive region.

[0013] Alternatively, the process can be used to fabricate optoelectronic devices other than photovoltaic devices, which optoelectronic devices include the photoactive region. The process can be used, for example, to fabricate light-emitting devices that include the photoactive region.

[0014] In some embodiments of the process of the present invention, the photoactive region comprises the n-type region, the p-type region, and a photoactive region disposed between the n-type region and the p-type region. (i) a first layer comprising a scaffold material and a perovskite semiconductor; (ii) a capping layer disposed on the first layer, the capping layer being the layer of perovskite semiconductor without open pores, the perovskite semiconductor in the capping layer being in contact with the perovskite semiconductor in the first layer; Includes.

[0015] In such an embodiment, the process of the present invention comprises: (a) providing the first region; (b) disposing the second region over the first region, the second region comprising: (i) a first layer comprising a scaffold material and a perovskite semiconductor; (ii) a capping layer on said first layer, the capping layer being said layer of perovskite semiconductor without open pores, the perovskite semiconductor in the capping layer being in contact with the perovskite semiconductor in the first layer; a placing step including: (c) disposing the third region over the second region; Includes.

[0016] The present invention further provides an optoelectronic device obtainable by the inventive process for manufacturing an optoelectronic device.

[0017] Typically, the optoelectronic device is a photovoltaic device.

[0018] Alternatively, the optoelectronic device may be other than a photovoltaic device. The optoelectronic device may be, for example, a light emitting device. [Brief description of the drawings]

[0019] [Figure 1](a) General structure of an embodiment of the optoelectronic device of the present invention, and (b) schematic diagram of a photovoltaic cell (a modified example in which a thin Al2O3 layer or TiO2 layer is omitted was also considered) exemplified in this specification. At least one of the metal electrodes is translucent from the visible region to the near-infrared region of the solar spectrum. The translucency typically has a transmittance of 80%, and a transmittance in the range from 40 to 90%. [Diagram 2] (a) XRD (X-ray diffraction) spectra of perovskite films grown on top of each of the lower layer modified examples considered in the following examples in this specification, and (b) diagram of XRD spectra of perovskite formed by vapor deposition. [Diagram 3] Diagram of the normalized UV-visible spectra of perovskite films grown on top of each of the lower layer modified examples considered in the following examples in this specification. [Figure 4] (a) Representative J-V characteristics diagrams of devices using HT B-Al2O3, (b) HT B-TiO2, (c) HT Al2O3, (d) HT TiO2, (e) HT C, (f) LT Al2O3, (g) LT TiO2, and (i) a modified example of vapor deposition type. [Diagram 5] (a) SEM (Scanning electron microscopy) micrographs of cross-sections of solar cells using modified examples of HT B-Al2O3, (b) HT B-TiO2, (c) HT Al2O3, (d) HT TiO2, (e) HT C, and (f) LT C. [Figure 6] (a) Planar SEM micrographs seen from above of substrate treatments using modified examples of HT B-Al2O3, (b) HT B-TiO2, (c) HT Al2O3, (d) HT TiO2, (e) HT C, and (f) LT C. [Figure 7] (a) Planar SEM micrographs of substrate treatments using modified examples of LT Al2O3 and (b) LT TiO2. [Figure 8] Schematic diagram of an element for an inverted p-i-n type thin film solar cell. [Figure 9]Steady-state photoluminescence spectra for a bilayer of perovskite absorber on a) a p-type layer and b) an n-type layer. The emission is centered on the photoluminescence peak of the perovskite absorber CH3NH3PbI3-xClx. [Figure 10] a) SEM cross-sectional image of the optimized inverted device configuration. The scale bar represents 250 nm. The different layers are colored according to the color scheme of the device schematic shown in b). [Figure 11] SEM top views of the substrates followed by the perovskite layer for substrates containing a) and c) PEDOT:PSS annealed for 20 min at 150 °C and b) and d) PEDOT:PSS crosslinked with a 0.25 M aqueous solution of FeCl3. The scale bars in a) and c) correspond to 25 μm and in b) and d) correspond to 2.5 μm. [Figure 12] a) JV curves and b) absorption spectra for typical devices composed of both crosslinked (circles) and annealed (squares) PEDOT:PSS layers. The inset table shows the short circuit current density (Jsc, mAcm-2), power conversion efficiency (Eff, %), open circuit voltage (Voc, V) and fill factor (FF) for typical devices of both architectures. [Figure 13] SEM images of the top view of the substrate with a perovskite layer formed on top and after deposition of a) and c) NiO, and b) and d) V2O5. The scale bars in a) and b) correspond to 25 μm and in c) and d) correspond to 2.5 μm. [Figure 14] FIG. 13 shows JV curves from devices containing vanadium oxide (squares) and NiO (circles) p-type contacts. [Figure 15]a) Time evolution of the JV curves from the same device upon illumination. Scans were performed every minute, with the first scan at the bottom and the last scan at the top. b) JV curves for the champion device in the normal configuration (triangles) and in our inverted configuration (circles). The inset table shows the short circuit current density (Jsc, mAcm-2), power conversion efficiency (Eff, %), open circuit voltage (Voc, V) and fill factor (FF) for both device architectures. [Figure 16] Schematic of a hybrid tandem solar cell architecture where a c-Si HIT (Heterojunction with Intrinsic Thin layer) cell is used as the back cell in a tandem junction, where i = intrinsic, a = amorphous, c = crystalline, TCO = transparent conducting oxide. Sunlight enters from the top. [Figure 17] Schematic of a hybrid tandem solar cell architecture, where a perovskite solar cell is used as the top cell and a conventional thin-film solar cell as the back cell in a tandem junction, where TCO = transparent conducting oxide. Especially with the current generation of thin-film technologies (e.g. GIGS solar cells), there is a need to realize "inverted" perovskite solar cells for monolithic two-terminal tandem devices. Sunlight is incident from the top. [Figure 18] Photograph of the deposition chamber for dual-source vapor deposition of perovskites. [Figure 19] Schematic diagram of the dual source deposition chamber. [Figure 20] a) Completed dual-source deposition-type perovskite solar cell, b) illustration of the cross-sectional image, c) cross-sectional SEM image of the completed device. [Figure 21]a) Processed sample on FTO (fluorine-doped tin oxide) coated glass with only a dense TiO2 layer and spin-coated perovskite; b, c) surface SEM images of the spin-coated perovskite; d) FTO coated glass and sample with only a dense TiO2 layer and evaporated perovskite; e, f) surface SEM images of the evaporated perovskite. [Figure 22] Figure 1. J-V curve of the best dual-source evaporated perovskite solar cell measured under 100mW cm-2 artificial AM1.5 sunlight. The inset gives the solar cell performance parameters derived from this J-V curve. [Figure 23] FIG. 1 shows XRD measurements of evaporated perovskite compared to spin-coated perovskite (designated K330), methylammonium iodide (MAI), lead iodide (PbI2), and TiO2 coated FTO glass. [Figure 24] FIG. 1 shows a comparison of absorbance for 200 nm thick films of evaporated and spin-coated perovskite. [Diagram 25] Comparison between unannealed and annealed perovskite layers deposited by two-source vapor deposition: left: unannealed evaporated perovskite surface (as-deposited); right: annealed evaporated perovskite surface (after annealing at 100 degrees Celsius for 45 min in a nitrogen glove box). [Figure 26] Comparison of surface coverage by two-source vapor and solution deposition. Left: evaporated and annealed perovskite film; Right: spin-coated and annealed perovskite film coated on glass / FTO / dense TiO2. [Figure 27] Comparison between SEM cross-sectional images: Left: two-source evaporated flat junction element; Right: spin-coated flat junction element. [Figure 28]Figure 1 shows an XRD comparison between perovskite layers formed by two-source vapor deposition and by spin-coating of perovskite precursor solutions. For both films, the starting precursors were MAI and PbCl2. [Figure 29] Cross-sectional scanning electron micrographs of devices showing (from bottom to top) the glass substrate, FTO, TiO2 electron selective layer, photoactive layer, and spiro-OMeTAD. The photoactive layer is (a) PbCl2 and (b) CH3NH3PbI3-xClx after dip-coating a PbCl2 film in a propan-2-ol solution of CH3NH3I. [Diagram 30] Cross-sectional scanning electron micrographs of the device showing (from bottom to top) the glass substrate, FTO, TiO2 electron selective layer, photoactive layer, and spiro-OMeTAD. The photoactive layer is (a) PbI2 and (b) CH3NH3PbI3 after dip-coating a PbI2 film in a propan-2-ol solution of CH3NH3I. [Diagram 31] X-ray diffraction spectra of thin films of (a) PbCl2, (b) CH3NH3PbI3-xClx, (c) PbI2, and (d) CH3NH3PbI3. After dip-coating, the films from the two precursors show a relative decrease in intensity of the peaks corresponding to the precursor lattice and a relative increase of the perovskite lattice (without the precursor XRD spectrum), indicating predominant conversion of the precursor films to perovskite. [Diagram 32] Current density-voltage characteristics of a device made with PbI2 as active layer (dashed line) and a device in which PbI2 was deposited and converted to CH3NH3PbI3 by dip-coating in a solution of methylammonium iodide in propan-2-ol (solid line). Performance parameters for PbI2 are Jsc=1.6mA / cm2, PCE=0.80%, Voc=0.97V, FF=0.57. Performance parameters for CH3NH3PbI3 are Jsc=5.3mA / cm2, PCE=2.4%, Voc=0.82V, FF=0.61. [Diagram 33]Current density-voltage characteristics of devices made with PbCl2 as active layer (dashed line) and devices where evaporated PbCl2 was converted to CH3NH3PbI3-xClx by dip-coating in a solution of methylammonium iodide in propan-2-ol (solid line). Performance parameters for PbCl2 are Jsc=0.081mA / cm2, PCE=0.006%, Voc=0.29V, FF=0.27. Performance parameters for CH3NH3PbI3-xClx are Jsc=19.0mA / cm2, PCE=7.0%, Voc=0.80V, FF=0.49. [Diagram 34] Photoluminescence measurements and fitting to a diffusion model for mixed halide organolead trihalide perovskite films CH3NH3PbI3-xClx and triiodide perovskite films CH3NH3PbI3 in the presence of p-type or n-type quenchers. Time-resolved PL measurements were taken at the peak emission wavelength of the mixed halide perovskite with electron (PCBM; triangles) or hole (spiro-OMeTAD; circles) quencher layers, with a stretched exponential fit to the data for insulating PMMA-coated films (black squares) and fitting to the quenched samples using the diffusion model described in the text. A pulsed (0.3 to 10 MHz) excitation source at 507 nm with a fluence of 30 nJ / cm2 was impinged on the glass substrate side. Inset in FIG. 34: Comparison of the PL decay of the two perovskites (with PMMA coating) with lifetime τe shown as the time it takes to reach 1 / e of the initial intensity on a longer time scale. [Diagram 35]Photoluminescence measurements and fitting to a diffusion model for organolead triiodide perovskite films CH3NH3PbI in the presence of p-type or n-type quenchers. Time-resolved PL measurements were taken at the peak emission wavelength of mixed halide perovskite with electron (PCBM; triangles) or hole (spiro-OMeTAD; circles) quencher layers, with a stretched exponential fit to the data for insulating PMMA-coated films (black squares) and fitting to the quenched samples using the diffusion model described in the text. A pulsed (0.3 to 10 MHz) excitation source at 507 nm with a fluence of 30 nJ / cm2 was impinged on the glass substrate side. [Diagram 36] 1 is a cross-sectional SEM image of a 270 nm thick mixed halide absorber layer with a top hole quenching layer of spiro-OMeTAD. [Figure 37] FIG. 1 shows photoluminescence decay for PMMA-coated mixed halide organolead trihalide perovskite films CH3NH3PbI3-xClx (black squares) and organolead triiodide perovskite films CH3NH3PbI3 (grey squares), with lifetime τe shown as the time it takes to reach 1 / e of the initial intensity. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The present invention provides an optoelectronic device comprising a photoactive region comprising an n-type region comprising at least one n-type layer, a p-type region comprising at least one p-type layer, and a layer of a perovskite semiconductor without open pores disposed between the n-type and p-type regions.

[0021] The term "photoactive region," as used herein, refers to a region within an optoelectronic device that accepts electrical charges, both electrons and holes, that can either (i) absorb light and subsequently generate free charge carriers, or (ii) subsequently recombine and emit light.

[0022] The term "semiconductor," as used herein, refers to a material that has an electrical conductivity that is intermediate in magnitude between that of a conductor and that of a dielectric. Semiconductors can be n-type, p-type, or intrinsic semiconductors.

[0023] As used herein, the term "n-type region" refers to a region of one or more electron-transporting (i.e., n-type) materials. Similarly, the term "n-type layer" refers to a layer of an electron-transporting (i.e., n-type) material. An electron-transporting (i.e., n-type) material can be a single electron-transporting compound or elemental material, or a mixture of two or more electron-transporting compounds or elemental materials. An electron-transporting compound or elemental material can be undoped or doped with one or more dopant elements.

[0024] As used herein, the term "p-type region" refers to a region of one or more hole-transporting (i.e., p-type) materials. Similarly, the term "p-type layer" refers to a layer of a hole-transporting (i.e., p-type) material. A hole-transporting (i.e., p-type) material may be a single hole-transporting compound or elemental material, or a mixture of two or more hole-transporting compounds or elemental materials. A hole-transporting compound or elemental material may be undoped or doped with one or more dopant elements.

[0025] The term "perovskite" as used herein means CaTiO 3 where the layer is CaTiO 3 It has a structure related to that of CaTiO 3 The structure of the compound is shown by the chemical formula ABX 3where A and B are cations of different sizes and X is an anion. In the unit cell, the A cation is at (0,0,0), the B cation is at (1 / 2,1 / 2,1 / 2), and the X anion is at (1 / 2,1 / 2,0). The A cation is usually larger than the B cation. As A, B, and X are varied, different ion sizes are obtained, as in CaTiO 3 Those skilled in the art will recognize that the structure of a perovskite material may be modified away from the structure adopted by CaTiO to a modified structure of lower symmetry. 3 The symmetry would also be lower if the material contained layers having structures related to those of the perovskite material. Materials containing layers of perovskite materials are well known. For example, 2 NiF 4 The structure of the material with the type structure includes a layer of perovskite material. Perovskite material is a material with the chemical formula [A][B][X] 3 A person skilled in the art will recognize that the perovskite can be represented by the formula: where [A] is at least one cation, [B] is at least one cation, and [X] is at least one anion. When the perovskite contains more than one A cation, the different A cations can be distributed throughout the A sites in a regular or irregular manner. When the perovskite contains more than one B cation, the different B cations can be distributed throughout the B sites in a regular or irregular manner. When the perovskite contains more than one X anion, the different X anions can be distributed throughout the X sites in a regular or irregular manner. The symmetry of perovskites containing more than one A cation, more than one B cation, or more than one X cation can be represented by the formula: CaTiO 3 The symmetry of

[0026] As mentioned in the previous paragraph, the term "perovskite", as used herein, refers to: (a) CaTiO 3or (b) a material that includes a layer of material, where the layer is CaTiO 3 Although both these categories of perovskites can be used in the device according to the invention, it is preferred in some circumstances to use perovskites of the first category, (a), i.e. perovskites with a three-dimensional (3D) crystal structure. Such perovskites typically comprise a 3D network of perovskite unit cells without any separation between the layers. The second category of perovskites, (b), on the other hand, comprises perovskites with a two-dimensional (2D) layered structure. Perovskites with a 2D layered structure can comprise layers of perovskite unit cells separated by (sandwiched) molecules; an example of such a 2D layered perovskite is [2-(1-cyclohexenyl)ethylammonium]. 2 PbBr 4 2D layered perovskites tend to have high exciton binding energies, which favor the generation of bound electron-hole pairs (excitons) under photoexcitation, rather than free charge carriers. The bound electron-hole pairs may not be sufficiently mobile to reach the p-type or n-type contacts where they can be converted (ionized) and generate free charge. As a result, to generate free charge, the exciton binding energy must be overcome, which represents an energy cost to the charge generation process and results in lower voltages and lower efficiencies in photovoltaic cells. In contrast, perovskites with 3D crystal structures tend to have much lower exciton binding energies (on the order of thermal energy), and are therefore capable of generating free carriers immediately following photoexcitation. Thus, the perovskite semiconductors utilized in the devices and processes of the present invention are preferably perovskites of the first category, (a), i.e., perovskites with three-dimensional crystal structures. This is particularly preferred when the optoelectronic device is a photovoltaic device.

[0027] Within said layer of perovskite semiconductor without open pores, the perovskite semiconductor utilised in the present invention is typically a perovskite semiconductor capable of (i) absorbing light, thereby generating free charge carriers, and / or (ii) emitting light by accepting charges, both electrons and holes, which subsequently recombine and emit light. Thus, the perovskite utilised is typically a light absorbing and / or emitting perovskite.

[0028] As will be appreciated by those skilled in the art, within said layer of perovskite semiconductor without open pores, the perovskite semiconductor utilized in the present invention may be a perovskite that acts as an n-type electron transporting semiconductor when photodoped. Alternatively, it may be a perovskite that acts as a p-type hole transporting semiconductor when photodoped. Thus, the perovskite may be an n-type, p-type, or intrinsic semiconductor. In a preferred embodiment, the perovskite utilized is a perovskite that acts as an n-type electron transporting semiconductor when photodoped.

[0029] Typically, the perovskite semiconductors used in the present invention are photosensitizing materials, i.e. materials that are capable of both emitting light and transporting charge (electrons or holes).

[0030] As used herein, the term "porous" refers to a material having pores arranged therein. Thus, for example, in a porous scaffold material, the pores are the volume within the scaffold that is free of scaffold material. The individual pores may be of the same size or of different sizes. The size of the pores is defined as the "pore size." The critical size of a pore is the size of the smallest dimension of the pore, which, for most phenomena involving porous solids, in the absence of further precision, is the width of the pore (i.e., the width of a slit-shaped pore, the diameter of a cylindrical or spherical pore, etc.). To avoid misinterpretation of the change in scale when comparing cylindrical pores with slit-shaped pores, the diameter of the cylindrical pore (rather than the radius of the cylindrical pore) should be used as the "pore width" (J. Rouquerol et al., "Recommendations for the Characterization of Porous Solids", Pure & Appl. Chem., Vol. 66, No. 8, pp. 1739-1758, 1994). The following distinctions and definitions were adopted in previous IUPAC documents (KSW Sing, et al., Pure and Appl. Chem., vol. 57, n04, pp. 603-919, 1985; and IUPAC "Manual on Catalyst Characterization", J. Haber, Pure and Appl. Chem., vol. 63, pp. 1227-1246, 1991): - Micropores have a width (ie, pore size) of less than 2 nm. -Mesopores have a width (i.e. pore size) ranging from 2 nm to 50 nm. - Macropores have a width (ie, pore size) greater than 50 nm.

[0031] Porosity in a material can include "closed" pores as well as open pores. Closed pores are pores in a material that are disconnected cavities, i.e., pores that are isolated within the material and are not connected to any other pores, and therefore cannot be accessed by fluids (e.g., liquids such as solutions) to which the material is exposed. On the other hand, "open pores" should be accessible by such fluids. The concepts of open and closed pores are discussed in detail in J. Rouquerol et al., "Recommendations for the Characterization of Porous Solids", Pure & Appl. Chem., Vol. 66, No. 8, pp. 1739-1758, 1994.

[0032] Open porosity therefore refers to the fraction of the total volume of a porous material through which fluid flow can effectively occur. It therefore excludes closed porosity. The term "open porosity" is interchangeable with the terms "connected porosity" and "effective porosity" and is generally shortened in the art to simply "pores". (In the optoelectronic device of the present invention, a perovskite semiconductor present in a "layer of perovskite semiconductor without open porosity" therefore cannot be referred to as a "porous perovskite".

[0033] The term "without open pores", as used herein, therefore, refers to a material that is effectively free of pores.

[0034] The optoelectronic device of the present invention includes a layer of perovskite semiconductor that is free of open pores. The layer, and the perovskite semiconductor therein, is free of open pores. Thus, the perovskite semiconductor in the layer is not permeated by either n-type material or n-type material in the n-type regions, nor by either p-type material or p-type material in the p-type regions. Rather, the perovskite semiconductor in the layer typically forms a planar heterojunction with the n-type or p-type regions, or in some cases with both the n-type and p-type regions.

[0035] Also, when a layer of a perovskite semiconductor without open porosity is a "capping layer" disposed on a first layer comprising a scaffold material and a perovskite semiconductor, the capping layer is not infiltrated by any of the scaffold material because the capping layer and the perovskite semiconductor therein are without open porosity. The perovskite in the first layer, on the other hand (which is generally the same perovskite compound as the perovskite compound in the capping layer), is typically disposed within the pores of the scaffold material and is therefore sometimes said to be "infiltrated" by the scaffold material.

[0036] In some embodiments of the optoelectronic device of the present invention, the layer of perovskite semiconductor without open pores is non-porous. The term "non-porous" as used herein refers to a material that does not have any pores, i.e., no open pores and also no closed pores.

[0037] Generally, the layer of perovskite semiconductor without open pores consists essentially of perovskite semiconductor. Perovskites are crystalline compounds. Thus, the layer of perovskite semiconductor without open pores typically consists essentially of perovskite crystallites. In some embodiments, the layer of perovskite semiconductor without open pores consists of perovskite semiconductor. Thus, the layer of perovskite semiconductor without open pores typically consists of perovskite crystallites.

[0038] The layer of open pore free perovskite semiconductor is generally in contact with at least one of the n-type or p-type regions.

[0039] A layer of perovskite semiconductor without open pores typically forms a planar heterojunction with an n-type region or a p-type region. Either an n-type region or a p-type region can be disposed on a layer of perovskite semiconductor without open pores, but as noted above, because the layer of perovskite semiconductor has no open pores, the n-type or p-type material does not infiltrate the perovskite semiconductor to form a bulk heterojunction, but rather typically forms a planar heterojunction with the perovskite semiconductor. Typically, a layer of perovskite semiconductor without open pores forms a planar heterojunction with the n-type region.

[0040] In some embodiments, the layer of perovskite semiconductor without open pores is in contact with both the n-type region and the p-type region. In such embodiments, there will be no other layer (such as a "first layer" including a scaffold material and a perovskite semiconductor) separating the layer of perovskite semiconductor without open pores from the n-type region or the p-type region. As noted above, since the layer of perovskite semiconductor is without open pores, in such embodiments, neither the n-type region material nor the p-type region material infiltrates the perovskite semiconductor to form a bulk heterojunction, but rather typically forms a planar heterojunction with the perovskite semiconductor. In this way, the layer of perovskite semiconductor without open pores can form a planar heterojunction with both the n-type region and the p-type region on either side of the layer. Thus, in some embodiments of the optoelectronic device of the present invention, the layer of perovskite semiconductor forms a first planar heterojunction with the n-type region and a second planar heterojunction with the p-type region.

[0041] The optoelectronic devices of the present invention are typically thin film devices.

[0042] Typically, the thickness of the layer of the perovskite semiconductor without open pores is from 10 nm to 100 μm. More typically, the thickness of the layer of the perovskite semiconductor without open pores is from 10 nm to 10 μm. Preferably, the thickness of the layer of the perovskite semiconductor without open pores is from 50 nm to 1000 nm, for example from 100 nm to 700 nm. The thickness of the layer of the perovskite semiconductor is often greater than 100 nm. The thickness can be, for example, from 100 nm to 100 μm, or, for example, from 100 nm to 700 nm.

[0043] To provide a highly efficient photovoltaic device, the absorption of the absorber / photoactive region should ideally be maximized to generate an optimal amount of current. As a result, when using perovskites as absorbers in solar cells, the thickness of the perovskite layer should ideally be on the order of 300 to 600 nm to absorb most of the sunlight across the entire visible spectrum. In particular, in solar cells, the perovskite layer should generally be thicker than the absorption depth (defined as the film thickness required to absorb 90% of the incident light of a given wavelength, which is typically greater than 100 nm for the perovskite materials of interest if significant light absorption is required across the entire visible spectrum (400 to 800 nm)), since the use of a photoactive layer in a photovoltaic device with a thickness of less than 100 nm can be detrimental to the device's performance.

[0044] In contrast, electroluminescent (light-emitting) devices do not need to absorb light and are therefore not constrained by absorption depth. Moreover, in practice, the p-type and n-type contacts of an electroluminescent device are typically selected such that once electrons or holes are injected into one side of the device, they do not flow out the other, regardless of the thickness of the photoactive layer (i.e., the contacts are selected to inject or collect only one carrier). In essence, charge carriers are blocked from migrating out of the photoactive region, which would otherwise be available to recombine and generate photons, and thus extremely thin photoactive regions can be utilized.

[0045] Typically, therefore, when the optoelectronic device is a photovoltaic device, the thickness of the layer of the perovskite semiconductor is greater than 100 nm. The thickness of the layer of the perovskite semiconductor in the photovoltaic device can be, for example, 100 nm to 100 μm, or, for example, 100 nm to 700 nm. The thickness of the layer of the perovskite semiconductor in the photovoltaic device can be, for example, 200 nm to 100 μm, or, for example, 200 nm to 700 nm.

[0046] As used herein, the term "thickness" refers to the average thickness of a component of an optoelectronic device.

[0047] The inventors have shown that a thin scaffold can be used to seed the growth of a photoactive perovskite layer in which the majority of the photoactivity (e.g. light absorption) occurs within a capping layer that forms above the scaffold, the capping layer being a layer of perovskite semiconductor without open pores, and in these examples a "first layer" that separates the capping layer from either the n-type or p-type region.

[0048] Thus, in some embodiments, the photoactive region of the device comprises: the n-type region; The p-type region and a semiconductor layer disposed between the n-type region and the p-type region. (i) a first layer comprising a scaffold material and a perovskite semiconductor; (ii) a capping layer disposed on the first layer, the capping layer being the layer of a perovskite semiconductor without open pores; and Includes.

[0049] The perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer.

[0050] Since the perovskite in the first layer and the perovskite in the capping layer are often deposited together in the same step, typically by the same solution or vapor deposition step, the perovskite semiconductor in the capping layer is usually made from the same perovskite compound as the perovskite semiconductor in the first layer.

[0051] Unlike the first layer, which includes both a scaffold material and a perovskite semiconductor, the capping layer does not include a scaffold material. As explained above, the capping layer, which is the layer of perovskite semiconductor without open pores, typically consists essentially of or consists of microcrystals of the perovskite semiconductor. The capping layer is therefore usually composed essentially of the perovskite semiconductor. In some embodiments, the capping layer consists of the perovskite semiconductor.

[0052] The first layer comprises the scaffold material and the perovskite semiconductor disposed on the surface of the scaffold material. The term "scaffold material" as used herein refers to a material whose function includes serving as a physical support for another material. In the present case, the scaffold material serves as a support for the perovskite semiconductor present in the first layer. The perovskite semiconductor is disposed on or supported on the surface of the scaffold material. The scaffold material is usually porous, meaning that it typically has an open pore structure. Thus, the "surface" of the scaffold material herein typically refers to the surface of the pores in the scaffold material. Thus, the perovskite semiconductor in the first layer is typically deposited on the surface of the pores in the scaffold material.

[0053] In some embodiments, the scaffold material is porous and the perovskite semiconductor in the first layer is deposited within the pores of the scaffold material. The effective porosity of the scaffold material is typically at least 50%. For example, the effective porosity can be about 70%. In one embodiment, the effective porosity is at least 60%, e.g., at least 70%.

[0054] The scaffold material is usually mesoporous. The term "mesoporous" as used herein means that the pores within the material have an average pore size of 2 nm to 50 nm. The individual pores may be of different sizes and any shape.

[0055] Alternatively, the scaffolding material may be macroporous. The term "macroporous" as used herein means that the average pore size of the pores within the material is greater than 2 nm. In some examples, the pore size within the scaffolding material, when macroporous, is greater than 2 nm and less than or equal to 1 μm, or, for example, greater than 2 nm and less than or equal to 500 nm, more preferably greater than 2 nm and less than or equal to 200 nm.

[0056] The scaffold material can be a charge transporting scaffold material (e.g., an electron transporting material such as titania, or alternatively a hole transporting material), or a dielectric material such as alumina. The term "dielectric material" as used herein refers to a material that is an electrical insulator or a very poor conductor of electric current. The term dielectric therefore excludes semiconducting materials such as titania. The term dielectric as used herein typically refers to a material that has a band gap of 4.0 eV or greater. (The band gap of titania is about 3.2 eV.) Those skilled in the art can easily measure the band gap of a semiconductor by using well-known procedures that do not require undue experimentation. For example, it is possible to estimate the band gap of a semiconductor by making a photovoltaic diode or solar cell from the semiconductor and determining the photovoltaic action spectrum. The monochromatic photon energy at which photocurrent begins to be generated by the diode can be taken as the band gap of the semiconductor, and such a method was used by Barkhouse et al., Prog. Photovolt: Res. Appl. 2012; 20:6-11. References herein to the band gap of a semiconductor mean the band gap as measured by this method, i.e., the band gap as determined by recording the photovoltaic action spectrum of a photovoltaic diode or solar cell made from the semiconductor and observing the monochromatic photon energy at which significant photocurrent begins to be generated.

[0057] Typically, the perovskite semiconductor in the first layer (which also includes a scaffold material) is in contact with one of the p-type and n-type regions and the perovskite semiconductor in the capping layer is in contact with the other of the p-type and n-type regions. Typically, the perovskite semiconductor in the capping layer forms a planar heterojunction with the region it is in contact with, i.e., with either the p-type or the n-type region.

[0058] In a preferred embodiment, the perovskite semiconductor in the capping layer contacts the p-type region and the perovskite semiconductor in the first layer contacts the n-type region. Typically, in this embodiment, the scaffold material is either an electron transport scaffold material or a dielectric scaffold material. Typically, the perovskite semiconductor in the capping layer forms a planar heterojunction with the p-type region.

[0059] In another embodiment, the perovskite semiconductor in the capping layer contacts the n-type region and the perovskite semiconductor in the first layer contacts the p-type region, however. Typically, in this embodiment, the scaffold material is a hole transport scaffold material or a dielectric scaffold material. Typically, the perovskite semiconductor in the capping layer forms a planar heterojunction with the n-type region.

[0060] The thickness of the capping layer is typically greater than the thickness of the first layer, and most of the photoactivity (e.g., light absorption) therefore typically occurs within the capping layer.

[0061] The thickness of the capping layer is typically from 10 nm to 100 μm. More typically, the thickness of the capping layer is from 10 nm to 10 μm. Preferably, the thickness of the capping layer is from 50 nm to 1000 nm, or such as from 100 nm to 700 nm.

[0062] The thickness of the capping layer may be, for example, from 100 nm to 100 μm, or such as from 100 nm to 700 nm. Capping layers having a thickness of at least 100 nm are usually preferred.

[0063] The thickness of the first layer, on the other hand, is often from 5 to 1000 nm. More typically, the thickness of the first layer is from 5 to 500 nm, or such as from 30 to 200 nm.

[0064] The perovskite semiconductors utilised in the present invention in the layer of perovskite semiconductor without open pores, and in the first layer, when present, are typically capable of (i) absorbing light, thereby generating free charge carriers, and / or (ii) emitting light by accepting charges, both electrons and holes, which subsequently recombine and emit light.

[0065] As such, the perovskites utilised are typically light absorbing and / or light emitting perovskites.

[0066] Perovskites are usually light absorbing materials. Typically, perovskites are utilized that can absorb light having a wavelength between 300 nm and 2000 nm (i.e., perovskites that can absorb light having a wavelength anywhere within this range). More typically, the perovskites utilized are those that can absorb light having a wavelength within the range of 300 to 1200 nm, or, for example, those that can absorb light having a wavelength between 300 and 1000 nm. More typically, the perovskites utilized are those that can absorb light having a wavelength anywhere within the range of 300 to 800 nm.

[0067] The perovskite semiconductors utilized in the optoelectronic devices of the present invention preferably have a band gap narrow enough to allow excitation of electrons by incident light. In particular, when the optoelectronic device is a photovoltaic device, a band gap of 3.0 eV or less is particularly preferred, since such a band gap is low enough for sunlight to excite electrons throughout the photovoltaic device. Certain perovskites, including some oxide perovskites and 2D layered perovskites, have band gaps wider than 3.0 eV and are therefore less preferred for use in photovoltaic devices than perovskites having band gaps of 3.0 eV or less. Such perovskites include CaTiO 3 , SrTiO 3 and CaSrTiO 3:Pr 3+ It contains these, each of which has a band gap around 3.7 eV, 3.5 eV, and 3.5 eV respectively.

[0068] Therefore, the perovskite semiconductor used in the optoelectronic device of the present invention typically has a band gap of 3.0 eV or less. In some embodiments, the band gap of the perovskite is 2.8 eV or less, for example, 2.5 eV or less. The band gap may be, for example, 2.3 eV or less, or for example 2.0 eV or less.

[0069] Generally, the band gap is at least 0.5 eV. Thus, the band gap of the perovskite may be from 0.5 eV to 2.8 eV. In some embodiments, the band gap is from 0.5 eV to 2.5 eV, or for example, from 0.5 eV to 2.3 eV. The band gap of the perovskite may be, for example, from 0.5 eV to 2.0 eV. In another embodiment, the band gap of the perovskite may be from 1.0 eV to 3.0 eV, or for example, from 1.0 eV to 2.8 eV. In some embodiments, the band gap of the perovskite is from 1.0 eV to 2.5 eV, or for example, from 1.0 eV to 2.3 eV. The band gap of the perovskite semiconductor may be, for example, from 1.0 eV to 2.0 eV.

[0070] The band gap of the perovskite is more typically from 1.2 eV to 1.8 eV. The band gap of the organometallic halide perovskite semiconductor is typically within this range, for example, it may be about 1.5 eV or about 1.6 eV. Thus, in one embodiment, the band gap of the perovskite is from 1.3 eV to 1.7 eV.

[0071] The perovskite semiconductor used in the optoelectronic device of the present invention typically contains at least one anion selected from halide anions and chalcogenide anions.

[0072] The term "halide" refers to an anion of a Group 7 element, i.e., a halogen. Typically, halide refers to a fluoride, chloride, bromide, iodide, or astatide anion. The term "chalcogenide anion," as used herein, refers to an anion of a Group 6 element, i.e., a chalcogen. Typically, chalcogenide refers to an oxide, sulfide, selenide, or telluride anion.

[0073] In the optoelectronic devices of the present invention, the perovskite often comprises a first cation, a second cation, and said at least one anion.

[0074] As one of ordinary skill in the art will recognize, perovskites can include more cations or more anions. For example, perovskites can include two, three, or four different first cations; two, three, or four different second cations; or two, three, or four different anions.

[0075] Typically, in the optoelectronic device of the present invention, the second cation in the perovskite is a metal cation. The metal may be selected from tin, lead and copper, and is preferably selected from tin and lead.

[0076] More typically, the second cation is a divalent metal cation. For example, the second cation may be Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Sn 2+ , Yb 2+ and Eu 2+The second cation can be selected from Sn 2+ , Pb 2+ and Cu 2+ Typically, the second cation can be selected from Sn 2+ and Pb 2+ Choose from.

[0077] In the optoelectronic device of the present invention, the first cation in the perovskite is typically an organic cation.

[0078] The term "organic cation" refers to a cation that contains carbon. The cation can contain more elements, for example, the cation can contain hydrogen, nitrogen, or oxygen.

[0079] Typically, in the optoelectronic device of the present invention, the organic cation has the formula (R 1 R 2 R 3 R 4 N) + where R 1 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 2 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 3 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl, and R 4 is hydrogen, unsubstituted or substituted C 1 ~C 20 It is alkyl, or unsubstituted or substituted aryl.

[0080] Alternatively, the organic cation may be represented by the formula (R 5 NH 3 ) + where R5 is hydrogen or unsubstituted or substituted C 1 ~C 20 For example, R 5 can be methyl or ethyl. Typically, R 5 is methyl.

[0081] In some embodiments, the organic cation has the formula (R 5 R 6 N=CH-NR 7 R 8 ) + where R 5 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 6 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 7 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; and R 8 is hydrogen, unsubstituted or substituted C 1 ~C 20 It is alkyl, or unsubstituted or substituted aryl.

[0082] Typically, the cation (R 5 R 6 N=CH-NR 7 R 8 ) + R in 5 is hydrogen, methyl or ethyl; R 6 is hydrogen, methyl or ethyl; R 7 is hydrogen, methyl or ethyl, and R 8 is hydrogen, methyl or ethyl. For example, R 5 can be hydrogen or methyl; R 6 can be hydrogen or methyl; R 7 can be hydrogen or methyl, and R 8can be hydrogen or methyl.

[0083] Organic cations are, for example, those represented by the formula (H 2 N=CH-NH 2 ) + may have the following structure:

[0084] As used herein, an alkyl group can be a substituted or unsubstituted, straight-chain or branched-chain saturated radical, and is often a substituted or unsubstituted straight-chain saturated radical, more often an unsubstituted straight-chain saturated radical. 1 ~C 20 An alkyl group is an unsubstituted or substituted, straight or branched chain saturated hydrocarbon radical. Typically, an alkyl group is a C 1 ~C 10 Alkyl, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl, or C 1 ~C 6 Alkyl, for example, methyl, ethyl, propyl, butyl, pentyl or hexyl, or C 1 ~C 4 Alkyl is, for example, methyl, ethyl, i-propyl, n-propyl, t-butyl, s-butyl or n-butyl.

[0085] When the alkyl group is substituted, it is typically a substituted or unsubstituted C 1 ~C 20 Alkyl, substituted or unsubstituted aryl (as defined herein), cyano, amino, C 1 ~C 10 Alkylamino, di(C 1 ~C 10 ) Alkylamino, allylamino, diallylamino, allylalkylamino, amido, acylamide, hydroxy, oxo, halo, carboxy, ester, acyl, acyloxy, C 1 ~C 20 Alkoxy, aryloxy, haloalkyl, sulfonic acid, sulfhydryl (i.e., thiol, -SH), C 1 ~C 10The alkyl group contains one or more substituents selected from alkylthiol, arylthiol, sulfonyl, phosphoric acid, phosphoric acid ester, phosphonic acid, and phosphonic acid ester. Illustrative examples of substituted alkyl groups include haloalkyl, hydroxyalkyl, aminoalkyl, alkoxyalkyl, and alkaryl groups. The term alkaryl, as used herein, refers to a C alkyl group in which at least one hydrogen atom has been replaced with an aryl group. 1 ~C 20 It belongs to the alkyl group. Examples of such groups are benzyl (phenylmethyl, PhCH 2 -), benzhydryl (Ph 2 CH-), Trityl (triphenylmethyl, Ph 3 C-), phenethyl (phenylethyl, Ph-CH 2 CH 2 -), styryl (Ph-CH=CH-), cinnamyl (Ph-CH=CH-CH 2 -), but is not limited to:

[0086] Typically, a substituted alkyl group will bear 1, 2 or 3 substituents, for example 1 or 2.

[0087] An aryl group is a substituted or unsubstituted, typically monocyclic or bicyclic aromatic group containing from 6 to 14 carbon atoms, preferably from 6 to 10 carbon atoms, in the cyclic portion. Examples include phenyl, naphthyl, indenyl and indanyl groups. An aryl group is unsubstituted or substituted. When an aryl group as defined above is substituted, it is typically C 1 which is unsubstituted (to form an aralkyl group). 1 ~C 6 Alkyl, unsubstituted aryl, cyano, amino, C 1 ~C 10 Alkylamino, di(C 1 ~C 10 ) Alkylamino, arylamino, diallylamino, arylalkylamino, amido, acylamide, hydroxy, halo, carboxy, ester, acyl, acyloxy, C 1 ~C 20Alkoxy, aryloxy, haloalkyl, sulfhydryl (i.e., thiol, -SH), C 1 ~C 10 The aryl group contains one or more substituents selected from alkylthiol, allylthiol, sulfonic acid, phosphoric acid, phosphate ester, phosphonic acid and phosphonic acid ester, and sulfonyl. Typically, the aryl group carries 0, 1, 2 or 3 substituents. Substituted aryl groups are those that contain one C 1 ~C 6 An alkylene group or a group of the formula -X-(C 1 ~C 6 ) alkylene, or -X-(C 1 ~C 6 ) Two positions can be substituted with bidentate groups represented by alkylene-X-, where X is selected from O, S and NR, and R is H, aryl, or C. 1 ~C 6 It is alkyl. Thus, the substituted aryl group can be an aryl group fused with a cycloalkyl group or with a heterocyclyl group. The ring atoms of the aryl group can contain one or more heteroatoms (as in heteroaryl groups). Such aryl groups (heteroaryl groups) are substituted or unsubstituted monocyclic or bicyclic heteroaromatic groups that typically contain 6 to 10 atoms in the ring moiety containing one or more heteroatoms. It is generally a 5- or 6-membered ring containing at least one heteroatom selected from O, S, N, P, Se and Si. It can contain, for example, 1, 2 or 3 heteroatoms. Illustrative examples of heteroaryl groups include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, furanyl, thienyl, pyrazolidinyl, pyrrolyl, oxazolyl, oxadiazolyl, isoxazolyl, thiadiazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, quinolyl, and isoquinolyl. Heteroaryl groups can be unsubstituted or substituted, for example as specified above for aryl, and typically bear 0, 1, 2 or 3 substituents.

[0088] In the optoelectronic device of the present invention, R in the organic cation1 is hydrogen, methyl or ethyl; R 2 is hydrogen, methyl or ethyl; R 3 is hydrogen, methyl or ethyl, and R 4 is hydrogen, methyl or ethyl. For example, R 1 can be hydrogen or methyl; R 2 can be hydrogen or methyl; R 3 can be hydrogen or methyl, and R 4 can be hydrogen or methyl.

[0089] Alternatively, the organic cation may be represented by the formula (R 5 NH 3 ) + where R 5 is hydrogen or unsubstituted or substituted C 1 ~C 20 For example, R 5 can be methyl or ethyl. Typically, R 5 is methyl.

[0090] In one embodiment, the perovskite is a mixed-anion perovskite comprising two or more different anions selected from halide anions and chalcogenide anions, typically the two or more different anions are two or more different halide anions.

[0091] Thus, the perovskite utilized may be a mixed-anion perovskite comprising a first cation, a second cation, and two or more different anions selected from halide anions and chalcogenide anions. For example, the mixed-anion perovskite may comprise two different anions, e.g., the anions may be a halide anion and a chalcogenide anion, two different halide anions, or two different chalcogenide anions. The first and second cations may be as further defined hereinbefore. Thus, the first cation may be an organic cation, which may be further defined herein. For example, a perovskite having the formula (R 1 R 2 R 3 R 4 N) + or chemical formula (R 5 NH 3 ) + Alternatively, the organic cation can be a cation of the formula [R 5 R 6 N=CH-NR 7 R 8 ] + The second cation can be a divalent metal cation. For example, the second cation can be Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Typically, the second cation can be selected from Sn 2+ and Pb 2+ Choose from.

[0092] In the optoelectronic device of the present invention, the perovskite is usually a mixed halide perovskite, where the two or more different anions are two or more different halide anions. Typically, they are two or three halide anions, more typically two different halide anions. Usually, the halide anions are selected from fluoride, chloride, bromide and iodide, for example chloride, bromide and iodide.

[0093] Often, in the optoelectronic devices of the present invention, the perovskite has the chemical formula (I): [A][B][X] 3 (I) Here, [A] is at least one organic cation; [B] is at least one metal cation, and [X] is said at least one anion.

[0094] The perovskite of formula (I) can contain one, two, three or four different metal cations, typically one or two different metal cations. The perovskite of formula (I) can also contain, for example, one, two, three or four different organic cations, typically one or two different organic cations. Similarly, the perovskite of formula (I) can contain one, two, three or four different anions, typically two or three different anions.

[0095] The organic cations and metal cations in the perovskite compounds of formula (I) may be as further defined hereinbefore. Thus, the organic cations may be selected from the group consisting of perovskite compounds of formula (R 1 R 2 R 3 R 4 N) + The cation and chemical formula (R 5 NH 3 ) +The metal cation can be selected from divalent metal cations. For example, the metal cation can be selected from Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Typically, the metal cation is selected from Sn 2+ or Pb 2+ It is.

[0096] The organic cation may be, for example, a compound having the formula (R 5 R 6 N=CH-NR 7 R 8 ) + and the chemical formula (H 2 N=CH-NH 2 ) + The metal cation can be selected from divalent metal cations. For example, the metal cation can be selected from Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Typically, the metal cation is selected from Sn 2+ or Pb 2+ It is.

[0097] Typically, [X] in formula (I) is two or more different anions selected from a halide anion and a chalcogenide anion. More typically, [X] is two or more different halide anions.

[0098] In one embodiment, the perovskite has the formula (IA): AB[X] 3 (IA) Here, A is an organic cation; B is a metal cation, and [X] are two or more different halide anions.

[0099] Typically, [X] in formula (IA) is two or more different anions selected from halide anions and chalcogenide anions. Usually, [X] is two or more different halide anions. Preferably, [X] is two or three different halide anions. More preferably, [X] is two different halide anions. In another embodiment, [X] is three different halide anions.

[0100] The organic cations and metal cations in the perovskite compounds of formula (IA) may be as further defined hereinbefore. Thus, the organic cations may be selected from the group consisting of perovskite compounds of formula (R 1 R 2 R 3 R 4 N) + The cation and chemical formula (R 5 NH 3 ) + The metal cation can be a divalent metal cation. For example, the metal cation can be selected from Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+, Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Typically, the metal cation is selected from Sn 2+ or Pb 2+ It is.

[0101] The organic cation may be, for example, a compound having the formula (R 5 R 6 N=CH-NR 7 R 8 ) + and the chemical formula (H 2 N=CH-NH 2 ) + The metal cation can be a divalent metal cation. For example, the metal cation can be selected from Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Typically, the metal cation is selected from Sn 2+ or Pb 2+ It is.

[0102] Typically, in the optoelectronic device of the present invention, the perovskite has the chemical formula (II): ABX 3-y X' y (II) Here, A is an organic cation; B is a metal cation; X is a first halide anion; X' is a second halide anion different from the first halide anion, and y ranges from 0.05 to 2.95.

[0103] Usually, y is from 0.5 to 2.5, for example from 0.75 to 2.25. Typically, y is from 1 to 2.

[0104] Again, in formula (II), the organic cation and the metal cation can be as further defined hereinbefore. Thus, the organic cation can be a compound of formula (R 1 R 2 R 3 R 4 N) + or, more typically, a cation of the formula (R 5 NH 3 ) + The metal cation can be a divalent metal cation. For example, the metal cation can be Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Typically, the metal cation is selected from Sn 2+ or Pb 2+ It is.

[0105] In some embodiments, the perovskite has formula (IIa): ABX 3z X' 3(1-z) (IIa) Here, A is a compound represented by the chemical formula (R 5 R 6 N=CH-NR 7 R 8 ) + where R 5is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 6 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 7 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; and R 8 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; B is a metal cation; X is a first halide anion; X' is a second halide anion different from the first halide anion, and z is greater than 0 and less than 1. Typically, z is between 0.05 and 0.95.

[0106] Typically, z is from 0.1 to 0.9. z can be, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9, and z can range from any one of these values ​​to any other of these values ​​(e.g., from 0.2 to 0.7, or from 0.1 to 0.8).

[0107] B, X and X' can be as previously defined herein. The organic cation can be, for example, (R 5 R 6 N=CH-NR 7 R 8 ) + where R 5 , R 6 , R 7 and R 8 is hydrogen and unsubstituted or substituted C 1 ~C 6 For example, the organic cation may be selected from the group consisting of (H2 N=CH-NH 2 ) + It can be said that:

[0108] In many cases, in the optoelectronic devices of the present invention, the perovskite is CH 3 NH 3 PbI 3 , C.H. 3 NH 3 PbBr 3 , C.H. 3 NH 3 PbCl 3 , C.H. 3 NH 3 PbF 3 , C.H. 3 NH 3 PbBrI 2 , C.H. 3 NH 3 PbBrCl 2 , C.H. 3 NH 3 PbIBr 2 , C.H. 3 NH 3 PbICl 2 , C.H. 3 NH 3 PbClBr 2 , C.H. 3 NH 3 PbI 2 Cl, CH 3 NH 3 SnBrI 2 , C.H. 3 NH 3 SnBrCl 2 , C.H. 3 NH 3 SnF 2 Br, C.H. 3 NH 3 SnIBr 2 , C.H. 3 NH 3 SnICl 2 , C.H. 3 NH 3 SnF 2 I, C.H. 3 NH 3 SnClBr 2 , C.H. 3 NH 3 SnI 2Cl and CH 3 NH 3 SnF 2 Cl is a perovskite compound.

[0109] For example, in the optoelectronic device of the present invention, the perovskite is 3 NH 3 PbBrI 2 , C.H. 3 NH 3 PbBrCl 2 , C.H. 3 NH 3 PbIBr 2 , C.H. 3 NH 3 PbICl 2 , C.H. 3 NH 3 PbClBr 2 , C.H. 3 NH 3 PbI 2 Cl, CH 3 NH 3 SnBrI 2 , C.H. 3 NH 3 SnBrCl 2 , C.H. 3 NH 3 SnF 2 Br, C.H. 3 NH 3 SnIBr 2 , C.H. 3 NH 3 SnICl 2 , C.H. 3 NH 3 SnF 2 I, C.H. 3 NH 3 SnClBr 2 , C.H. 3 NH 3 SnI 2 Cl and CH 3 NH 3 SnF 2 Cl.

[0110] Typically, perovskites are 3 NH 3 PbBrI 2 , C.H.3 NH 3 PbBrCl 2 , C.H. 3 NH 3 PbIBr 2 , C.H. 3 NH 3 PbICl 2 , C.H. 3 NH 3 PbClBr 2 , C.H. 3 NH 3 PbI 2 Cl, CH 3 NH 3 SnF 2 Br, C.H. 3 NH 3 SnICl 2 , C.H. 3 NH 3 SnF 2 I, C.H. 3 NH 3 SnI 2 Cl and CH 3 NH 3 SnF 2 Select from Cl.

[0111] More typically, the perovskite is 3 NH 3 PbBrI 2 , C.H. 3 NH 3 PbBrCl 2 , C.H. 3 NH 3 PbIBr 2 , C.H. 3 NH 3 PbICl 2 , C.H. 3 NH 3 PbClBr 2 , C.H. 3 NH 3 PbI 2 Cl, CH 3 NH 3 SnF 2 Br, C.H. 3 NH 3 SnF 2 I and CH 3 NH 3 SnF 2 Select from Cl.

[0112] Usually, perovskites are 3 NH 3 PbBrI 2 , C.H. 3 NH 3 PbBrCl 2 , C.H. 3 NH 3 PbIBr 2 , C.H. 3 NH 3 PbICl 2 , C.H. 3 NH 3 SnF 2 Br and CH 3 NH 3 SnF 2 Choose from I.

[0113] In most cases, the perovskite used is CH 3 NH 3 PbCl 2 I.

[0114] In some embodiments, the perovskite is represented by the formula (H 2 N=CH-NH 2 )PbI 3z Br 3(1-z) where z is greater than 0 and less than 1. z may be as further defined herein above.

[0115] The perovskite semiconductors utilized in the optoelectronic devices of the present invention may comprise, for example, a mixture of the mixed-anion perovskite and the single-anion perovskite, where the single-anion perovskite comprises a first cation, a second cation, and an anion selected from a halide anion and a chalcogenide anion, where the first cation and the second cation are as defined herein for the mixed-anion perovskite. 3 NH 3 PbICl 2 and C.H. 3 NH 3PbI 3 ;CH 3 NH 3 PbICl 2 and C.H. 3 NH 3 PbBr 3 ;CH 3 NH 3 PbBrCl 2 and C.H. 3 NH 3 PbI 3 ; or CH 3 NH 3 PbBrCl 2 and C.H. 3 NH 3 PbBr 3 may include.

[0116] Photoelectron devices are made up of a compound represented by the chemical formula (H 2 N=CH-NH 2 )PbI 3z Br 3(1-z) where z is as defined herein and (H 2 N=CH-NH 2 )PbI 3 Or (H 2 N=CH-NH 2 )PbBr 3 and other single anion perovskites.

[0117] Alternatively, the perovskite semiconductor utilized in the optoelectronic device of the present invention may comprise more than one perovskite, where each perovskite is a mixed-anion perovskite, where the mixed-anion perovskite is as defined herein. For example, the optoelectronic device may comprise two or three of the perovskites. The optoelectronic device of the present invention may, for example, comprise two perovskites, where both perovskites are mixed-anion perovskites. For example, the optoelectronic device may comprise a CH 3 NH 3 PbICl 2 and C.H. 3 NH 3 PbIBr 2 ;CH3 NH 3 PbICl 2 and C.H. 3 NH 3 PbBrI 2 ;CH 3 NH 3 PbBrCl 2 and C.H. 3 NH 3 PbIBr 2 ; or CH 3 NH 3 PbBrCl 2 and C.H. 3 NH 3 PbIBr 2 may include.

[0118] The optoelectronic device may include two different perovskites, where each perovskite has the chemical formula (H 2 N=CH-NH 2 )PbI 3z Br 3(1-z) where z is as defined herein.

[0119] In some embodiments of the optoelectronic device of the present invention, [B] is Pb 2+ When [B] is a single metal cation, one of the two or more different halide anions is iodide or fluoride, and [B] is Sn 2+When the single metal cation is, one of the two or more different halide anions is fluoride. Typically, in some embodiments of the optoelectronic device of the present invention, one of the two or more different halide anions is iodide or fluoride. Typically, in some embodiments of the optoelectronic device of the present invention, one of the two or more different halide anions is iodide and another of the two or more different halide anions is fluoride or chloride. Often, in some embodiments of the optoelectronic device of the present invention, one of the two or more different halide anions is fluoride. Typically, in some embodiments of the optoelectronic device of the present invention, either (a) one of the two or more different anions is fluoride and another of the two or more different anions is chloride, bromide or iodide, or (b) one of the two or more different anions is iodide and another of the two or more different anions is fluoride or chloride. Typically, [X] is two different halide anions, X and X'. In many cases, in the optoelectronic device of the present invention, the divalent metal cation is Sn 2+ Alternatively, in the optoelectronic device of the present invention, the divalent metal cation is Pb 2+ It can be said that:

[0120] The n-type region in the optoelectronic device of the present invention comprises one or more n-type layers. In many cases, the n-type region is an n-type layer, i.e., a single n-type layer. In another embodiment, however, the n-type region can comprise an n-type layer and an n-type exciton blocking layer. In the case where an n-type exciton blocking layer is utilized, the n-type exciton blocking layer is typically disposed between the n-type layer and the layer comprising the perovskite semiconductor.

[0121] The exciton blocking layer is a material with a wider band gap than the perovskite, but has either a conduction band or a valence band that closely matches the conduction band or the valence band of the perovskite. If the conduction band (or the lowest unoccupied molecular orbital energy level) of the exciton blocking layer closely aligns with the conduction band of the perovskite, electrons will travel from the perovskite into the exciton blocking layer and through the exciton blocking layer, or through the exciton blocking layer to the perovskite, and we call this an n-type exciton blocking layer. An example of such is bathocuproine, as described in {P. Peumans, A. Yakimov, and S. R. Forrest, "Small molecular weight organic thin-film photodetectors and solar cells" J. Appl. Phys. 93, 3693 (2001)} and {Masaya Hirade, and Chihaya Adachi, "Small molecular organic photovoltaic cells with exciton blocking layer at anode interface for improved device performance" Appl. Phys. Lett. 99, 153302 (2011)}.

[0122] An n-type layer is a layer of electron-transporting (i.e., n-type) material. The n-type material can be a single n-type compound or elemental material, or a mixture of two or more n-type compound or elemental materials, which may be undoped or doped with one or more dopant elements.

[0123] The n-type layers utilized in the optoelectronic devices of the present invention may comprise inorganic or organic n-type materials.

[0124] Suitable inorganic n-type materials may be selected from metal oxides, metal sulfides, metal selenides, metal tellurides, perovskites, amorphous Si, n-type Group IV semiconductors, n-type Group III-V semiconductors, n-type Group II-VI semiconductors, n-type Group I-VII semiconductors, n-type Group IV-VI semiconductors, n-type Group V-VI semiconductors, and n-type Group II-V semiconductors, any of which may be doped or undoped.

[0125] The n-type material may be selected from metal oxides, metal sulfides, metal selenides, metal tellurides, amorphous Si, n-type Group IV semiconductors, n-type Group III-V semiconductors, n-type Group II-VI semiconductors, n-type Group I-VII semiconductors, n-type Group IV-VI semiconductors, n-type Group V-VI semiconductors, and n-type Group II-V semiconductors, any of which may be doped or undoped.

[0126] More typically, the n-type material is selected from metal oxides, metal sulfides, metal selenides, and metal tellurides.

[0127] Thus, the n-type layer may comprise an inorganic material selected from an oxide of titanium, tin, zinc, niobium, tantalum, tungsten, indium, gallium, neodymium, palladium, or cadmium, or a mixture of two or more of the above metals. 2 , SnO 2 , ZnO, Nb 2 O 5 , Ta 2 O 5 , WO 3 , W 2 O 5 , In 2 O 3 , Ga 2 O 3 , Nd 2 O 3 , PbO, or CdO.

[0128] Other suitable n-type materials that can be utilized include sulfides of cadmium, tin, copper, or zinc, including sulfides of mixtures of two or more of the above metals. For example, the sulfide may be FeS2 , CdS, ZnS or Cu 2 ZnSnS 4 It can be said that:

[0129] The n-type layer may, for example, comprise a selenide of cadmium, zinc, indium, or gallium, or a mixture of two or more of the above metals; or a telluride of cadmium, zinc, cadmium, or tin, or a mixture of two or more of the above metals. For example, the selenide may be Cu(In,Ga)Se 2 Typically, the telluride is a telluride of cadmium, zinc, cadmium or tin. For example, the telluride can be CdTe.

[0130] The n-type layer may comprise an inorganic material selected from, for example, oxides of titanium, tin, zinc, niobium, tantalum, tungsten, indium, gallium, neodymium, palladium, cadmium, or oxides of a mixture of two or more of the above metals; sulfides of cadmium, tin, copper, zinc, or sulfides of a mixture of two or more of the above metals; selenides of cadmium, zinc, indium, gallium, or selenides of a mixture of two or more of the above metals; or tellurides of cadmium, zinc, cadmium, or tin, or tellurides of a mixture of two or more of the above metals.

[0131] Examples of other semiconductors that may be suitable n-type materials include, for example, Group IV compound semiconductors, amorphous Si, Group III-V semiconductors (e.g., gallium arsenide), Group II-VI semiconductors (e.g., cadmium selenide), Group I-VII semiconductors (e.g., cuprous chloride), Group IV-VI semiconductors (e.g., lead selenide), Group V-VI semiconductors (e.g., bismuth telluride), and Group II-V semiconductors (e.g., cadmium arsenide), when they are n-doped.

[0132] Typically, the n-type layer is TiO 2 Includes.

[0133] The n-type layer is made of an inorganic material, such as TiO2 or any of the other materials listed above, the n-type layer can be a dense layer of said inorganic material. Preferably, the n-type layer is TiO 2 It is a dense layer.

[0134] Other n-type materials, including organic and polymeric electron transport materials and electrolytes, can also be used. Suitable examples include, but are not limited to, organic electron transport materials including fullerene or fullerene derivatives, perylene or its derivatives, or poly{[N,N0-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,50-(2,20-bithiophene)} (P(NDI2OD-T2)).

[0135] The p-type region in the optoelectronic device of the present invention comprises one or more p-type layers. In many cases, the p-type region is a p-type layer, i.e., a single p-type layer. In another embodiment, however, the p-type region can comprise a p-type layer and a p-type exciton blocking layer. In the case where a p-type exciton blocking layer is utilized, the p-type exciton blocking layer is typically disposed between the p-type layer and the layer comprising the perovskite semiconductor. If the valence band (or highest occupied molecular orbital level) of the exciton blocking layer is closely aligned with the valence band of the perovskite, holes can pass from the perovskite into the exciton blocking layer and through the exciton blocking layer, or pass through the exciton blocking layer to the perovskite, which we term a p-type exciton blocking layer. An example of such a compound is tris[4-(5-phenylthiophen-2-yl)phenyl]amine, as described in {Masaya Hirade, and Chihaya Adachi, "Small molecular organic photovoltaic cells with exciton blocking layer at anode interface for improved device performance" Appl. Phys. Lett. 99, 153302 (2011)}.

[0136] A p-type layer is a layer of hole-transporting (i.e., p-type) material. The p-type material can be a single p-type compound or elemental material, or a mixture of two or more p-type compounds or elemental materials, which may be undoped or doped with one or more dopant elements.

[0137] The p-type layers utilized in the optoelectronic devices of the present invention may comprise inorganic or organic p-type materials.

[0138] Suitable p-type materials can be selected from polymeric or molecular hole transporters. The p-type layer utilized in the optoelectronic devices of the present invention can include, for example, spiro-OMeTAD (2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)9,9'-spirobifluorene)), P3HT (poly(3-hexylthiophene)), PCPDTBT (poly[2,1,3-benzothiadiazole-4,7-diyl[4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene-2,6-diyl]]), PVK (poly(N-vinylcarbazole)), HTM-TFSI (1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide), Li-TFSI (lithium bis(trifluoromethanesulfonyl)imide), or tBP (tertiary butylpyridine). Typically, the p-type material is selected from spiro-OMeTAD, P3HT, PCPDTBT and PVK. Preferably, the p-type layer utilized in the optoelectronic device of the present invention comprises spiro-OMeTAD.

[0139] The p-type layer can include, for example, spiro-OMeTAD (2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)9,9'-spirobifluorene)), P3HT (poly(3-hexylthiophene)), PCPDTBT (poly[2,1,3-benzothiadiazole-4,7-diyl[4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene-2,6-diyl]]), or PVK (poly(N-vinylcarbazole)).

[0140] Suitable p-type materials also include molecular hole transporters, polymeric hole transporters, and copolymeric hole transporters. The p-type material can be, for example, a molecular hole transport material, a polymer or copolymer that includes one or more of the following moieties: thiophenyl, phenelenyl, dithiazolyl, benzothiazolyl, diketopyrrolopyrrolyl, ethoxydithiophenyl, amino, triphenylamino, carbozolyl, ethylenedioxyphenyl, dioxythiophenyl, or fluorenyl. Thus, the p-type layer utilized in the optoelectronic device of the present invention can include, for example, any of the molecular hole transport materials, polymers, or copolymers described above.

[0141] Suitable p-type materials include m-MTDATA (4,4',4''-tris(methylphenylphenylamino)triphenylamine), MeOTPD (N,N,N',N'-tetrakis(4-methoxyphenyl)-benzidine), BP2T (5,5'-di(biphenyl-4-yl)-2,2'-bithiophene), di-NPB (N,N'-di-[(1-naphthyl)-N,N'-diphenyl]-1,1'-biphenyl)-4,4'-diamine), α-NPB (N,N'-di(naphthalen-1-yl)-N,N'-diphenyl-benzidine), TNA Also included are TA (4,4',4''-tris-(N-(naphthylene-2-yl)-N-phenylamine)triphenylamine), BPAPF (9,9-bis[4-(N,N-bis-biphenyl-4-yl-amino)phenyl]-9H-fluorene), spiro-NPB (N2,N7-di-1-naphthalenyl-N2,N7-diphenyl-9,9'-spirobi[9H-fluorene]-2,7-diamine), 4P-TPD (4,4'-bis-(N,N-diphenylamino)-tetraphenyl), PEDOT:PSS and spiro-OMeTAD.

[0142] The p-type layer can be doped with an ionic salt or base. The p-type layer can be doped with an ionic salt selected from HMI-TFSI (1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) and Li-TFSI (lithium bis(trifluoromethanesulfonyl)imide), or with a base, which is tBP (tertiary butylpyridine).

[0143] Additionally or alternatively, the p-type layer can be doped to increase the hole concentration. 4 (nitrosonium tetrafluoroborate).

[0144] In another embodiment, the p-type layer can include an inorganic hole transporter. For example, the p-type layer can include an oxide of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu 2 The p-type layer may comprise an inorganic hole transporter including: O, CuO or CIS; perovskite; amorphous Si; p-type IV semiconductors, p-type III-V semiconductors, p-type II-VI semiconductors, p-type I-VII semiconductors, p-type IV-VI semiconductors, p-type V-VI semiconductors, and p-type II-V semiconductors, which may be doped or undoped. The p-type layer may be a dense layer of the inorganic hole transporter.

[0145] The p-type layer may be, for example, an oxide of nickel, vanadium, copper or molybdenum; CuI, CuBr, CuSCN, Cu 2 The p-type layer may comprise inorganic hole transporters including p-type Group IV semiconductors, p-type Group III-V semiconductors, p-type Group II-VI semiconductors, p-type Group I-VII semiconductors, p-type Group IV-VI semiconductors, p-type Group V-VI semiconductors, and p-type Group II-V semiconductors, which may be doped or undoped. The p-type layer may comprise, for example, CuI, CuBr, CuSCN, Cu 2The p-type layer may comprise an inorganic hole transporter selected from O, CuO or CIS. The p-type layer may be a dense layer of the inorganic hole transporter.

[0146] Typically, the p-type layer comprises a polymeric or molecular hole transporter and the n-type layer comprises an inorganic n-type material. The p-type polymeric or molecular hole transporter can be any suitable polymeric or molecular hole transporter, such as any of those listed above. Similarly, the inorganic n-type material can be any suitable n-type inorganic, such as any of those listed above. In one embodiment, for example, the p-type layer comprises spiro-OMeTAD and the n-type layer comprises TiO 2 Typically, the embodiment includes TiO 2 The n-type layer containing TiO 2 It is a dense layer.

[0147] In another embodiment, both the n-type layer and the p-type layer comprise an inorganic material. Thus, the n-type layer can comprise an inorganic n-type material and the p-type layer can comprise an inorganic p-type material. The inorganic p-type material can be any suitable p-type inorganic material, such as any of those listed above. Similarly, the inorganic n-type material can be any suitable n-type inorganic material, such as any of those listed above.

[0148] In yet another embodiment, the p-type layer comprises an inorganic p-type material (i.e., an inorganic hole transporter) and the n-type layer comprises a polymeric or molecular hole transporter. The inorganic p-type material can be any suitable p-type inorganic, such as any of those listed above. Similarly, the n-type polymeric or molecular hole transporter can be any suitable n-type polymeric or molecular hole transporter, such as any of those listed above.

[0149] For example, the p-type layer can include an inorganic hole transporter and the n-type layer can include an electron transport material, where the electron transport material includes a fullerene or a fullerene derivative, an electrolyte, or an organic electron transport material, preferably the organic electron transport material includes perylene or a derivative thereof, or poly{[N,N0-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,50-(2,20-bithiophene)} (P(NDI2OD-T2)). The inorganic hole transporter can be, for example, an oxide of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu 2 O, CuO or CIS; perovskite; amorphous Si; p-type Group IV semiconductors, p-type Group III-V semiconductors, p-type Group II-VI semiconductors, p-type Group I-VII semiconductors, p-type Group IV-VI semiconductors, p-type Group V-VI semiconductors, and p-type Group II-V semiconductors, which may be doped or undoped. More typically, inorganic hole transporters are oxides of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu 2 , CuO, CuO, or CIS; p-type Group IV semiconductors, p-type Group III-V semiconductors, p-type Group II-VI semiconductors, p-type Group I-VII semiconductors, p-type Group IV-VI semiconductors, p-type Group V-VI semiconductors, and p-type Group II-V semiconductors, which may be doped or undoped. Thus, inorganic hole transporters include oxides of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu 2 It may contain O, CuO or CIS.

[0150] The following paragraphs relate to the use of a second, p-type perovskite in the p-type layer, or a second, n-type perovskite in the n-type layer. (In preferred embodiments, however, neither the p-type nor the n-type layers contain a perovskite. Thus, preferably, neither the p-type nor the n-type regions contain a perovskite.)

[0151] When a p-type layer includes an inorganic hole transporter that is a perovskite, the perovskite is different from the perovskite used in the layer of perovskite semiconductor without open pores and in the "first layer" that also includes a scaffold material, when present. Thus, when a p-type layer includes an inorganic hole transporter that is a perovskite, the perovskite of the p-type layer is termed herein the "second perovskite" (and the perovskite in the layer of perovskite semiconductor without open pores and in the first layer, when present, is referred to herein as the "first perovskite").

[0152] Similarly, when an n-type layer includes an inorganic electron transporter that is a perovskite, the perovskite will be different from the perovskite used in the layer of perovskite semiconductor without open pores and in the "first layer" that also includes a scaffold material, when present. Thus, when an n-type layer includes an inorganic electron transporter that is a perovskite, the perovskite is termed herein the "second perovskite" (and the perovskite in the layer of perovskite semiconductor without open pores and in the first layer, when present, is referred to herein as the "first perovskite").

[0153] Those skilled in the art will recognize that the addition of doping agents to a perovskite can be used to control the charge transport properties of the perovskite. Thus, for example, an intrinsic perovskite can be doped to form an n-type material or a p-type material. Thus, the first perovskite and / or the second perovskite can include one or more doping agents. Typically, the doping agents are dopant elements.

[0154] The addition of different doping agents to different samples of the same material can result in the different samples having different charge transport properties. For example, the addition of one doping agent to a first sample of a perovskite material can result in the first sample being an n-type material, while the addition of a different doping agent to a second sample of the same perovskite material can result in the second sample being a p-type material.

[0155] Thus, at least one of the first and second perovskite may include a doping agent. The first perovskite may, for example, include a doping agent that is not present in the second perovskite or in each of the second perovskites. Additionally or alternatively, the second perovskite or one of the second perovskites may include a doping agent that is not present in the first perovskite. Thus, the difference between the first and second perovskite may be the presence or absence of a doping agent, or the use of a different doping agent in each perovskite. Alternatively, the difference between the first and second perovskite may not be in the doping agent, but instead, the difference may be in the overall structure of the first and second perovskite.

[0156] When present, the second perovskite may be a perovskite that includes a first cation, a second cation, and at least one anion.

[0157] In some embodiments, the second perovskite utilized in the p-type or n-type layer and different from the first perovskite has the formula (IB): [A][B][X] 3 (IB) Here, [A] is at least one organic cation or at least one Group I metal cation; [B] is at least one metal cation, and [X] is at least one anion.

[0158] As one skilled in the art would recognize, [A] is Cs + may include.

[0159] Usually, [B] is Pb 2+ Or Sn 2+ More typically, [B] is Pb 2+ Includes.

[0160] Typically, [X] comprises a halide anion or a number of different halide anions.

[0161] Usually, [X] is I - Includes.

[0162] In some embodiments, [X] is two or more different anions, such as two or more different halide anions. For example, [X] is I - and F - , I - and Br - , or I - and Cl - may include.

[0163] Typically, the perovskite compound of formula IB is CsPbI 3 or CsSnI 3 For example, the perovskite compound of formula (IB) is 3 It can be said that:

[0164] Alternatively, the perovskite compound of formula (IB) may be prepared by adding CsPbI 2 Cl, CsPbICl 2 , CsPbI 2 F, CsPbIF 2 , CsPbI 2 Br, CsPbIBr 2 , CsSnI 2 Cl, CsSnICl 2 , CsSnI 2 F, CsSnIF 2, CsSnI 2 Br or CsSnIBr 2 For example, the perovskite compound of formula (IB) can be prepared by adding CsPbI 2 Cl or CsPbICl 2 Typically, the perovskite compound of formula (IB) is CsPbICl 2 It is.

[0165] In the perovskite compound of formula (IB): [X] can be one or more different anions as defined herein, for example two or more different anions as defined herein for the first perovskite; [A] typically comprises an organic cation as defined herein above for the first perovskite; and [B] typically comprises a metal cation as defined herein. The metal cation can be defined as hereinbefore for the first perovskite.

[0166] In some embodiments, the second perovskite is a perovskite as defined herein above for the first perovskite, allowing the second perovskite to be different from the first perovskite.

[0167] The scaffold material utilized in embodiments of the optoelectronic device of the present invention including the first layer may be a dielectric scaffold material, typically having a band gap of 4.0 eV or greater.

[0168] Typically, in optoelectronic devices of the invention, the dielectric scaffold material comprises an oxide of aluminum, zircon, silicon, yttrium, or ytterbium. For example, the dielectric scaffold material may comprise zirconium oxide, silica, alumina, ytterbium oxide or yttrium oxide, or alumina silicate. Often, the dielectric scaffold material comprises silica or alumina. More typically, the dielectric scaffold material comprises porous alumina.

[0169] Typically, in optoelectronic devices of the invention, the dielectric scaffold material is mesoporous. Thus, typically, in optoelectronic devices of the invention, the dielectric scaffold material comprises mesoporous alumina.

[0170] Alternatively, the scaffold material can be an inorganic electron transport material, such as, for example, titania. Thus, for example, the scaffold material can include oxides of titanium, tin, zinc, niobium, tantalum, tungsten, indium, gallium, neodymium, palladium, or cadmium. For example, the scaffold material can be TiO 2 , SnO 2 , ZnO, Nb 2 O 5 , Ta 2 O 5 , WO 3 , W 2 O 5 , In 2 O 3 , Ga 2 O 3 , Nd 2 O 3 , PbO, or CdO. Often the scaffolding material can comprise a mesoporous oxide of titanium, tin, zinc, niobium, tantalum, tungsten, indium, gallium, neodymium, palladium, or cadmium, or mixtures thereof. Titania, porous titania, and mesoporous titania are preferred. Typically in such embodiments the scaffolding material comprises porous titania, preferably mesoporous titania.

[0171] The scaffold material can include, for example, an inorganic hole transport material.

[0172] The scaffold material, on the other hand, can be an inorganic hole transport material. Thus, the scaffold material can be, for example, an oxide of nickel, vanadium, copper or molybdenum, CuI, CuBr, CuSCN, Cu 2It may contain O, CuO or CIS.

[0173] The porosity of the scaffold material utilized in the embodiment of the optoelectronic device of the present invention comprising the first layer is typically 50% or more. For example, the porosity may be about 70%. In one embodiment, the porosity is 60% or more, for example 70% or more.

[0174] Typically, in the optoelectronic device of the present invention, the thickness of the photoactive region is from 100 nm to 3000 nm, for example from 200 nm to 1000 nm, or for example, the thickness can be from 300 nm to 800 nm. In many cases, the thickness of the photoactive layer is from 400 nm to 600 nm. Usually, the thickness is about 500 nm.

[0175] The optoelectronic device of the present invention generally comprises a first electrode and a second electrode. Thus, the optoelectronic device of the present invention typically comprises a first electrode, a second electrode, and the photoactive region disposed between the first electrode and the second electrode.

[0176] The first electrode and the second electrode are the anode and the cathode, and usually, one or both of the anode and the cathode are transparent to allow the entry of light. At least one of the electrodes is usually translucent over the visible region to the near-infrared region of the solar spectrum. Translucency typically has a transparency of 80%, and ranges from 40% to 90%. The selection of the first electrode and the second electrode of the optoelectronic device of the present invention may depend on the type of structure. Typically, the first layer of the device is deposited onto the first electrode containing tin oxide, and more typically, onto a fluorine-doped tin oxide (FTO) anode, which is usually a transparent or translucent material. Thus, the first electrode is usually transparent and typically contains tin oxide, more typically fluorine-doped tin oxide (FTO). Usually, the thickness of the first electrode ranges from 200 nm to 600 nm, and more typically from 300 nm to 500 nm. For example, the thickness can be 400 nm. Typically, FTO is coated onto a glass sheet. Usually, the second electrode contains a metal with a large work function, such as gold, silver, nickel, palladium, or platinum, typically silver. Usually, the thickness of the second electrode ranges from 50 nm to 250 nm, and more generally from 100 nm to 200 nm. For example, the thickness of the second electrode can be 150 nm.

[0177] In many cases, the first electrode will include a transparent or semi-transparent electrically conductive material. For example, the first electrode can include a transparent conductive oxide. Transparent conductive oxides include tin oxide, zinc oxide, doped tin oxide, and doped zinc oxide. For example, the first electrode can include ITO (indium tin oxide), FTO (fluorine-doped tin oxide), or AZO (aluminum-doped tin oxide), preferably FTO. The first electrode can include 90 to 100% by weight of ITO, FTO, or AZO, and in some cases, the first electrode can consist essentially of ITO, FTO, or AZO. Typically, the thickness of the first electrode is 200 nm to 600 nm, more typically 300 nm to 500 nm. For example, the thickness can be 400 nm. The first electrode will often be disposed on a glass substrate. For example, the first electrode can include FTO and can be disposed on a glass substrate. In the optoelectronic device of the present invention, the first electrode is often transparent or semi-transparent, so that the light ingress and / or egress typically occurs through the first electrode. Light can enter the device through the metal electrode (as the second electrode often can) especially when the metal electrode forms a thin layer.

[0178] In many cases, the second electrode comprises a metal. Typically, the second electrode comprises a high work function metal, such as aluminum, gold, silver, nickel, palladium or platinum, typically silver or gold. Typically, the second electrode has a thickness of 50 nm to 250 nm, more typically 100 nm to 200 nm. For example, the second electrode may have a thickness of 150 nm.

[0179] In one embodiment of the present invention, the optoelectronic device of the present invention may include a first electrode, a second electrode, and the photoactive region disposed between the first electrode and the second electrode, where the first electrode contacts an n-type region of the photoactive region and the second electrode contacts a p-type region of the photoactive region.

[0180] Thus, an optoelectronic device according to the invention may comprise the following regions in the following order: I. a first electrode; II. An n-type region comprising at least one n-type layer; III. A layer of a perovskite semiconductor without open pores; IV. A p-type region comprising at least one p-type layer; and V. Second electrode.

[0181] The term "the following regions in the following order" as used herein means that each of the listed regions will be present and that the order of each of the layers shown will be in the order given. For example, in the above case (I, II, III, IV, V), II follows I and precedes III, and II alone is between I and III (i.e., neither IV nor V is between I and III, only II). This is the normal understanding of "in the following order". The order, however, does not define the orientation in space of the collection of regions: I, II, III is equivalent to III, II, I (i.e., does not define "top" and "bottom" or "left" and "right"). Additional layers or regions can be shown between each of these regions. For example, I, II, III includes I, Ia, II, IIa, III and I, Ia, Ib, II, III. Typically, in any way, each region (e.g., I to V) contacts both the preceding region and the following region.

[0182] Additional layers or regions may be present between each of these regions. Typically, each region I to V is in contact with both the preceding and succeeding regions in any way. Each of the regions (first electrode, n-type region, layer of perovskite semiconductor without open pores, p-type region and second electrode) may be as defined anywhere herein. For example, an optoelectronic device according to the invention may comprise the following regions in the following order: I. A first electrode comprising a transparent conductive oxide, preferably FTO; II. An n-type region comprising at least one n-type layer; III. A layer of a perovskite semiconductor without open pores; IV. A p-type region comprising at least one p-type layer; and V. A second electrode comprising a metal, preferably silver or gold.

[0183] In some embodiments, the second electrode can instead comprise a transparent conductive oxide. For example, both the first electrode and the second electrode can be selected from ITO, FTO and AZO. When the second electrode comprises a metal such as silver or gold, the thickness of the second electrode can sometimes be from 1 nm to 10 nm. For example, the first electrode can comprise FTO or ITO, and the second electrode can comprise a layer of silver having a thickness of from 1 nm to 10 nm, for example, from 5 nm to 10 nm. The thin layer of silver can be semi-transparent.

[0184] The present invention also provides an inverted heterojunction thin film perovskite device. Thus, in one embodiment, the optoelectronic device of the present invention may include a first electrode, a second electrode, and the photoactive region disposed between the first and second electrodes, where the second electrode contacts an n-type region of the photoactive region and the first electrode contacts a p-type region of the photoactive region. Such architectures lead to what are known as inverted devices. These devices may have the configuration shown diagrammatically in FIG. 8. In some circumstances, it is desirable to have an inverted device structure in which holes are collected through the substrate side of the device. In particular, inverted device architectures may be required for tandem applications. Tandem applications include use with a number of inorganic photovoltaic low band gap cells such as CIGS. The inventors have developed low temperature, ambient air, solution processable photovoltaic cells based on semiconducting perovskite absorbers. In many cases, selective p-type and n-type contacts are formed from PEDOT:PSS and PC, respectively. 60Remarkably, even though the photoactive layer where the bulk heterojunction is replaced by a solid perovskite film, the final electrode configuration is very similar to that utilized in "bulk heterojunction" polymer solar cells, achieving a very satisfactory 7.5% total solar power conversion efficiency with considerable room for further improvement.

[0185] Thin-film photovoltaics based on solution-processable technologies offer the bright promise of low-cost, easily manufacturable devices needed to meet the world's ever-increasing energy demands. Suitable candidates are organic-based photovoltaics, inorganic and hybrid structures. Organic-based photovoltaics, while providing a low-cost, easily processable technology, suffer from reduced performance compared to other thin-film technologies due to fundamental losses in charge generation, which require a rather large offset between donors and acceptors to achieve efficient charge separation, limiting the maximum achievable power conversion efficiency to less than 11% for a single junction. Inorganic-based thin-film photovoltaics require the use of highly toxic solvents and high temperatures of over 500°C, making them undesirable for mass production.

[0186] For these reasons, perovskite-based hybrid photovoltaics are an attractive alternative technology since they can be processed below 150 °C, are fully solid-state devices, and have already shown high power conversion efficiencies of over 12%. Perovskite absorbers have been used before in sensitized solar cells as well as in thin-film architectures. In particular, in the latter configuration, perovskite CH 3 NH 3 PbI 3-x Cl x can act as a hybrid sensitizer and electron transporter when processed on an alumina mesostructured scaffold, simply because the electrons transfer directly to the conductive substrate through the conduction band of the perovskite, minimizing the energy loss. In this way, extremely high open circuit voltages of over 1.1 V can be achieved.

[0187] In most perovskite-based photovoltaics, electrons are collected from the FTO substrate, while holes are collected at the metal cathode. This configuration is undesirable for some tandem applications, where holes must be collected at the TCO (transparent conductive oxide) interface. Here, we demonstrate a novel inverted device architecture. This architecture is often used in organic photovoltaics, namely, [6,6]-phenyl C61 butyric acid methyl ester (PC 60 BM) and poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS), and V 2 O 5 and based on n-type and p-type materials commonly used for charge collection in NiO.

[0188] In one embodiment, the optoelectronic device of the present invention comprises a first electrode, a second electrode, and the photoactive region disposed between the first and second electrodes, where the second electrode contacts an n-type region of the photoactive region and the first electrode contacts a p-type region of the photoactive region, where the first electrode comprises a transparent or semi-transparent electrically conductive material and the second electrode comprises aluminum, gold, silver, nickel, palladium or platinum.

[0189] Thus, an optoelectronic device according to the invention may comprise the following regions in the following order: I. A second electrode; II. An n-type region comprising at least one n-type layer; III. A layer of a perovskite semiconductor without open pores; IV. A p-type region comprising at least one p-type layer; and V. First electrode.

[0190] Each of the regions (second electrode, n-type region, layer of perovskite semiconductor without open pores, p-type region and first electrode) may be as defined anywhere herein.

[0191] For example, an optoelectronic device according to the invention may comprise the following regions in the following order: I. a second electrode comprising a metal; II. An n-type region comprising at least one n-type layer; III. A layer of a perovskite semiconductor without open pores; IV. A p-type region comprising at least one p-type layer; and V. A first electrode comprising a transparent conductive oxide.

[0192] For example, an optoelectronic device according to the invention may comprise the following regions in the following order: I. a second electrode comprising a metal, preferably silver or gold; II. An n-type region comprising at least one n-type layer; III. A layer of a perovskite semiconductor without open pores; IV. A p-type region comprising at least one p-type layer; and V. A first electrode comprising a transparent conductive oxide, preferably FTO.

[0193] Any of the components in an inverted device according to the present invention may be as defined elsewhere herein. For example, the perovskite may be a perovskite according to any one of formulas I, Ia, II or IIa above. For example, the perovskite may be a perovskite according to CH 3 NH 3 PbI 3 , C.H. 3 NH 3 PbBr 3 , C.H. 3 NH 3 PbCl 3 , C.H. 3 NH 3 PbF 3 , C.H. 3 NH 3 PbBrI 2 , C.H. 3 NH 3 PbBrCl 2 , C.H. 3 NH 3 PbIBr 2 , C.H. 3 NH 3 PbICl 2 , C.H. 3 NH 3PbClBr 2 , C.H. 3 NH 3 PbI 2 Cl, CH 3 NH 3 SnBrI 2 , C.H. 3 NH 3 SnBrCl 2 , C.H. 3 NH 3 SnF 2 Br, C.H. 3 NH 3 SnIBr 2 , C.H. 3 NH 3 SnICl 2 , C.H. 3 NH 3 SnF 2 I, C.H. 3 NH 3 SnClBr 2 , C.H. 3 NH 3 SnI 2 Cl and CH 3 NH 3 SnF 2 In some embodiments, the second electrode may instead comprise a transparent conductive oxide. For example, both the first electrode and the second electrode may be selected from ITO, FTO, and AZO. When the second electrode comprises a metal such as silver or gold, the thickness of the second electrode may sometimes be from 1 nm to 10 nm. For example, the first electrode may comprise FTO or ITO, and the second electrode may comprise a layer of silver having a thickness of from 1 nm to 10 nm, for example, from 5 nm to 10 nm. The thin layer of silver may be semi-transparent.

[0194] The n-type region in an inverted device can include at least one n-type layer as defined elsewhere herein for a standard, non-inverted device. For example, the n-type layer can be TiO 2 , SnO 2 , ZnO, Nb 2 O 5 , Ta 2 O 5 , WO3 , W 2 O 5 , In 2 O 3 , Ga 2 O 3 , Nd 2 O 3 , PbO, or CdO. In one embodiment, the n-type region can include a dense layer of titanium dioxide. Often, the n-type region includes a dense layer of titanium dioxide and

[60] PCBM ([6,6]-phenyl-C 61 When the n-type region comprises a layer of titanium dioxide and a layer of

[60] PCBM, the dense layer of titanium dioxide is typically adjacent to the second electrode and the layer of

[60] PCBM is typically adjacent to a layer of the perovskite semiconductor without open pores.

[0195] The p-type region in an inverted device can include at least one p-type layer as defined elsewhere herein for a standard, non-inverted device. For example, the p-type layer can include spiro-OMeTAD (2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)9,9'-spirobifluorene), P3HT (poly(3-hexylthiophene)), PCPDTBT (poly[2,1,3-benzothiadiazole-4,7-diyl[4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene-2,6-diyl]]), PVK (poly(N-vinylcarbazole)), PEDOT (poly(3,4-ethylenedioxythiophene)), or PEDOT:PSS (poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate)). Alternatively, the p-type layer may comprise an inorganic hole transporter, for example comprising an oxide of nickel, vanadium, copper or molybdenum. In particular, the p-type region may comprise a layer of spiro-OMeTAD and / or a layer of PEDOT:PSS. In one embodiment, the p-type region comprises a layer of PEDOT:PSS. When the p-type region comprises a layer of a p-type polymeric material (such as PEDOT or PEDOT:PSS), the p-type layer may be crosslinked. The layer is crosslinked to limit the extent to which the layer dissolves in a solution of perovskite precursors during device fabrication, i.e., the polymer is crosslinked to render the polymer (e.g., PEDOT:PSS) insoluble. For example, the p-type region may comprise a p-type layer comprising a polymeric material, where the p-type layer is crosslinked. Sometimes, the p-type region may comprise a layer of PEDOT:PSS, where the layer is crosslinked. The p-type layer may be crosslinked by reacting the layer with a Lewis acid, for example Fe 3+ The p-type region can include a layer of PEDOT:PSS, where FeCl 3 is used to crosslink the layers.

[0196] An optoelectronic device according to the invention may comprise the following regions in the following order: I. a second electrode comprising a metal; II. An n-type region comprising a dense layer of titanium dioxide and a layer of

[60] PCBM; III. A layer of a perovskite semiconductor without open pores; IV. A p-type region comprising a layer of PEDOT:PSS, optionally bridging the layer here; and V. A first electrode comprising a transparent conductive oxide.

[0197] An optoelectronic device according to the invention may comprise the following regions in the following order: I. a second electrode comprising a metal, preferably aluminum, silver or gold; II. An n-type region comprising a dense layer of titanium dioxide and a layer of

[60] PCBM; III. A layer of a perovskite semiconductor without open pores; IV. A p-type region comprising a layer of PEDOT:PSS, optionally bridging the layer here; and V. A first electrode comprising a transparent conductive oxide, preferably FTO.

[0198] For example, an optoelectronic device according to the invention may comprise the following regions in the following order: I. a second electrode comprising aluminum; II. A dense layer of titanium dioxide; III. A layer of

[60] PCBM; IV. A layer of a perovskite semiconductor without open pores; V. A layer of crosslinked PEDOT:PSS, and VI. A first electrode comprising FTO.

[0199] The photoactive region may be the only photoactive region within the device and the optoelectronic device of the present invention may therefore be a single junction device.

[0200] Alternatively, the optoelectronic device of the present invention may be a tandem junction optoelectronic device or a multi-junction optoelectronic device.

[0201] Thus, the optoelectronic element comprises a first electrode, a second electrode, and a photodiode disposed between the first electrode and the second electrode. the photoactive region, and at least one further photoactive region; may include.

[0202] The one or more further photoactive regions may be the same as or different from the photoactive region defined herein above.

[0203] In some embodiments, the one or more further photoactive regions are the same as the photoactive region defined herein above.

[0204] Thus, an optoelectronic device of the present invention may include a first electrode, a second electrode, and a plurality of said photoactive regions disposed between the first electrode and the second electrode.

[0205] When the optoelectronic device of the present invention is a tandem junction or multi-junction device, as will be appreciated by those skilled in the art, the optoelectronic device may include one or more tunnel junctions, each tunnel junction typically being disposed between two photoactive regions.

[0206] Tandem junction optoelectronic devices (or multi-junction optoelectronic devices) according to the present invention can combine the perovskite thin film technology disclosed herein with known technology to achieve optimized performance.

[0207] "All-perovskite" multijunction cells are very attractive, however, even without the need to develop new absorbers, especially when used as the top cell in a tandem junction. 3 NH 3 PbI 3-x Cl xCurrent systems utilizing CIS are already very well set up to interface with crystalline silicon and other thin-film technologies such as CIS, CIGS, and CZTSSe. There is potential to produce optoelectronic devices with efficiencies in excess of 20%. This remarkable aspect does not require a “quantum leap” in the currently demonstrated technology, just a little optimization and effective integration. There are many clear advantages to “embedding” to existing technology; the continued drop in the cost of existing PV will be favorable, the market should be much happier to match “modified silicon technology” rather than an all-new perovskite technology, and finally, a key challenge for the broader PV community is to develop wide-gap top cells for silicon and thin-film technologies. In Fig. 16 and Fig. 17 we give schematics of possible tandem junction device configurations for perovskite on c-Si and perovskite on conventional thin-film.

[0208] In one embodiment, the present invention provides a sensor comprising a first electrode, a second electrode, and a sensor disposed between the first electrode and the second electrode. said photoactive region as defined hereinbefore, and At least one other photoactive region Including, There is provided an optoelectronic device, wherein at least one distinct photoactive region comprises at least one layer of semiconductor material.

[0209] The at least one other photoactive region can be at least one photoactive region other than photoactive regions used in conventional and known optoelectronic and photovoltaic devices, for example, it can be a photoactive region from a crystalline silicon photovoltaic cell or a photoactive region from a conventional thin film gallium arsenide, CIGS, CIS or CZTSSe photovoltaic device.

[0210] In many cases, a tandem optoelectronic device will include the following regions in the following order: I. a first electrode; II. A first photoactive region as defined anywhere previously herein; III. A second photoactive region comprising a layer of semiconductor material; and IV. Second electrode.

[0211] The semiconductor material in region III can be any semiconductor material. The term "semiconductor material," as used herein, refers to a material that has an electrical conductivity that is intermediate in magnitude between that of a conductor and that of an insulator. Typically, a semiconductor material has a conductivity of about 10 3 From 10 -8 Scm -1 Semiconductor materials are materials with electrical conductivity up to 1000 . Standard techniques such as four-probe conductivity measurements can be used to measure electrical conductivity. Examples of semiconductor materials include oxides or chalcogenides of metals or metalloid elements; Group IV compounds; compounds containing Group III and Group V elements; compounds containing Group II and Group VI elements; compounds containing Group I and Group VII elements; compounds containing Group IV and Group VI elements; compounds containing Group V and Group VI elements; compounds containing Group II and Group V elements; ternary or quaternary compound semiconductors; perovskite semiconductors or organic semiconductors. Typical examples of semiconductor materials include oxides of titanium, niobium, tin, zinc, cadmium, copper or lead; chalcogenides of antimony or bismuth; copper zinc tin sulfide; copper zinc tin selenide, copper zinc tin selenide sulfide; copper indium gallium selenide; and copper indium gallium diselenide. Further examples include Group IV compound semiconductors (e.g., silicon carbide); Group III-V semiconductors (e.g., gallium arsenide); Group II-VI semiconductors (e.g., cadmium selenide); Group I-VII semiconductors (e.g., cuprous chloride); Group IV-VI semiconductors (e.g., lead selenide); Group V-VI semiconductors (e.g., bismuth telluride); and Group II-V semiconductors (e.g., cadmium arsenide); ternary or quaternary semiconductors (e.g., copper indium selenide, copper indium gallium diselenide, or copper zinc tin sulfide); perovskite semiconductor materials (e.g., CH 3 NH 3 PbI 3 and C.H. 3 NH 3 PbI 2Cl); and organic semiconductor materials (e.g., conjugated polymeric compounds including polymers such as polyacetylene, polyphenylene, and polythiophene). Examples of organic semiconductors include poly(3,4-ethylenedioxythiophene), 2,2-7,7-tetrakis-N,N-di-p-methoxyphenylamine-9,9-spirobifluorene (spiro-OMeTAD), and conjugated organic polymers such as polyacetylene, polyphenylene, polythiophene, or polyaniline. Examples of materials that are not semiconductor materials include, for example, elemental metals, which are naturally conductors, and electrical insulators or dielectrics, such as silica or calcite.

[0212] The term "oxide," as used herein, means an element that contains at least one oxygen ion (i.e., O 2- ) or divalent oxygen atoms. The terms "metal oxide" and "oxide of metal element" as used herein should be understood to include both oxides containing one metal and also mixed metal oxides. For the avoidance of doubt, mixed metal oxides refer to single oxide compounds containing more than one metal element. Examples of mixed metal oxides include zinc tin oxide and indium tin oxide. Similarly, the terms "metalloid oxide" and "oxide of metalloid element" as used herein should be understood to include oxides containing one metalloid element and also mixed metalloid oxides. For the avoidance of doubt, mixed metalloid oxides refer to single oxide compounds containing more than one metalloid element.

[0213] The term "chalcogenide" as used herein means a compound having a sulfide ion, a selenide ion, or a telluride ion (i.e., S 2- , Se 2- , or Te 2-), or at least one of a divalent sulfur atom, a selenium atom, or a tellurium atom. The terms "metal chalcogenide" and "chalcogenide of a metal element" are to be understood to include chalcogenides containing one metal and also mixed metal chalcogenides. For the avoidance of doubt, mixed metal chalcogenides refer to single chalcogenide compounds containing more than one metal element. Similarly, the terms "metalloid chalcogenides" and "chalcogenides of a metalloid element" as used herein are to be understood to include chalcogenides containing one metalloid and also mixed metalloid chalcogenides. For the avoidance of doubt, mixed metalloid chalcogenides refer to single chalcogenide compounds containing more than one metalloid element.

[0214] Sometimes, the semiconductor material includes an oxide or chalcogenide of a metal or metalloid element. For example, the semiconductor material is composed of an oxide or chalcogenide of a metal or metalloid element. For example, the semiconductor material includes an oxide of titanium, niobium, tin, zinc, cadmium, copper, or lead, or any combination thereof; or a chalcogenide of antimony, bismuth, or cadmium, or any combination thereof. For example, the semiconductor material can include zinc tin oxide; copper zinc tin sulfide; copper indium gallium selenide, or copper indium gallium diselenide.

[0215] In one embodiment, the semiconductor material may be a doped semiconductor, where the impurity element is present at a concentration ranging between 0.01% and 40%. If the impurity element acts as an electron donor, the semiconductor material will be doped to be n-type, and if the impurity element acts as an electron acceptor, the semiconductor material will be doped to be p-type. It is noted that with respect to metal oxides doped with an impurity metalloid element substituting a primary metalloid element, if the valence of the dopant is greater than the valence of the primary metalloid element, the metal oxide will be doped to be n-type, and if the valence of the dopant metalloid element is less than the valence of the primary metalloid element, the metal oxide will be doped to be p-type. Any of the elements described above can be used to dope any of the semiconductor materials described above to different levels of efficacy and effectiveness.

[0216] Thus, in some cases, the semiconductor material includes an oxide or chalcogenide of a metal or metalloid element; a Group IV compound; a compound containing Group III and Group V elements; a compound containing Group II and Group VI elements; a compound containing Group I and Group VII elements; a compound containing Group IV and Group VI elements; a compound containing Group V and Group VI elements; a compound containing Group II and Group V elements; a ternary or quaternary compound semiconductor; or an organic semiconductor.

[0217] In many cases, the semiconductor material comprises silicon, an oxide of titanium, niobium, tin, zinc, cadmium, copper, or lead, an antimony or bismuth chalcogenide, copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide, silicon carbide, gallium arsenide, cadmium selenide, cuprous chloride, lead selenide, bismuth telluride, or cadmium arsenide. When the semiconductor material comprises silicon, the silicon can be monocrystalline, polycrystalline, or amorphous.

[0218] A photoactive region according to the present invention can be in tandem with a traditional silicon solar cell. For example, the semiconductor material can include a layer of crystalline silicon.

[0219] In some embodiments, the optoelectronic device comprises the following regions in the following order: I. a first electrode; II. A first photoactive region, as defined anywhere herein; III. A layer of p-type semiconductor (A); IV. A first layer of an intrinsic semiconductor; A layer of Vp-type semiconductor (B) or a layer of n-type semiconductor (B), VI. A second layer of an intrinsic semiconductor; VII. A layer of n-type semiconductor (C), and VIII. Second electrode.

[0220] Sometimes, an optoelectronic device includes the following regions in the following order: I. a first electrode; II. The first area, III. A layer of a perovskite semiconductor without open pores; IV. The third area, A layer of Vp-type semiconductor (A), VI. A first layer of an intrinsic semiconductor; VII. A layer (B) of a p-type semiconductor or a layer (B) of an n-type semiconductor; VIII. A second layer of an intrinsic semiconductor; IX. A layer of n-type semiconductor (C), and X. a second electrode; wherein the first region is an n-type region comprising at least one n-type layer and the third region is a p-type region comprising at least one p-type layer; or The first region is a p-type region including at least one p-type layer, and the third region is an n-type region including at least one n-type layer.

[0221] Any of the components in this tandem element (e.g., the perovskite, the first region, or the third region) can be as defined anywhere herein. Any of the p-type, n-type, or intrinsic semiconductors mentioned can include any of the semiconductors defined herein that may be p-doped, n-doped, or undoped, as appropriate.

[0222] In many cases, the first region is a p-type region comprising at least one p-type layer, and the third region is an n-type region comprising at least one n-type layer. Thus, the p-type layer will be adjacent to the first electrode, and the perovskite photoactive region according to the invention will be inverted. Typically, light impinging on the device is incident through the first electrode. The n-type region comprising at least one n-type layer can be as defined herein and / or the p-type region comprising at least one p-type layer can be as defined herein.

[0223] In many cases, in the tandem optoelectronic device according to the invention, the layer of p-type semiconductor (A) is a layer of p-type amorphous silicon and / or the layer of n-type semiconductor (C) is a layer of n-type amorphous silicon. Typically, the layer of p-type semiconductor (A) is a layer of p-type amorphous silicon and the layer of n-type semiconductor (C) is a layer of n-type amorphous silicon. In many cases, the first layer of intrinsic semiconductor is a layer of intrinsic amorphous silicon and / or the second layer of intrinsic semiconductor is a layer of intrinsic amorphous silicon. Sometimes, the first layer of intrinsic semiconductor is a layer of intrinsic amorphous silicon and the second layer of intrinsic semiconductor is a layer of intrinsic amorphous silicon. In the tandem device, the layer of p-type semiconductor (B) or the layer of n-type semiconductor (B) can be a layer of p-type crystalline silicon or a layer of n-type crystalline silicon.

[0224] As defined elsewhere herein, the first electrode typically comprises a transparent conductive oxide and / or the second electrode comprises a metal. In many cases, the first electrode typically comprises a transparent conductive oxide and the second electrode comprises a metal. The transparent conductive oxide can be as defined above and is often FTO, ITO, or AZO, typically ITO. The metal can be any metal. In general, the second electrode comprises a metal selected from silver, gold, copper, aluminum, platinum, palladium, or tungsten. This list of metals can also be applied to other cases of the second electrode herein. In many cases, the first electrode material comprises ITO and / or the second electrode comprises silver. Typically, the first electrode material comprises ITO and the second electrode comprises silver.

[0225] A photoactive region according to the invention comprising a layer of perovskite without open pores can be in tandem with a thin film photoactive region, rather than in tandem with a silicon photoactive region. For example, an optoelectronic device can comprise the following regions in the following order: I. a first electrode; II. A first photoactive region as defined anywhere previously herein; III. A second photoactive region comprising a layer of semiconductor material; and IV. A second electrode; Here, the semiconductor material includes a layer of copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide or copper indium selenide. The layer of semiconductor material may be a thin film of semiconductor material.

[0226] In one embodiment, the optoelectronic device comprises the following regions in the following order: I. a first electrode; II. A first photoactive region as previously defined herein; III. A layer of a transparent conductive oxide; IV. A layer of n-type semiconductor (D), V. Layers of copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide or copper indium selenide, and VI. Second electrode.

[0227] For example, an optoelectronic device according to the invention may comprise the following regions in the following order: I. a first electrode; II. The first area, III. A layer of a perovskite semiconductor without open pores; IV. The third area, V. A layer of transparent conductive oxide; VI. A layer of n-type semiconductor (D), VII. Layers of copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide or copper indium selenide, and VIII. A second electrode; wherein the first region is an n-type region comprising at least one n-type layer and the third region is a p-type region comprising at least one p-type layer; or The first region is a p-type region including at least one p-type layer, and the third region is an n-type region including at least one n-type layer.

[0228] The n-type semiconductor layer (D) can include any metal oxide or chalcogenide semiconductor. In many cases, the n-type semiconductor layer (D) includes cadmium sulfide.

[0229] Typically, in a tandem device comprising a thin film of a semiconductor, the first region is an n-type region comprising at least one n-type layer and the third region is a p-type region comprising at least one p-type layer. The n-type region comprising at least one n-type layer may be as defined anywhere herein and / or the p-type region comprising at least one p-type layer may be as defined anywhere herein.

[0230] The first electrode and / or the second electrode can be as defined above. Typically, the first electrode comprises a transparent conductive oxide and / or the second electrode comprises a metal. In many cases, the first electrode comprises a transparent conductive oxide and the second electrode comprises a metal. Typically, the first electrode comprises ITO and / or the second electrode comprises tungsten, or the first electrode comprises ITO and the second electrode comprises tungsten.

[0231] The optoelectronic device of the present invention may be a photovoltaic device; a photodiode; a phototransistor; a photomultiplier tube; a photoresistor; a photodetector; a photosensitive detector; a solid state triode; a cell electrode; a light emitting element; a light emitting diode; a transistor; a solar cell; a laser; or a diode injection laser.

[0232] In a preferred embodiment, the optoelectronic device of the present invention is a photovoltaic device, such as a solar cell.

[0233] The optoelectronic device according to the present invention may be a solar cell.

[0234] In another preferred embodiment, the optoelectronic device of the present invention is a light emitting element, for example a light emitting diode.

[0235] The perovskite compound utilized in the optoelectronic device of the present invention in the layer of open pore free perovskite semiconductor and / or in the first layer is: (a) a first compound comprising (i) a first cation and (ii) a first anion, (b) a second compound comprising (i) a second cation and (ii) a second anion;

[0023] The composition may be produced by a process comprising mixing Here, the first cation and the second cation are as defined herein for the perovskite; and The first anion and the second anion can be the same or different anions.

[0236] A perovskite containing at least one anion selected from halide anions and chalcogenide anions is, for example, (a) a first compound comprising (i) a first cation and (ii) a first anion, (b) a second compound comprising (i) a second cation and (ii) a second anion;

[0023] The composition may be produced by a process comprising mixing Here, the first cation and the second cation are as defined herein for the perovskite; and The first anion and the second anion may be the same or different anions selected from halide anions and chalcogenide anions.

[0237] Typically, the first anion and the second anion are different anions. More typically, the first anion and the second anion are different anions selected from halide anions.

[0238] The perovskite produced by the process can include additional cations or additional anions. For example, the perovskite can include two, three, or four different cations, or two, three, or four different anions. The process for producing a perovskite can thus include mixing additional compounds that include additional cations or additional anions. Additionally or alternatively, the process for producing a perovskite can include mixing (a) and (b) with: (c) a third compound that includes (i) the first cation and (ii) the second anion, or (d) a fourth compound that includes (i) the second cation and (ii) the first anion.

[0239] Typically, in the process for producing perovskites, the second cation in the mixed anion perovskite is a metal cation. More typically, the second cation is a divalent metal cation. For example, the second cation may be Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Typically, the second cation can be selected from Sn 2+ and Pb 2+ Choose from.

[0240] Often in the process for producing perovskites, the first cation in the mixed-anion perovskite is an organic cation.

[0241] Typically, organic cations have the formula (R 1 R 2 R 3 R 4 N) + where R 1 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 2 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 3 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl, and R 4 is hydrogen or unsubstituted or substituted C 1 ~C20 It is alkyl, or unsubstituted or substituted aryl.

[0242] Mainly, in organic cations, R 1 is hydrogen, methyl or ethyl; R 2 is hydrogen, methyl or ethyl; R 3 is hydrogen, methyl or ethyl, and R 4 is hydrogen, methyl or ethyl. For example, R 1 can be hydrogen or methyl; R 2 can be hydrogen or methyl; R 3 can be hydrogen or methyl, and R 4 can be hydrogen or methyl.

[0243] Alternatively, the organic cation may be represented by the formula (R 5 NH 3 ) + where R 5 is hydrogen, or unsubstituted or substituted C 1 ~C 20 For example, R 5 can be methyl or ethyl. Typically, R 5 is methyl.

[0244] Alternatively, the organic cation may be represented by the formula (R 5 R 6 N=CH-NR 7 R 8 ) + where R 5 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 6 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 7 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; and R8 is hydrogen, unsubstituted or substituted C 1 ~C 20 It is alkyl, or unsubstituted or substituted aryl.

[0245] Typically, the cation (R 5 R 6 N=CH-NR 7 R 8 ) + R in 5 is hydrogen, methyl or ethyl; R 6 is hydrogen, methyl or ethyl; R 7 is hydrogen, methyl or ethyl, and R 8 is hydrogen, methyl or ethyl. For example, R 5 can be hydrogen or methyl; R 6 can be hydrogen or methyl; R 7 can be hydrogen or methyl, and R 8 can be hydrogen or methyl.

[0246] Organic cations are, for example, those represented by the formula (H 2 N=CH-NH 2 ) + may have the following structure:

[0247] In the process for producing a perovskite, the perovskite is typically a mixed halide perovskite, where the two or more different anions are two or more different halide anions.

[0248] Typically, in a process for producing perovskite, the perovskite is represented by the chemical formula (I): [A][B][X] 3 (I) Here, [A] is at least one organic cation; [B] is at least one metal cation, and [X] is the at least one anion, and The process is (a) a first compound comprising (i) a metal cation and (ii) a first anion, (b) a second compound comprising (i) an organic cation and (ii) a second anion; Mixing the Here, The first anion and the second anion are different anions selected from a halide anion or a chalcogenide anion.

[0249] The perovskite of formula (I) can, for example, contain one, two, three or four different metal cations, typically one or two different metal cations. The perovskite of formula (I) can, for example, contain one, two, three or four different organic cations, typically one or two different organic cations. The perovskite of formula (I) can, for example, contain two, three or four different anions, typically two or three different anions. The process can therefore include mixing further compounds containing cations and anions.

[0250] Typically, [X] is two or more different halide anions. The first anion and the second anion are thus typically halide anions. Alternatively, [X] can be three different halide ions. Thus, the process can include mixing a third compound with the first compound and the second compound, where the third compound comprises (i) a cation and (ii) a third halide anion, where the third anion is a halide anion different from the first halide anion and the second halide anion.

[0251] Often, in the process for producing perovskite, the perovskite has the chemical formula (IA): AB[X] 3 (IA) Here, A is an organic cation; B is a metal cation, and [X] is the two or more different anions; The process is (a) a first compound comprising (i) a metal cation and (ii) a first halide anion; (b) a second compound comprising (i) an organic cation and (ii) a second halide anion; mixing, wherein The first halide anion and the second halide anion are different halide anions.

[0252] Typically, [X] is two or more different halide anions. Preferably, [X] is two or three different halide anions. More preferably, [X] is two different halide anions. In another embodiment, [X] is three different halide anions.

[0253] Typically, in the process for producing perovskite, the perovskite is formed by a process having the chemical formula (II): ABX 3-y X' y (II) Here, A is an organic cation; B is a metal cation; X is a first halide anion; X' is a second halide anion different from the first halide anion, and y is between 0.05 and 2.95, and The process is (a) a first compound comprising (i) a metal cation and (ii) X, (b) a second compound comprising (i) an organic cation and (ii) X'; Mixing the Here, the ratio of X to X' in the mixture is equal to (3-y):y.

[0254] To achieve the ratio of X to X' equal to (3-y):y, the process can include mixing an additional compound with the first compound and the second compound. For example, the process can include mixing a third compound with the first compound and the second compound, where the third compound includes (i) a metal cation and (ii) X'. Alternatively, the process can include mixing a third compound with the first compound and the second compound, where the third compound includes (i) an organic cation and (ii) X.

[0255] Usually, y is from 0.5 to 2.5, for example from 0.75 to 2.25. Typically, y is from 1 to 2.

[0256] Typically, in a process for producing perovskite, the first compound is BX 2 and the second compound is AX'.

[0257] In many cases, the second compound is represented by the formula (R 5 NH 2 ), where R 5 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl and has the chemical formula HX'. Typically, R 5 can be methyl or ethyl, and often R 5 is methyl.

[0258] Usually, the chemical formula (R 5 NH 2 A compound of formula (R) and a compound of formula HX' are reacted in a 1:1 molar ratio. Often the reaction is carried out under a nitrogen atmosphere and usually in absolute ethanol. Typically, absolute ethanol is about 200 proof. More typically, 15 to 30 ml of a compound of formula (R 5 NH 2) is reacted with about 15 ml to 15 ml of HX', usually in 50 ml to 150 ml of absolute ethanol under a nitrogen atmosphere. The process can also include a step of recovering the mixed-anion perovskite. A rotary evaporator is often used to extract the crystalline AX'.

[0259] Typically, the step of mixing the first compound and the second compound is a step of dissolving the first compound and the second compound in a solvent. The first compound and the second compound can be dissolved in a ratio of 1:20 to 20:1, typically in a ratio of 1:1. Typically, the solvent is dimethylformamide (DMA) or water. When the metal cation is Pb 2+ When the metal cation is Sn, the solvent is usually dimethylformamide. 2+ In this case, the solvent is usually water. The use of DMF or water as the solvent is advantageous since these solvents are not very volatile.

[0260] The perovskite semiconductor layers in the inventive devices can be prepared by solution processing or by deposition in vacuum. Low processing temperatures are important to reduce manufacturing costs and allow processing on plastic substrates and on top of other layers to enable the fabrication of tandem and multi-junction solar cells. Here, the inventors demonstrate that the inventive devices can operate with all layers processed at low temperatures, including the solution processable scaffold.

[0261] The present invention provides a process for manufacturing an optoelectronic device including a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; and a semiconductor layer disposed between the n-type region and the p-type region. a layer of a perovskite semiconductor without open pores; The process includes: (a) providing a first area; (b) disposing a second region over the first region, the second region comprising a layer of a perovskite semiconductor without open pores; and (c) disposing a third region over the second region; where: the first region is an n-type region including at least one n-type layer and the third region is a p-type region including at least one p-type layer; or The first region is a p-type region including at least one p-type layer, and the third region is an n-type region including at least one n-type layer.

[0262] Often the first region is an n-type region including at least one n-type layer and the third region is a p-type region including at least one p-type layer.

[0263] In the process of the present invention, the n-type region, n-type layer, p-type region and p-type layer may be as further defined hereinbefore for the optoelectronic device of the present invention, and the layer of perovskite semiconductor without open pores, and the perovskite semiconductor itself may be as further defined hereinbefore.

[0264] In one embodiment of the process of the present invention, the step (b) of disposing the second region on the first region comprises: forming a solid layer of perovskite on the first region by vapor deposition; Includes.

[0265] In this embodiment, the step of producing a solid layer by vapor deposition typically comprises: (i) exposing a first region to a vapor, the vapor comprising said perovskite or one or more reactants for producing said perovskite; (ii) allowing deposition of a vapor onto the first region to produce a solid layer of the perovskite on the first region; Includes.

[0266] The perovskite in the vapour may be any of the perovskites discussed hereinbefore for the optoelectronic devices of the present invention, and is typically a perovskite of formula (I), (IA) or (II) as defined hereinbefore.

[0267] The one or more reactants for producing the perovskite may include reactants of the type discussed above with respect to the process for synthesizing perovskite compounds.

[0268] Thus, the one or more reactants may be, as defined hereinbefore in relation to the process for producing the perovskite compounds for use in the optoelectronic devices of the present invention: (a) a first compound comprising (i) a first cation and (ii) a first anion; and (b) a second compound comprising (i) a second cation and (ii) a second anion; may include.

[0269] More particularly, the one or more reactants are (a) a first compound comprising (i) a metal cation and (ii) a first anion; (b) a second compound comprising (i) an organic cation and (ii) a second anion. wherein the first anion and the second anion are different anions selected from halide anions or chalcogenide anions, as defined hereinbefore in relation to the process for producing the perovskite compounds for use in the optoelectronic devices of the present invention.

[0270] For example, one or more of the reactants may be (a) a first compound comprising (i) a metal cation and (ii) a first halide anion; (b) a second compound comprising (i) an organic cation and (ii) a second halide anion. where the first halide anion and the second halide anion are different halide anions, as defined hereinbefore in relation to the process for producing the perovskite compounds for use in the optoelectronic devices of the present invention.

[0271] For example, the perovskite to be deposited is CH 3 NH 3 PbI 2 When PbI is Cl, the reactant or reactants are typically (a) PbI 2 and (b) C.H. 3 NH 3 Contains Cl.

[0272] The process generally further comprises generating a vapor at a first location by evaporating the perovskite or the one or more reactants for producing the perovskite. In this step, the perovskite or the one or more reactants for producing the perovskite are typically transferred to a deposition chamber that is then evacuated. The perovskite or the one or more reactants for producing the perovskite are typically then heated.

[0273] The resulting vapor is then contacted with a first region to produce a solid layer of the perovskite thereon, thereby depositing. If reactants are used, they react together in situ to produce the perovskite on the first region.

[0274] Typically, vapor deposition can be continued until the solid layer of perovskite has a desired thickness, for example, 10 nm to 100 μm, or more typically, 10 nm to 10 μm. Preferably, vapor deposition can be continued until the solid layer of perovskite has a thickness of 50 nm to 1000 nm, or for example, 100 nm to 700 nm. For example, deposition can be continued until approximately 100 nm to 300 nm of powder is deposited on the first region.

[0275] Vapor deposition can be continued until the solid layer of perovskite has a thickness of at least 100 nm. Typically, for example, vapor deposition continues until the solid layer of perovskite has a thickness of from 100 nm to 100 μm, or such as from 100 nm to 700 nm.

[0276] The inventors have found that a dual source vapor deposition process allows for a uniform layer of perovskite to be deposited. Vapor deposition is one of the most common methods in large scale manufacturing for depositing thin films of controlled thickness and traditionally refers to the deposition of thin films by coagulation of the desired film material onto a surface in a vacuum. Other deposition methods for inorganic perovskites, such as pulsed laser deposition and chemical solution deposition, have been well studied. (C 6 H 5 C 2 H 4 NH 3 ) 2 PbI 4 Or (C 6 H 5 C 2 H 4 NH 3 ) 2 PbBr 4Hybrid inorganic-organic perovskites such as ZnO, ZnO, and ZnO-based perovskites have been successfully deposited via single-source thermal deposition. However, due to the significant differences in physical and chemical properties between inorganic and organic materials, few deposition methods for hybrid inorganic-organic perovskites have been described, so dual-source thermal deposition was applied to deposit organic and inorganic sources simultaneously but with independent control (VK Dwivedi, JJ Baumberg, and GV Prakash, "Direct deposition of inorganic-organic hybrid semiconductors and their template-assisted microstructures," Materials Chemistry and Physics, vol. 137, no. 3, pp. 941-946, Jan. 2013). Recently, template-assisted electrochemical deposition has been used to fabricate a new kind of hybrid perovskites (C 12 H 25 NH 3 ) 2 PbI 4 It has been proposed to obtain a 2D photonic structure with a 100% purity. It has also been proposed that these materials can be directly hollowed out into 2D photonic structures, which should be very useful in photovoltaic devices. The deposition of hybrid organic-inorganic perovskite materials has always been a challenge, because most organic materials are very volatile and decompose easily, which makes the control of the deposition process more complicated.

[0277] In one embodiment, the step (b) of disposing the second region over the first region comprises: The method includes producing a solid layer of perovskite by vapor deposition, where the vapor deposition is a dual-source vapor deposition.

[0278] The term "dual source vapor deposition," as used herein, refers to a vapor deposition process in which the vapor deposited on a substrate contains two or more components derived from two separate sources. Typically, a first source will produce a vapor containing a first component and a second source will produce a vapor containing a second component. Although dual source deposition is usually preferred, dual source vapor deposition can also be extended to include three-source and four-source vapor deposition.

[0279] In one embodiment, the step (b) of disposing the second region over the first region comprises: (i) exposing a first region to a vapor, the vapor comprising two reactants for producing the perovskite; and (ii) allowing deposition of a vapor onto the first region to produce a solid layer of the perovskite on the first region; Including, The method further includes (i) evaporating a first reactant from a first source and evaporating a second reactant from a second source to produce the vapor comprising two reactants for producing the perovskite.

[0280] The reactants can be as defined herein for the production of perovskites. The vapor can alternatively contain three or more reactants. The two sources are typically placed at the same distance from the first region, often between 10 cm and 40 cm.

[0281] In many cases, the first reactant comprises a first compound comprising (i) a first cation and (ii) a first anion; and the second reactant comprises a second compound comprising (i) a second cation and (ii) a second anion. In some cases, the first cation will be a metal cation here. In some cases, the second cation will be an organic cation here. Thus, the first reactant can comprise a first compound comprising (i) a metal cation and (ii) a first anion; and the second reactant can comprise a second compound comprising (i) an organic cation and (ii) a second anion. Preferably, the metal cation is a divalent metal cation. For example, the metal cation can be Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Among these cations, the divalent metal cation can be selected from Pb 2+ Or Sn 2+ It is preferable that:

[0282] In most cases, organic cations have the formula (R 1 R 2 R 3 R 4 N) + where R 1 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 2 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 3is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl, and R 4 is hydrogen or unsubstituted or substituted C 1 ~C 20 It is alkyl, or unsubstituted or substituted aryl.

[0283] The organic cation can be as defined elsewhere herein. In many cases, the organic cation has the formula (R 5 NH 3 ) + where R 5 is hydrogen, or unsubstituted or substituted C 1 ~C 20 For example, an organic cation may have the formula (R 5 NH 3 ) + where R 5 is methyl, ethyl, propyl or butyl, preferably methyl or ethyl. In some cases, the organic cation can be a methylammonium cation.

[0284] Alternatively, the organic cation may be represented by the formula (R 5 R 6 N=CH-NR 7 R 8 ) + where R 5 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 6 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 7 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; and R 8 is hydrogen, unsubstituted or substituted C 1 ~C20 It is alkyl, or unsubstituted or substituted aryl.

[0285] Typically, the cation (R 5 R 6 N=CH-NR 7 R 8 ) + R in 5 is hydrogen, methyl or ethyl; R 6 is hydrogen, methyl or ethyl; R 7 is hydrogen, methyl or ethyl, and R 8 is hydrogen, methyl or ethyl. For example, R 5 can be hydrogen or methyl; R 6 can be hydrogen or methyl; R 7 can be hydrogen or methyl, and R 8 can be hydrogen or methyl.

[0286] Organic cations are, for example, those represented by the formula (H 2 N=CH-NH 2 ) + may have the following structure:

[0287] The first anion and the second anion can be any anion, but are typically selected from halide ions (e.g., fluoride, chloride, bromide, and iodide) or chalcogenide ions (e.g., sulfide, selenide, and telluride). In many cases, the perovskite will be a mixed halide perovskite or a mixed chalcogenide perovskite, and the first anion and the second anion are different anions selected from halide ions or chalcogenide ions. Preferably, the first anion and the second anion are halide anions. Typically, the first anion and the second anion are different anions selected from halide anions. For example, the first anion and the second anion can be one of the following pairs: (first anion:second anion):(fluoride anion:chloride anion), (chloride anion:fluoride anion), (fluoride anion:bromide anion), (bromide anion:fluoride anion), (fluoride anion:iodide anion), (iodide anion:fluoride anion), (chloride anion:bromide anion), (bromide anion:chloride anion), (chloride anion:iodide anion), (iodide anion:chloride anion), (bromide anion:iodide anion), or (iodide anion:bromide anion).

[0288] In some embodiments, the first reactant will include a metal dihalide and the second reactant will include a halide salt of an organic acid. For example, the first reactant may include BX 2 and the second reactant can include a second compound that is AX', where B is a first cation, X is a first anion, A is a second cation, and X' is a second anion. Each of the cations and anions can be as defined above. Sometimes the first reactant can include a first compound that is BX 2 and the second reactant comprises a second compound, AX′, where B is Ca 2+, Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ is a cation selected from X is F - , Cl - , Br - and I - an anion selected from A is a compound represented by the chemical formula (R 5 NH 3 ) + where R 5 is hydrogen or unsubstituted or substituted C 1 ~C 20 is alkyl, X' is F - , Cl - , Br - and I - and X and X' are different anions.

[0289] The first reactant may include a lead halide or a tin halide and the second reactant may include a methylammonium halide or an ethylammonium halide, where the halide ions in the first and second reactants are different. Often, the first reactant includes tin fluoride and the second reactant includes methylammonium chloride, methylammonium bromide, or methylammonium iodide; the first reactant comprises lead chloride or tin chloride and the second reactant comprises methylammonium bromide or methylammonium iodide; the first reactant comprises lead bromide or tin bromide and the second reactant comprises methylammonium chloride or methylammonium iodide; or The first reactant comprises lead iodide or tin bromide, and the second reactant comprises methylammonium chloride or methylammonium bromide.

[0290] Preferably, the first reactant comprises lead chloride and the second reactant comprises methylammonium iodide.

[0291] These pairs of compounds are applicable to alternative deposition methods of perovskites, such as solution deposition.

[0292] Alternatively, A can be an inorganic monovalent cation. For example, A can be Cs + When A is inorganic, the two halide anions in each reactant can be the same or different. For example, the first reactant can be a first compound BX 2 and the second reactant can comprise a second compound that is AX, where B is Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ is a cation selected from X is F - , Cl - , Br - and I - is an anion selected from A is Cs + and X' is F - , Cl - , Br - and I - and X and X' are the same or different.

[0293] Dual vapor deposition using these reactants produces perovskites of formula (IB) as defined above, e.g., CsSnBr 3 Alternatively, it is possible to produce a layer of CsSnBr 3-y I y where y is as defined in formula (II) above.

[0294] Dual vapor deposition allows the deposition rate of each component (here given in angstroms per second) to be controlled, thus leading to a more controlled deposition. Typically, the deposition rate of the first reactant (optionally including metal cations) is from 0.1 to 10 Å / s, or from 0.1 to 5 Å / s, and the deposition rate of the second reactant (optionally including organic cations) is from 1 to 20 Å / s, or from 1 to 10 Å / s. By varying the length of time the deposition is carried out, the amount of perovskite deposited can be controlled. Typically, the vapor deposition (in either the single source or dual source case) can be carried out for 5 to 60 minutes, or from 20 to 40 minutes. The deposition time will depend on the deposition rate used. In many cases, an excess of the second component is preferred, and the molar ratio of the deposited first reactant to the second reactant can be from 1:1 to 1:16, or from 1:4 to 1:16. Once the desired layer thickness is obtained, the vapor deposition can be stopped.

[0295] Vapor deposition is generally performed at 10 -2 Pa(10 -4 mbar), e.g., less than 10 -3 Pa(10 -5 The step of depositing the second region onto the first region by vapor deposition typically further comprises (iii) heating the solid layer of perovskite thus produced.

[0296] The step of heating the solid layer of perovskite typically includes heating the solid layer of perovskite in an inert atmosphere. Typically, the temperature to which the solid layer of perovskite is heated does not exceed 150°C. Thus, the solid layer of perovskite can be heated at a temperature of 30°C to 150°C, and preferably at a temperature of 40°C to 110°C. The solid layer of perovskite can be heated at said temperature until the solid layer of perovskite has the desired semiconducting properties. Typically, the solid layer of perovskite is heated for at least 30 minutes, preferably at least 1 hour. In some embodiments, the solid layer of perovskite is heated until the desired semiconducting properties are obtained, which can be measured by routine methods for measuring electrical conductivity and resistivity. The solid layer of perovskite is heated, in some cases, until a color change is observed, which indicates that the desired semiconducting properties have been obtained. CH 3 NH 3 PbI 2 In the case of Cl perovskites, the color change is typically from yellow to brown.

[0297] A second region can be disposed on the first region by a process that includes disposing a solid layer of a first compound (first perovskite precursor) on the first region and then treating the disposed layer with a solution of a second compound (second perovskite precursor). This can be referred to as a "two-step process." A solid layer of a first perovskite precursor can be disposed by vacuum deposition. This solid layer is then treated with a solution of a second perovskite precursor. The second precursor in the solution then reacts with the existing solid layer of the first perovskite precursor to produce a solid layer of perovskite. For example, a solid layer of a first perovskite precursor solution can be treated with a solution containing the second perovskite precursor by immersing the solid layer of the first perovskite precursor in a solution containing the second perovskite precursor. The solid layer of the first perovskite precursor can also be treated by disposing a solution containing a second perovskite precursor on top of the solid layer of the first perovskite precursor.

[0298] The first perovskite precursor is a first compound comprising (i) a first cation and (ii) a first anion, and the second perovskite precursor is a second compound comprising (i) a second cation and (ii) a second anion. The first cation and second cation are generally as defined herein for perovskites, and the first anion and second anion may be the same or different and may be as defined herein for the first anion and second anion.

[0299] In one embodiment, the step (b) of disposing the second region over the first region comprises: (i) exposing the first region to a vapor, the vapor including a first perovskite precursor compound, allowing deposition of the vapor on the first region to produce a solid layer of the first perovskite precursor compound on the first region; and (ii) treating the resulting solid layer of a first perovskite precursor compound with a solution comprising a second perovskite precursor compound, thereby reacting the first perovskite precursor compound with the second perovskite precursor compound to produce said layer of a perovskite semiconductor without open porosity; where The first perovskite precursor compound comprises (i) a first cation and (ii) a first anion, and the second perovskite precursor compound comprises (i) a second cation and (ii) a second anion.

[0300] The first cation, the first anion, the second cation, and the second anion may be as defined elsewhere herein for perovskites.

[0301] In some cases, the first cation herein will be a metal cation. In some cases, the second cation herein will be an organic cation. Thus, the first compound can include (i) a metal cation and (ii) a first anion; and the second compound can include (i) an organic cation and (ii) a second anion. Preferably, the metal cation is a divalent metal cation. For example, the metal cation can be Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ Among these cations, the divalent metal cation can be selected from Pb 2+ Or Sn 2+ It is preferable that:

[0302] The first anion and the second anion, which may be the same or different, can be any anion, but are typically selected from halide ions (e.g., fluoride, chloride, bromide, and iodide) or chalcogenide ions (e.g., sulfide, selenide, and telluride).

[0303] In many cases, the perovskite produced will be a mixed halide perovskite or a mixed chalcogenide perovskite, and the first anion and the second anion are different anions selected from halide ions or chalcogenide ions.

[0304] Preferably, the first anion and the second anion are halide anions. Typically, the first anion and the second anion are different anions selected from halide anions. For example, the first anion and the second anion can be one of the following pairs: (first anion:second anion):(fluoride anion:chloride anion), (chloride anion:fluoride anion), (fluoride anion:bromide anion), (bromide anion:fluoride anion), (fluoride anion:iodide anion), (iodide anion:fluoride anion), (chloride anion:bromide anion), (bromide anion:chloride anion), (chloride anion:iodide anion), (iodide anion:chloride anion), (bromide anion:iodide anion), or (iodide anion:bromide anion).

[0305] The organic cation is represented by (R 1 R 2 R 3 R 4 N) + , (R 5 NH 3 ) + , or (R 5 R 6 N=CH-NR 7 R 8 ) + You can choose from R1 From R 8 may be as defined above.

[0306] In many cases, the first compound has the formula BX 2 and the second compound has the formula AX', where B is Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ is a cation selected from X is F - , Cl - , Br - and I - is an anion selected from A is a compound represented by the chemical formula (R 5 NH 3 ) + where R 5 is hydrogen or unsubstituted or substituted C 1 ~C 20 is alkyl, X' is F - , Cl - , Br - and I - and X and X' are the same or different anions.

[0307] In many cases, the first perovskite precursor compound can be selected from lead fluoride, lead chloride, lead bromide, lead iodide, tin fluoride, tin chloride, tin bromide, or tin iodide. Typically, it is lead chloride or lead iodide. In many cases, the second perovskite precursor compound is selected from methylammonium fluoride, methylammonium chloride, methylammonium bromide, methylammonium iodide, ethylammonium fluoride, ethylammonium chloride, ethylammonium bromide, or ethylammonium iodide. Typically, it is methylammonium iodide.

[0308] Typically, vapor deposition of the first perovskite precursor compound may be continued until the solid layer of the first compound has a desired thickness, for example from 10 nm to 100 μm, or more typically from 10 nm to 10 μm. Preferably, vapor deposition may be continued until the solid layer of the first compound has a thickness of from 50 nm to 1000 nm, or for example from 100 nm to 700 nm. For example, deposition may be continued until approximately 100 nm to 300 nm of the first compound has been deposited onto the first region.

[0309] Vapor deposition may continue until the solid layer of the first perovskite precursor compound has a thickness of from 100 nm to 100 μm, or from 100 nm to 700 nm.

[0310] The rate of deposition of the first compound can be from 0.1 to 10 Å / s, or from 1 to 5 Å / s. -2 Pa(10 -4 mbar), e.g., less than 10 -3 Pa(10 -5 The deposition is carried out in a chamber having a pressure of less than 1000 MPa (mbar). The temperature at which the first compound is deposited can be from 200° C. to 500° C., or from 250° C. to 350° C.

[0311] Typically, step (iii) of exposing the resulting solid layer of the first compound to a solution comprising a second compound to allow the generation of a second region comprises immersing the substrate comprising the solid layer of the first compound in a solution comprising the second compound for a sufficient time to form the second region, i.e. a layer of perovskite semiconductor without open pores. Step (iii) may comprise immersing the substrate comprising the solid layer of the first compound in a solution comprising the second compound for 1 to 60 minutes, or 5 to 15 minutes. Immersing the substrate comprising the solid layer of the first compound in a solution comprising the second compound may be referred to as dip coating.

[0312] The solution comprising the second perovskite precursor compound comprises a solvent and a second compound. The solvent may be any solvent defined herein. The solvent may be dimethylformamide, ethanol or isopropanol. The solvent may be isopropanol. The concentration of the second compound in the solvent may be from 5 to 50 mg / ml, or from 10 to 30 mg / ml.

[0313] After contacting the resulting solid layer of the first perovskite precursor compound with a solution containing the second compound to allow for the generation of the second regions (e.g., by dip coating), the substrate may be annealed. For example, the substrate may be heated to 80° C. to 200° C., or 100° C. to 150° C. The substrate may be heated for 1 to 60 minutes, or 5 to 15 minutes. The substrate may be annealed in a nitrogen atmosphere.

[0314] A solution deposition method can be used to dispose the second region over the first region. Thus, in some embodiments, step (b) of disposing the second region over the first region includes: (i) disposing one or more precursor solutions over the first region, the one or more precursor solutions comprising the perovskite dissolved in a solvent or one or more reactants for producing the perovskite dissolved in one or more solvents; and (ii) removing the one or more solvents to produce a solid layer of the perovskite on the first region; Includes.

[0315] Again, the perovskite may be any of the perovskites discussed hereinbefore for the optoelectronic devices of the present invention, and is typically a perovskite of formula (I), (IA) or (II) as defined hereinbefore.

[0316] Also, the one or more reactants for producing the perovskite may include reactants of the type discussed above for the process for synthesizing perovskite compounds.

[0317] Thus, the reactant or reactants may be selected from the group consisting of: (a) a first compound comprising (i) a first cation and (ii) a first anion; and (b) a second compound comprising (i) a second cation and (ii) a second anion; may include.

[0318] More particularly, the one or more reactants are (a) a first compound comprising (i) a metal cation and (ii) a first anion; (b) a second compound comprising (i) an organic cation and (ii) a second anion; and wherein the first anion and the second anion are different anions selected from halide anions or chalcogenide anions as defined hereinbefore in relation to the process for producing the perovskite compounds for use in the optoelectronic devices of the present invention. The organic cation may be as defined hereinbefore in relation to the process for producing the perovskite.

[0319] For example, one or more of the reactants may be (a) a first compound comprising (i) a metal cation and (ii) a first halide anion; (b) a second compound comprising (i) an organic cation and (ii) a second halide anion; and where the first halide anion and the second halide anion are different halide anions, as defined hereinbefore in relation to the process for producing the perovskite compounds for use in the optoelectronic devices of the present invention.

[0320] For example, the perovskite to be deposited is CH 3 NH 3 PbI 2 When PbI is Cl, the reactant or reactants are typically (a) PbI 2 and (b) C.H. 3 NH 3 Contains Cl.

[0321] Typically, the step (b) of disposing the second region on the first region comprises: (i) disposing a precursor solution over a first region, the precursor solution including the perovskite dissolved in a solvent; and (ii) removing the solvent to produce a solid layer of perovskite on the first region; Includes.

[0322] The perovskite may be any of the perovskites discussed hereinbefore for the optoelectronic device of the present invention, and is typically a perovskite of formula (I), (IA) or (II) as defined hereinbefore.

[0323] Typically, the steps of (i) disposing a precursor solution on the first region and (ii) removing the solvent comprise spin-coating or slot-die-coating one or more precursor solutions onto the first region to produce said solid layer of perovskite on the first region. Typically, said coating is performed in an inert atmosphere, for example under nitrogen. Spin-coating is typically performed at a speed of 1000 to 2000 rpm. Spin-coating is typically performed for 30 seconds to 2 minutes.

[0324] To produce the solid layer of perovskite on a first region, one or more precursor solutions may be deposited by spin coating onto the first region.

[0325] The steps of disposing one or more precursor solutions over the first region and removing one or more solvents are performed until the solid layer of perovskite has a desired thickness, for example from 10 nm to 100 μm, more typically from 10 nm to 10 μm. For example, the steps of disposing one or more precursor solutions over the first region and removing one or more solvents can be performed until the solid layer of perovskite has a thickness of from 50 nm to 1000 nm, or for example from 100 nm to 700 nm.

[0326] The steps of disposing one or more precursor solutions over the first region and removing one or more solvents may be performed until a solid layer of the perovskite has a thickness of from 100 nm to 100 μm, or from 100 nm to 700 nm.

[0327] The step of disposing the second region on the first region (by solution deposition) typically further comprises (iii) heating the solid layer of perovskite thus formed.

[0328] The step of heating the solid layer of perovskite typically involves heating the solid layer of perovskite in an inert atmosphere. Typically, the temperature to which the solid layer of perovskite is heated does not exceed 150°C. Thus, the solid layer of perovskite can be heated at a temperature of 30°C to 150°C, and preferably at a temperature of 40°C to 110°C. The solid layer of perovskite can be heated at said temperature until the solid layer of perovskite has the desired semiconducting properties. Typically, the solid layer of perovskite is heated for at least 30 minutes, preferably at least 1 hour. In some embodiments, the solid layer of perovskite is heated until the desired semiconducting properties are obtained, which can be measured by routine methods for measuring electrical conductivity and resistivity. The solid layer of perovskite is heated, in some cases, until a color change is observed, which indicates that the desired semiconducting properties have been obtained. CH 3 NH 3 PbI 2 In the case of Cl perovskites, the color change is typically from yellow to brown.

[0329] In some embodiments of the process of the present invention (e.g. when the photoactive region of the device being fabricated does not have a scaffold material), the second region comprises the layer of the perovskite semiconductor without any open pores.

[0330] In another embodiment of the process of the present invention, the photoactive region is, in any manner, the n-type region, The p-type region and a semiconductor layer disposed between the n-type region and the p-type region. (i) a first layer comprising a scaffold material and a perovskite semiconductor; and (ii) a capping layer disposed on the first layer, the capping layer being the layer of a perovskite semiconductor without open pores; wherein the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer; And the process is (a) providing said first region; (b) disposing said second region over the first region, wherein the second region comprises: (i) a first layer comprising a scaffold material and a perovskite semiconductor; and (ii) a capping layer on said first layer, the capping layer being said layer of a perovskite semiconductor without open pores, wherein the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer; and (c) disposing said third region over the second region; Includes.

[0331] Typically, the scaffold material is porous and the first layer comprises the perovskite semiconductor disposed within the pores of the scaffold material. Thus, typically in this embodiment, step (b) of disposing the second region on the first region comprises: (i) disposing a scaffolding material over a first region; and (ii) disposing the perovskite into the pores of a scaffold material to produce the first layer, and further disposing the perovskite onto the first layer to produce the capping layer. Typically, "disposing" the perovskite into the pores of a scaffold material and "further disposing" the perovskite onto the first layer are performed together in a single step, for example by a solution deposition step or by vapor deposition. These are typically performed by solution deposition.

[0332] Typically, the step (i) of disposing a scaffolding material over the first region comprises: Placing a scaffold composition onto a first region, the scaffold composition comprising a scaffold material, one or more solvents, and optionally a binder, and removing one or more solvents and, when present, the binder is included.

[0333] The binder is typically a polymeric binder such as, for example, ethyl cellulose.

[0334] This step typically includes screen printing, doctor blading, slot die coating, or spin coating the scaffold composition onto the first region.

[0335] The film is then typically heated to a temperature around 500 °C (usually held for around 30 minutes) (high temperature sintering) to decompose and remove any polymeric binders present, or if there is no binder, it is typically heated to around 120 °C and held for around 90 minutes (low temperature sintering). The substrate is then typically cooled in preparation for perovskite solution deposition.

[0336] Thus, typically, step (i) of placing the scaffold material onto the first region further includes heating the scaffold composition.

[0337] What is important for the low temperature treatment of the mesoporous scaffold layer is that there is no thermally decomposable polymeric binder in the nanoparticle paste during deposition. Instead, the nanoparticles are deposited from a colloidal dispersion in one or more solvents. At low temperatures, adhesion between particles and to the substrate is thought to proceed by dehydration of surface hydroxyl groups [T. Miyasaka et al., Journal of Electrochemical Society, vol. 154, p. A455, 2007]. The inventors have also shown that it is possible to adjust the porosity by mixing two solvents in a dispersion having different viscosities and boiling points.

[0338] Thus, in a preferred embodiment, the scaffolding composition does not include a binder and the temperature to which the scaffolding composition is heated does not exceed 150°C.

[0339] Thus, typically, step (i) of disposing a scaffolding material over the first region comprises: disposing a scaffolding composition onto the first region, the scaffolding composition comprising a scaffolding material and one or more solvents; and removing one or more solvents; Includes.

[0340] Typically, step (i) of disposing a scaffolding material over the first region further comprises heating the scaffolding composition to a temperature not exceeding 150° C. Typically, the scaffolding composition is heated to a temperature of from 60° C. to 150° C. The scaffolding composition is heated at said temperature for a suitable period of time, for example until all solvent is removed. Typically, the scaffolding composition is heated at said temperature for at least 30 minutes, more typically for at least 1 hour, or for at least 90 minutes.

[0341] Typically, step (i) of disposing a scaffolding material over the first region is carried out until the scaffolding material disposed over the first region has a desired thickness, for example from 5 nm to 500 nm, preferably from 30 nm to 200 nm.

[0342] The scaffold material utilized in the scaffold composition can be as defined above with respect to the optoelectronic devices of the present invention. In most cases, the scaffold material utilized is titania or alumina.

[0343] The one or more solvents utilized in the scaffold composition can include a mixture of two or more solvents having different viscosities and boiling points, for example, a mixture of two solvents having different viscosities and boiling points. The use of two or more solvents having different viscosities and boiling points is advantageous because the inventors have shown that it is possible to tailor the porosity of the scaffold material disposed over the first region by varying the ratio of the two or more solvents. The two or more solvents can include, for example, two or more different alcohols, for example, two different alcohols. Thus, for example, the two or more solvents can include two solvents selected from ethanol, propanol, butanol, and terpineol, or from ethanol, iso-propanol, tertiary butanol, and terpineol.

[0344] Typically, step (ii) of disposing the perovskite into the pores of a scaffold material to produce the first layer and further disposing the perovskite onto the first layer to produce the capping layer are carried out until the capping layer has a desired thickness, for example a thickness of from 10 nm to 100 μm, or more typically a thickness of from 10 nm to 10 μm, preferably a thickness of from 50 nm to 1000 nm, or such as from 100 nm to 700 nm.

[0345] A solution deposition method can be used to dispose the perovskite into the pores of a scaffold material to produce the first layer and to further dispose the perovskite onto the first layer to produce the capping layer. Thus, in some embodiments, step (ii) of disposing the perovskite into the pores of a scaffold material to produce the first layer and further disposing the perovskite onto the first layer to produce the capping layer can include: disposing one or more precursor solutions onto the scaffold material, the one or more precursor solutions including the perovskite dissolved in a solvent or one or more reactants for producing the perovskite dissolved in one or more solvents; and removing the one or more solvents to produce a solid perovskite within the pores of the scaffold material and a solid capping layer of perovskite disposed on the first layer; Includes.

[0346] The perovskite may be any of the perovskites discussed hereinbefore in relation to the optoelectronic device of the present invention, and is typically a perovskite of formula (I), (IA) or (II) as defined hereinbefore.

[0347] Also, the one or more reactants for producing the perovskite may include reactants of the type discussed above with respect to the process for synthesizing perovskite compounds.

[0348] Thus, the one or more reactants may be selected from the group consisting of: (a) a first compound comprising (i) a first cation and (ii) a first anion; and (b) a second compound comprising (i) a second cation and (ii) a second anion; may include.

[0349] More particularly, the one or more reactants are (a) a first compound comprising (i) a metal cation and (ii) a first anion; (b) a second compound comprising (i) an organic cation and (ii) a second anion; wherein the first anion and the second anion are different anions selected from halide anions or chalcogenide anions, as defined hereinbefore in relation to the process for producing the perovskite compounds for use in the optoelectronic devices of the present invention.

[0350] For example, the reactant or reactants may be, as defined hereinbefore in relation to the process for producing the perovskite compounds for use in the optoelectronic devices of the present invention: (a) a first compound comprising (i) a metal cation and (ii) a first halide anion; (b) a second compound comprising (i) an organic cation and (ii) a second halide anion, where the first halide anion and the second halide anion are different halide anions.

[0351] For example, the perovskite to be deposited is CH 3 NH 3 PbI 2 When PbI is Cl, the reactant or reactants are typically (a) PbI 2 and (b) C.H. 3 NH 3 Contains Cl.

[0352] Typically, the step (ii) of disposing the perovskite into pores of a scaffold material to form the first layer and further disposing the perovskite onto the first layer to form the capping layer comprises: disposing a precursor solution over a scaffold material, the precursor solution including the perovskite dissolved in a solvent; and removing the solvent to produce a solid perovskite within the pores of the scaffold material and a solid capping layer of perovskite disposed on the first layer; Includes.

[0353] The perovskite may be any of the perovskites discussed hereinbefore in relation to the optoelectronic device of the present invention, and is typically a perovskite of formula (I), (IA) or (II) as defined hereinbefore.

[0354] Typically, the steps of disposing the precursor solution onto the scaffold material and removing the one or more solvents include spin-coating or slot-die-coating the one or more precursor solutions onto the scaffold material to produce the solid perovskite within the pores of the scaffold material and the solid capping layer of perovskite disposed on the first layer. Typically, coating is performed in an inert atmosphere, e.g., under nitrogen. Spin-coating can be performed at speeds of, e.g., 1000 to 2000 rpm. Spin-coating is typically performed for 30 seconds to 2 minutes.

[0355] The steps of disposing one or more precursor solutions onto the scaffolding material and removing one or more solvents are performed until a solid capping layer of the perovskite has a desired thickness, for example 10 nm to 100 μm, or more typically 10 nm to 10 μm, or for example 50 nm to 1000 nm, preferably 100 nm to 700 nm.

[0356] Typically, the step (b) of disposing the second region over the first region further comprises (iii) heating the perovskite.

[0357] The step of heating the perovskite usually involves heating the perovskite in an inert atmosphere, for example under nitrogen. Typically, the temperature to which the perovskite is heated does not exceed 150°C. Thus, the perovskite can be heated at a temperature between 30°C and 150°C, and preferably between 40°C and 110°C. The perovskite can be heated at said temperature until the perovskite has the desired semiconducting properties. Usually, the perovskite is heated for at least 30 minutes, preferably at least 1 hour. In some embodiments, the perovskite is heated until it obtains the desired semiconducting properties, which can be measured by routine methods for measuring electrical conductivity and resistivity. The perovskite is heated, in some cases, until a color change is observed, which indicates that the desired semiconducting properties have been obtained. CH 3 NH 3 PbI 2 In the case of Cl perovskites, the color change is typically from yellow to brown.

[0358] Typically, in the process of the present invention for manufacturing an optoelectronic device, the first region is disposed on the first electrode, i.e. the first region is typically already disposed on the first electrode.

[0359] The process of the present invention for manufacturing an optoelectronic device comprises any method comprising: Disposing a first region over the first electrode. The method may further include steps.

[0360] This step is generally performed prior to the step of disposing the second region over the first region.

[0361] The first and second electrodes are an anode and a cathode, one or both of which are transparent to allow light to penetrate. The selection of the first and second electrodes can depend on the structure type.

[0362] Typically, the first electrode on which the second region is placed is tin oxide, more typically fluorine-doped tin oxide (FTO), which is usually a transparent or semi-transparent material. Thus, the first electrode is usually transparent or semi-transparent, typically comprising FTO. Typically, the thickness of the first electrode is 200 nm to 600 nm, more typically 300 nm to 500 nm. For example, the thickness can be 400 nm. Typically, the FTO is coated onto a glass sheet. Often, the FTO-coated glass sheet is etched with zinc powder and acid to produce the required electrode pattern. Typically, the acid is HCl. Often, the concentration of HCl is about 2 molar. Typically, the sheet is washed and then usually treated under oxygen plasma to remove any organic residues. Usually, the treatment under oxygen plasma is for 1 hour or less, typically for about 5 minutes. The first and second electrodes can be as described anywhere herein, for example, the first electrode can be composed of FTO, ITO, or AZO.

[0363] The steps of disposing the first region on the first electrode and disposing the third region on the second region include deposition of a p-type region and an n-type region, i.e. deposition of one or more p-type layers and deposition of one or more n-type layers. The p-type region and the n-type region and the one or more p-type layers and the one or more n-type layers may be as further defined hereinbefore.

[0364] The step of depositing a layer of a p-type or n-type inorganic compound can include, for example, depositing the layer by spin-coating or by slot-die coating of the compound or its precursor, or by spray pyrolysis. For example, a dense layer of titania can be produced by spin-coating a (weakly) acidic titanium isopropoxide sol in a suitable solvent, such as ethanol. Such a sol can be prepared by mixing titanium isopropoxide with a solution of HCl in absolute ethanol. After spin-coating, the layer is typically dried at a temperature not exceeding 150° C. Optionally, the dense layer is then heated to 500° C. for 30 minutes on a hotplate in air. Alternatively, such a dense layer can be produced by spray pyrolysis deposition. This typically involves the deposition of a solution containing titanium diisopropoxide bis(acetylacetonate) at a temperature of between 200 and 300° C., often at a temperature of about 250° C. Usually the solution contains titanium diisopropoxide bis(acetylacetonate) and ethanol, typically in a ratio of 1:5 to 1:20, more typically about 1:10.

[0365] Such methods can be applied to other p-type or n-type inorganic materials to produce n-type and p-type layers in optoelectronic devices of the present invention.

[0366] The deposition of organic, molecular or polymeric hole or electron transporter materials can be achieved by spin-coating a solution of the material in a suitable solvent. The p-type hole transporter, e.g., spiro-OMeTAD, is typically dissolved in chlorobenzene. Usually, the concentration of spiro-OMeTAD in chlorobenzene is from 150 to 225 mg / ml, more typically the concentration is about 180 mg / ml. Additives can be added to the hole or electron transporter materials. The additives can be, for example, tBP, Li-TFSi, ionic liquids or ionic liquids with mixed halides.

[0367] The present process for manufacturing an optoelectronic device may further include (d) disposing a second electrode over the third region.

[0368] Typically, the second electrode comprises a high work function metal, such as gold, silver, nickel, palladium or platinum, typically silver. Typically, the second electrode has a thickness of 50 to 250 nm, more typically 100 to 200 nm. For example, the second electrode may have a thickness of 150 nm.

[0369] The second electrode is disposed over the third region, typically by vapor deposition. Often, the step of creating the second electrode involves placing a film containing a hole transport material in a thermal evaporator. Usually, the step of creating the second electrode involves deposition of the second electrode through a shadow mask under high vacuum. Typically, the vacuum is at 10 -4 Pa(10 -6 mBar).

[0370] The second electrode can be, for example, an electrode having a thickness of from 100 to 200 nm. Typically, the second electrode is an electrode having a thickness of from 150 nm.

[0371] Alternatively, the inventive process for manufacturing an optoelectronic device may be a process for manufacturing an inverted optoelectronic device.

[0372] Accordingly, the present invention provides a process for fabricating an inverted optoelectronic device comprising a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; and a semiconductor layer disposed between the n-type region and the p-type region. a layer of a perovskite semiconductor without open pores; The process includes: (a) providing a first area; (b) disposing a second region over the first region, the second region comprising a layer of a perovskite semiconductor without open pores; and (c) disposing a third region over the second region; where: The first region is a p-type region including at least one p-type layer, and the third region is an n-type region including at least one n-type layer, the first region being disposed over the first electrode.

[0373] Typically, the first electrode comprises a transparent or semi-transparent material. Typically, the first electrode comprises a transparent conductive oxide, such as FTO, ITO or AZO. Preferably, the first electrode comprises FTO. The first electrode can be disposed on a glass substrate.

[0374] Each of the steps in the process for manufacturing an inverted optoelectronic device may be as defined elsewhere herein for the process according to the invention for manufacturing an optoelectronic device. Each of the components used or present in the process may be as defined for the optoelectronic device according to the invention.

[0375] The first region, which is a p-type region, can be as defined elsewhere herein for a p-type region. In many cases, the first region comprises a layer of PEDOT:PSS. Crosslinking can be performed to insolubilize the p-type region, so that it does not dissolve even partially during deposition of the second region, even if the deposition process would dissolve the p-type layer. Sometimes, therefore, the layer of PEDOT:PSS comprises crosslinked PEDOT:PSS. Crosslinking can be performed using a Lewis acid, such as Fe 3+ or Mg 2+ For example, (a) can be carried out using a metal cation such as (i) providing a first region comprising a layer of PEDOT:PSS; and (ii) FeCl to produce a layer of PEDOT:PSS containing crosslinked PEDOT:PSS 3treating the layer with an aqueous solution; may include.

[0376] The second region, which is an n-type region, can be as defined elsewhere herein for an n-type region. Often, the n-type region comprises a dense layer of an inorganic n-type semiconductor, such as those defined herein. Typically, the n-type region comprises a dense layer of titanium dioxide. In some embodiments, the n-type region further comprises a layer of

[60] PCBM.

[0377] Thus, in some embodiments, (c) is (i) disposing a layer of

[60] PCBM over a second region; and (ii) depositing a dense layer of titanium dioxide on top of a layer of

[60] PCBM; Includes.

[0378] In an inverted device, the second electrode can be disposed on top of the third region, which is an n-type region. Thus, the process is (d) disposing a second electrode over the third region; It may further include:

[0379] The second electrode can be disposed directly on the third region, or there may be further inverted layers. Typically, the second electrode contacts the third region. The second electrode can be as defined elsewhere herein, and typically comprises a metal. For example, the second electrode can comprise aluminum, gold, silver, nickel, palladium or platinum, typically aluminum, silver or gold. In one embodiment, the second electrode comprises silver, gold or aluminum. For example, if the n-type region comprises a dense layer of titanium and a layer of

[60] PCBM, the second electrode can comprise aluminum. The second electrode is typically disposed by vacuum deposition, although it can be deposited by any technique, such as those described herein. Thus, the second electrode can be disposed by vacuum deposition. Alternatively, the process of the present invention for manufacturing an optoelectronic device can be a process for manufacturing a tandem junction or multi-junction optoelectronic device, which comprises: (d) disposing a tunnel junction over the third region; (e) disposing a further photoactive region above the tunnel junction, which may be the same as or different from the photoactive region defined herein above; (f) optionally repeating steps (d) and (e); and (g) disposing a second electrode over the further photoactive region disposed in the previous step; Further includes:

[0380] In a process for manufacturing a tandem junction or multijunction device according to the invention, the further photoactive region may be as defined elsewhere herein before for a tandem optoelectronic device according to the invention. In particular, the further photoactive region may comprise a layer of crystalline silicon, or may comprise a thin film of CIGS, CIS or CZTSSe.

[0381] In a preferred embodiment of the process of the present invention for manufacturing optoelectronic devices, the entire process is carried out at one or more temperatures not exceeding 150°C.

[0382] In the inventive process for manufacturing an optoelectronic device, the optoelectronic device may be as further defined herein above with respect to the inventive optoelectronic device.

[0383] The invention further provides an optoelectronic device obtainable by the inventive process for manufacturing an optoelectronic device.

[0384] The invention is further illustrated in the following examples.

[0385] Real-life examples Experimental methods for element preparation Al with polymer binder 2 O 3 Preparing the paste An aluminum oxide dispersion was purchased from Sigma-Aldrich (10 wt % in water) and washed in the following manner: the dispersion was centrifuged at 7500 rpm for 6 hours and redispersed in absolute ethanol (Fisher Chemicals) using an ultrasonic probe operated at a cycle of 2 seconds on, 2 seconds off for a total sonication time of 5 minutes. This process was repeated three times.

[0386] 10 g of the original dispersion (total weight 1 g of Al 2 O 3 For each 100 mL of 10 ...

[0387] TiO with polymer binder 2 Preparing the paste Titanium dioxide dispersion containing a polymeric binder (DSL 18NR-T) was purchased from Dyesol. The dispersion was diluted with anhydrous ethanol (Fisher Chemicals):DSL 18NR-T in a 3:1 weight ratio using an ultrasonic probe; the ultrasonic probe was operated at a 2 second on, 2 second off cycle for a total sonication time of 5 minutes.

[0388] Al without polymer binder 2 O 3 Preparing the paste Aluminum oxide dispersion was purchased from Sigma-Aldrich (20% by weight in isopropanol) and was diluted to 16 volume equivalents of isopropanol.

[0389] TiO without polymer binder 2 Preparing the paste Titanium dioxide powder (P25) was purchased from (Degussa) and dispersed in ethanol at 20 mg / ml, which was diluted to 16 volume equivalents of ethanol.

[0390] Preparation of methylammonium iodide precursor and perovskite precursor solutions 33 wt% methylamine (CH) in absolute ethanol (Sigma-Aldrich) 3 NH 2 A solution of methylamine (CHNH) was reacted with 57% by weight hydroiodic acid in water (Sigma-Aldrich) in a 1:1 molar ratio in absolute ethanol 200 proof (Sigma-Aldrich) under a nitrogen atmosphere. Typical amounts were 24 ml of methylamine, 10 ml of hydroiodic acid, and 100 ml of ethanol. 3 Crystallization of I) was obtained using a rotary evaporator, forming a white precipitate indicating good crystallization.

[0391] To change the subsequent perovskite properties, methylamine can be replaced with other amines such as ethylamine, n-butylamine, tertiary butylamine, octylamine, etc. Additionally, hydroiodic acid can be replaced with other acids such as hydrochloric acid to form different perovskites.

[0392] To prepare the precursor solution, methylammonium iodide (CHNH 3 I) The precipitate and lead(II) chloride (Sigma-Aldrich) were dissolved in dimethylformamide (C 3 H 7 NO) (Sigma-Aldrich) at 30% by volume in a 1:1 molar ratio.

[0393] Cleaning and etching of the substrate and transparent electrodes Fluorine-doped tin oxide (F:SnO 2 A glass sheet (TEC 15, 15Ω / square, Pilkington USA) coated with ZnO (Teflon-Tetra-Oxide / FTO) was etched with zinc powder and HCl (2M) to give the required electrode pattern. The sheet was then washed with detergent (2% Hellmanex in water), deionized water, acetone, ethanol and finally treated under oxygen plasma for 5 min to remove all organic residues.

[0394] Dense TiO 2 Layer Deposition The patterned FTO sheets were then coated with TiO by spin-coating a weakly acidic titanium isopropoxide (Sigma-Aldrich) sol in ethanol. 2 The substrate was coated with a dense layer of 0.71:4 titanium isopropoxide:absolute ethanol in a weight ratio of 0.07:4 with an acidic solution of 2M HCl:absolute ethanol in a weight ratio of 0.07:4. After spin coating (speed=2000 rpm, acceleration=2000 rpm / s, time=60 s), the substrate was dried at 150° C. on a hotplate for 10 minutes. The optional dense layer was then heated to 500° C. on a hotplate for 30 minutes in air.

[0395] Deposition of thin mesoporous metal oxide layers Insulating metal oxide paste (e.g., Al 2 O 3 The paste) was applied on top of the dense metal oxide layer by screen printing, doctor blade coating or spin coating via appropriate mesh, doctor blade height or spin speed to produce a film with a thickness of about 100 nm. The film was then either heated to 500°C to decompose and remove the polymer binder and held there for 30 minutes (high temperature sintering), or in the absence of binder, heated to 120°C and held there for 90 minutes (low temperature sintering). The substrate was then cooled in preparation for perovskite solution deposition.

[0396] Solution deposition of perovskite precursors and formation of semiconducting perovskite thin films Dimethylformamide (IOD) with a volume concentration of 30% (methylammonium lead(II) chloride (CH 3 NH 3 PbCl 2 40 μl of the perovskite precursor solution in I)) was dispensed onto each prepared mesoporous electrode film and spin-coated at 1500 rpm for 60 s in an inert nitrogen environment. Before cooling, the coated film was placed on a hotplate set at 100° C. and left in nitrogen for 60 min. During the drying procedure at 100° C., the coated electrode changed color from light yellow to dark brown, indicating the formation of the desired perovskite film with semiconducting properties.

[0397] Evaporative deposition of perovskite precursors and formation of semiconducting perovskite thin films 1:1 molar ratio of PbI 2 and C.H. 3 NH 3Cl was ground using a pestle and mortar for 15 minutes to form bulk perovskite powder. This formed a powder that was dried in a nitrogen environment for >12 hours (>12 hours). The crucible of perovskite powder was transferred to an evaporation chamber where a vacuum was then drawn. The crucible was slowly heated to 300 °C. Once the source temperature reached 100 °C, the shutter was opened to begin deposition on the substrate. The heater was periodically switched off to allow 10 minutes of heating in the chamber. -2 Pa(10 -4 A pressure of 1000 psi (1000 mbar) was maintained. Deposition was continued until a thin film of approximately 100-300 nm was deposited onto the substrate. Following deposition, the substrate with the deposited material was heated to 50° C. for 1 hour in a nitrogen environment.

[0398] Preparation of perovskites containing formamidinium cations As an alternative to the ammonium ion, formamidinium cations can be used. Formamidinium iodide (FOI) and formamidinium bromide (FOBr) were synthesized by reacting a 0.5M molar solution of formamidinium acetate in ethanol with a 3x molar excess of hydroiodic acid (for FOI) or hydrobromic acid (for FOBr). The acid was added dropwise with stirring at room temperature, then stirring was continued for another 10 minutes. Upon drying at 100°C, a yellow-white powder was formed, which was then dried overnight in a vacuum oven before use. FOPbI 3 and FOPbBr 3 To form the precursor solution, FOI and PbI 2 or FOBr and PbBr 2 and were dissolved in anhydrous N,N-dimethylformamide in a 1:1 molar ratio at 0.88 mmol each per ml to yield a 0.88 M perovskite precursor solution. 3z Br 3(1-z) To form the perovskite precursor, the mixture was mixed with FOPbI in the required ratio. 3 and FOPbBr 3Made from a 0.88 M solution, where z ranges from 0 to 1. Films for characterization or device fabrication were spin-coated in a nitrogen-filled glove box and annealed at 170° C. for 25 min in nitrogen atmosphere.

[0399] Hole transporter deposition and device fabrication The hole transport material used was 2,2(,7,7(-tetrakis-(N,N-dimethoxyphenylamine)9,9(-spirobifluorene)) (spiro-OMeTAD, Lumtec, Taiwan), which was dissolved in chlorobenzene at a typical concentration of 180 mg / ml. Tertiary butylpyridine (tBP) was added directly to the solution at a volume-to-mass ratio of tBP:spiro-OMeTAD of 1:26 μl / mg. Lithium Bis(trifluoromethylsulfonyl)amine salt (Li-TFSI) ionic dopant was pre-dissolved in acetonitrile at 170 mg / ml and then added to the hole transporter solution at 1:12 μl / mg of Li-TFSI solution:spiro-OMeTAD. A small amount (80 μl) of the spiro-OMeTAD solution was dispensed onto each perovskite-coated film and spin-coated at 1500 rpm for 30 s in air. The films were then placed in a thermal evaporation apparatus where a 200 nm thick silver electrode was deposited on the film in high vacuum (10 -4 Pa(10 -6 Deposition was performed through a shadow mask at 1000 nm (mBar).

[0400] Modifications of the elements examined A general schematic of the device structure is shown in Figure 1a. The device can be placed on any solid substrate material (glass, plastic, metal foil, metal mesh, etc.). In Figure 1a, at least one of the metal electrodes must be transparent / semi-transparent (for example: doped or undoped metal oxide, perovskite, polymer, thin metal, metal mesh, etc.), whereas the opposite electrode can be transparent / semi-transparent or reflective. A light-absorbing perovskite, which can be n-type, p-type or intrinsic, is sandwiched between one n-type and one p-type semi-conducting layer (organic, inorganic, amorphous Si, perovskite, hybrid organic / inorganic, etc.) for selective electron and hole extraction, respectively. The structure shown can be inverted. Multijunction cells can be fabricated by stacking repeating structures.

[0401] Certain embodiments of the device of the present invention have the specific structure shown in Figure 1b. When used, a thin metal oxide layer is generally permeable to the solution-processed perovskite, ensuring direct contact of the perovskite with the electron-selective contact. Each of the preparation variations discussed here is summarized in Table 1.

[0402] [Table 1]

[0403] Results and Discussion Mesoporous Al sintered at low temperature 2 O 3 Porosity control By mixing two solvents with different viscosities and different evaporation rates in nanoparticle dispersions, Al 2 O 3 After deposition and solvent removal from the dispersion, it is possible to control the porosity of the mesoporous layer of Al. 2 O 3The refractive index of mesoporous synthetic thin films of and air depends on the volume fraction of the two components, i.e., the porosity. The refractive indexes of films formed by spin-coating dispersions with variable contents of terpineol and t-butanol onto glass slides, expressed as volume equivalents, are shown in Table 2 below. A lower refractive index indicates a larger volume fraction of air, i.e., a more porous film. In general, it was found that the addition of a co-solvent increases the porosity of the resulting mesoporous film.

[0404] [Table 2]

[0405] X-ray diffraction XRD patterns of perovskite thin films based on the different underlayer modifications investigated are shown in Figure 2a. All samples were prepared on plain glass, where we identify a thin mesoporous oxide without a dense layer. Two 110 and 220 perovskite peaks are prominent, consistent with our previous demonstration of this perovskite [Lee et al., Science, Submitted 2012]. Figure 2b shows the XRD pattern of the as-deposited perovskite. The peaks corresponding to the mixed halide perovskite are distinct from the PbI 2 This is in addition to the peaks arising from

[0406] UV-visible spectroscopy The UV-visible patterns for perovskite thin films based on the different underlayer modifications investigated are shown in Figure 3. All samples were prepared on plain glass, where we specify a thin mesoporous oxide without a dense layer. The spectra are expressed as normalized absorbance (ε = log 10 [I 0 / I 1 All spectra showed an absorption peak at wavelengths of ~800 nm, confirming the presence of perovskite. 2Although an XRD diffraction peak corresponding to is observed for the deposition-associated perovskite, the UV-visible spectrum indicates that most of the light is absorbed by the perovskite. The shape of the spectrum is consistent with our previous demonstration of this perovskite [Lee et al., Science, Submitted 2012].

[0407] Current-Voltage Characteristics The current density-voltage (JV) characteristics of several devices representative of each of the variants investigated are shown in Figure 4. A summary of the parameters extracted from these results is given in Table 3. The thickness of the as-produced thin oxide layer (t mesoporous ) and the thickness of the perovskite capping layer (t perovskite cap ) are also shown in Table 3. For the thickness measurements, the samples were prepared on plain glass, where a thin mesoporous oxide without a dense layer was identified. These thickness ratios suggest that most of the light absorption would occur within the capping layer, which forms a planar heterojunction with the hole transport material.

[0408] [Table 3]

[0409] Scanning electron microscope observation SEM micrographs of the solar cell cross-section are shown in Figures 5(a) to 5(f). The separate layers shown in the cross-section are, from right to left: glass, FTO, dense layer, mesoporous layer, perovskite capping layer, spiro-OMeTAD, and silver. Planar images of the mesoporous layer are shown in Figures 6(a) to 6(f) and Figures 7(a) and 7(b). 2 O 3 However, when using both with and without binder, and when sintering at both high and low temperatures, the images clearly show that the mesoporous structure allows for infiltration and seeding of the perovskite. The dense layers shown in Figures 6(e) and 6(f) appear featureless at the instrumental resolution. TiO 2With the binder, the film appears mesoporous, however, without the binder, the nanoparticles aggregate and form submonolayers.

[0410] conclusion The examples show that it is possible to make optoelectronic devices with a planar n-type / perovskite absorber / p-type structure. Growth of perovskite absorbers was achieved on thin scaffolds or without a scaffold from solution deposition. Devices incorporating thin seed layers can be processed at temperatures never exceeding 150° C., which is important for versatile and / or tandem / multi-junction devices. In addition, it has been shown that perovskites can be formed by deposition from bulk powders.

[0411] Inverted heterojunction perovskite solar cells Substrate preparation Fluorine-doped tin oxide (FTO) coated glass sheets (7 Ω / square Pilkington) were etched with zinc powder and HCl (2M) to obtain the required electrode pattern. The sheets were then washed with detergent (2% Hellmanex in water), deionized water, acetone, methanol, and finally treated under oxygen plasma for 5 min to remove the last traces of organic residues.

[0412] TiO x Planar membrane precursor solution: TiO x The planar membrane precursor solution consists of 0.23 M titanium isopropoxide (Sigma Aldrich, 99.999%) and 0.013 M HCl solution in ethanol (>99.9% Fisher Chemicals). To prepare this solution, titanium isopropoxide was diluted in ethanol to 0.46 M. Separately, 2 M HCl solution was diluted with ethanol to achieve a concentration of 0.026 M. Finally, the acidic solution was added dropwise to the titanium precursor solution under vigorous stirring.

[0413] Normal architecture manufacturing: The etched FTO substrate was then cooled to 300°C for 60 s at 2,000 rpm using a TiO x TiO deposited by spin-coating the planar film precursor solution and subsequently heating at 500 °C for 30 min. 2 The titanium dioxide was then coated with a dense layer of Al in isopropanol to form stoichiometric anatase titania. 2 O 3 Mesoporous scaffolds were deposited by spin-coating a colloidal dispersion of nanoparticles, followed by drying at 150 °C for 10 min. After cooling to room temperature, methylammonium iodide and PbCl 2 The perovskite was deposited by spin-coating from a DMF solution (3:1 molar ratio) of 1,2-difluorophenylamine (DMF) and 1,2-difluorophenylamine (DMF), which formed the perovskite after heating to 100 °C for 45 min. The hole transport layer was deposited by spin-coating 7 vol.% spiro-OMeTAD (2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine) 9,9'-spirobifluorene) in chlorobenzene solution with added 80 mM tertiary butylpyridine (tBP) and 25 mM lithium bis(trifluoromethanesulfonyl)imide (LITFSI) at 1000 rpm for 45 s. Finally, the device was completed by high vacuum deposition of Ag contact electrodes through a shadow mask.

[0414] Inverted Architecture Manufacturing: PEDOT:PSS: Etched FTO substrates were coated with a thin film of PEDOT:PSS deposited by spin-coating a 25:75 vol.% solution of PEDOT:PSS (Clevios):isopropanol (>99.9%, Fisher Chemicals) at 2000 rpm for 60 s, followed by annealing at 150 °C for 20 min or in 0.25 M FeCl 3 Crosslinking was achieved by immersing the substrates in the aqueous solution for 5 min, after which they were washed in two successive baths of deionized water and finally dried with nitrogen.

[0415] NiO: The spin-coating precursor for NiO thin films was prepared by dissolving nickel acetate tetrahydrate and monomethanolamine, both at 0.1 M concentration, in ethanol in a sealed vial with stirring in air on a hot plate at 70° C. for 4 h. The solution was homogenous and appeared deep green.

[0416] V 2 O 5 : Vanadium(V) was deposited by spin-coating a 1:35 vol.% solution of vanadium(V) oxytriisopropoxide (Sigma Aldrich) in isopropanol. 2 O 5 was used to coat an etched FTO substrate and then heated to 500 °C to obtain a crystalline vanadium oxide layer.

[0417] Perovskite and n-contact deposition: After cooling / drying, the perovskite precursor solution was spin-coated at 2000 rpm for 20 s, which was then heated to 100 °C for 45 min to form the structure. 20 mg mL of

[60] PCBM in chlorobenzene (anhydrous, Sigma Aldrich) -1 Electron-selective contacts were deposited by spin-coating the solution at 1000 rpm for 45 s. TiO x The planar film precursor solution was then spin-coated at 3000 rpm for 60 s, and the film was annealed at 130 °C for 10 min. Finally, the device was completed by high vacuum deposition of Al contact electrodes through a shadow mask.

[0418] Results and Discussion Perovskite-based thin-film photovoltaics have recently been reported, with an architecture developed from solid-state dye-sensitized solar cells, which collect holes via a metal cathode and electrons via a FTO anode (Ball, JM; Lee, MM; Hey, A.; Snaith, H. Low-Temperature Processed Mesosuperstructured to Thin-Film Perovskite Solar Cells, Energy & Environmental Science 2013). In this configuration, a thin layer of mesoporous alumina is layered over a dense TiO 2 A hole-selective contact is then deposited over a covered FTO substrate, followed by deposition over the organic hole transporter structure. However, this configuration has limited application in tandem solar cells, as holes are collected via the top metal cathode, and immediate improvements can be realized by using "wide bandgap" perovskites with small bandgap inorganic bottom cells (Beiley, ZM; McGehee, MD Modeling low cost hybrid tandem photovoltaics with the potential for efficiencies exceeding 20%, Energy & Environmental Science 2012, 5, 9173-9179), which are typically fabricated in a "substrate" configuration where electrons are collected at the top metal contact.

[0419] Typical materials used in organic photovoltaics as hole-selective contacts for the blends are PEDOT:PSS, V 2 O 5 and NiO, whereas PC 60BM and more recently poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) are used as electron acceptors. To determine whether these materials will work in finished devices, a good first step to check whether charge transfer to these interlayers is possible, as is becoming routine in all organic solar cells, is to measure the steady-state PL quenching efficiency. The data are shown in Figure 9 and the results are summarized in Table 4. It can be clearly seen that all the p-type layers selected in this study quench the perovskite PL even more efficiently than the model spiro-OMeTAD system, with a quenching efficiency of 99.87% for PEDOT:PSS and V 2 O 5 All n-type layers have similar values ​​for . All n-type layers have model TiO, which shows only 45% steady-state quenching efficiency. 2 Since the solar cells fabricated with a PFN interlayer yielded extremely poor photovoltaic performance, all cells fabricated in this study were fabricated with a spin-coated PC as the n-type contact. 60 Use the BM layer.

[0420] [Table 4]

[0421] PEDOT:PSS as p-type contact The first example of an inverted architecture using perovskites as both light absorbers and charge transporters uses a thin PEDOT:PSS layer as the p-contact and a PC layer as the n-contact. 60 BM and dense TiO x To enable processing of these structures in air, a TiO xA top intermediate layer of PEDOT:PSS was necessary to achieve good contact with the top Al anode. A cross-sectional SEM image of the optimized structure is shown in Figure 10. Uniform coverage of the perovskite structure is essential for fabricating optimal photovoltaic devices and is strongly influenced by the substrate on which the device is fabricated. As shown in Figures 11b) and 11d), macrocrystals over 30 μm long of perovskite are formed when assembled on top of the annealed PEDOT:PSS underlayer. Although this should be advantageous for charge transport through the layer, rather large micron-sized gaps exist between the crystals, which leads to a PC structure that is not advantageous for device performance. 60 This allows direct contact between the BM and the PEDOT:PSS underlayer. PEDOT:PSS is soluble in DMF and for this reason, 0.25 M FeCl was added to avoid redissolution of the layer when depositing the perovskite precursor in DMF. 3 PEDOT:PSS is crosslinked by immersion in an aqueous solution. Upon crosslinking PEDOT:PSS, surprisingly, the resulting perovskite film coverage increases significantly, although the average crystallite size / feature size for this material decreases considerably. The resulting coverage and crystallite size are shown in Figures 11a) and 11c) and were estimated directly from SEM images and found to be 80±1% for the annealed PEDOT:PSS film and 97±1% for the crosslinked film.

[0422] Comparing the performance of the resulting devices, we found that the device processed on cross-linked PEDOT:PSS exhibits an open circuit voltage of around 0.8 V, while the device on annealed PEDOT:PSS only achieves about 0.64 V, as shown in Figure 12a). This is consistent with a reduction in charge recombination between the charges in the PCBM layer and those in the PEDOT:PSS layer due to the improved perovskite film coverage. The device employing cross-linked PEDOT:PSS achieved an open circuit voltage of 17.2 mA cm -2 compared to the annealed PEDOT:PSS device which shows 16.2 mA cm -2Although the results show a slightly reduced short-circuit current of 1.0 V, the difference is small and within the experimental variation. Finally, the power conversion efficiency of the optimized device reaches a value of over 6.7%, significantly outperforming the performance of the annealed PEDOT:PSS device, which reaches 5.6%.

[0423] V as p-type contact 2 O 5 and NiO V 2 O 5 Both FTO and NiO are common p-type materials currently used for efficient and stable organic photovoltaic devices. Here, the inventors fabricated devices by spin-coating of appropriate precursor solutions onto FTO, with a subsequent sintering step at 500 °C to ensure a perfectly crystalline metal oxide layer. As can be seen in the SEM image in Figure 13, the surface coverage of the perovskite solution may be an issue with this material.

[0424] The photovoltaic performance of a device incorporating these layers is shown in FIG.

[0425] Comparison with normal architecture Finally, PEDOT:PSS was used as the hole-accepting layer and PC as the electron-extracting layer. 60 The Champion inverted element incorporating the BM was fabricated using the TiO 2 Comparisons are made against a conventional architecture device constructed with spiro-OMeTAD as the electron-accepting layer and hole-transporting layer. Both schemes provide 17.5 mAcm -2 The device achieves an astonishing short circuit current of over 1000 mA and a high open circuit voltage of over 0.9 V. The main difference in the power conversion efficiency of 11.8% for the conventional architecture and 7.54% for the inverted device is the lower fill factor of the latter. This is probably due to either leakage issues or series resistance losses between the PEDOT:PSS and PCBM as shown in Figure 5.a. The TiO x This is probably due to the need to use an overlayer.

[0426] The devices shown and disclosed herein offer a completely new approach to designing architectures, especially since the materials used are currently commonly available and mass produced for the organic photovoltaic industry and should therefore greatly speed up the development of mass-manufacturable systems.

[0427] conclusion Inverted device structures, in which holes are collected via FTO, are necessary for tandem applications using inorganic photovoltaic bottom cells. Here we demonstrate low-temperature, ambient air- and solution-processable photovoltaic cells based on semiconducting perovskite absorbers and selective n- and p-type contacts in the form of PEDOT:PSS and

[60] PCBM. Power conversion efficiencies of 7.5% were achieved for these inverted structures. In a sense, this demonstrates the versatility of perovskite thin-film technology for a wide range of possible device configurations, and equally importantly, it removes all obstacles to the application of perovskite technology by the organic photovoltaic community.

[0428] Two-source vapor deposition Substrate preparation The substrate preparation process was carried out in air. Fluorine-doped tin oxide (FTO) coated glass was patterned by etching with Zn metal powder and 2M HCl diluted in Milli-Q water, then cleaned with a 2% solution of Helmanex diluted in Milli-Q water, rinsed with Milli-Q water, acetone and ethanol, and dried with clean dry air. It was then treated with oxygen plasma for 10 min. TiO 2 A dense layer of was spin-coated from an acidic solution of titanium isopropoxide in ethanol and then sintered at 150° C. for 10 minutes and then at 500° C. for 30 minutes.

[0429] Vapor Deposition The system used is a dual-source deposition technique that manages the organic and inorganic sources separately. The deposition apparatus was a Kurt J. Lesker Mini Spectros Deposition System (Fig. 18) with a ceramic crucible (OLED source) housed in a nitrogen-filled dry glove box. Hence, all processes are operated in an oxygen-free environment. The working chamber is designed to operate under a pressure of 5E-4 Pa (5E-6 mbar) where the vapor particles can travel directly to the substrate. The samples were held face down in a holder above the crucible containing the source powder. To monitor the deposition rate of each source separately without interfering with each other, two crystal sensor monitors were installed only 10 cm above the crucible. These measurements are used as feedback to adjust the heating temperature to the source chemicals. Another crystal sensor is available near the substrate holder that can be used to measure the total deposition thickness.

[0430] Tooling factor measurement Because the source-to-monitor distance was different from the source-to-substrate distance, the tooling factor (the ratio of material deposited on the sensor to material deposited on the sample) of each source was calibrated separately. 3 NH 3 The density of I is not available, so we set it to 1g / cm 3 The set values ​​and results are shown in Table 5.

[0431] [Table 5]

[0432] Organic source CH during deposition process 3 NH 3 Note that it is difficult to deposit the organic sources consistently due to instability of I, and the deposition rate can vary by + / - 20% from the set point. Physical thickness was measured with a Veeco DekTak 150 film thickness probe.

[0433] Dual-source perovskite deposition The inventors aimed to investigate "planar junction" perovskite solar cells by deposition in a dual-source deposition system. The evaporated perovskite was directly deposited on TiO without a mesoporous layer. 2 It is possible to deposit a dense layer of SiO 2 on top of the dense layer of SiO 2 (FIGS. 20b and 20c).

[0434] Organic Source CH 3 NH 3 I and inorganic source PbCl 2 Approximately 200 mg and 100 mg of ZnO were weighed and loaded into two crucibles, respectively. The samples were inserted face down into the substrate holder. Once the pressure in the chamber was evacuated to 5E-4 Pa (5E-6 mbar), the shutters of the two OLED sources were opened while the sources were heated. Once the two sources reached their set values, the holder was rotated and the substrate shutters were opened to obtain a uniform thin film.

[0435] After the deposition was completed, the color of the samples changed corresponding to the composition of the two sources. All samples were then placed on a hotplate and dried at 100 °C for 50 min to crystallize the perovskite crystals before spin-coating the hole transporter layer. Figure 21 shows the surface image of the perovskite crystals after annealing on a hotplate. In previous experiments, 7% spiro-OMeTAD in chlorobenzene solution with added tertiary butylpyridine (tBP) and lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) was used as the hole transporter and spin-coated at 2000 rpm for 45 s. Finally, the device was completed by deposition of Ag contact electrodes (Figure 20a).

[0436] Comparing the evaporated perovskite with the conventional spin-coated perovskite, the evaporated perovskite has a more uniform and flat surface with fewer holes (Figure 21). The sufficient coverage of the evaporated perovskite is due to the TiO 2The hole transport layer not only makes good contact with the dense layer but also separates it from the dense layer, which will certainly benefit the photocurrent as well as the voltage throughout the system.

[0437] Element characteristic evaluation The experiment was carried out under a constant total thickness, CH 3 NH 3 IPbCl 2 We started by varying the composition of from 4:1 to 16:1 in terms of molar ratio. Once the composition was optimized, we investigated the desired thickness under the optimized composition.

[0438] The best performance is achieved by increasing the deposition rate 3 NH 3 I at 5.3 Å / s, and PbCl 2 A power conversion efficiency of 13% was achieved by setting the flow rate at 1 Å / s for the organic source CH, which ideally should give a molar ratio of 9.3:1 when tooling factors are taken into account. However, as mentioned above, 3 NH 3 Since the deposition of I always has fluctuations, 3 NH 3 The final thickness indicated in sensor 1 for CH I was 44.4 kÅ instead of the expected 42.4 kÅ. 3 NH 3 The actual average deposition rate for I should be 5.6 Å / s rather than the set value of 5.3 Å / s. In this case, the CH 3 NH 3 IPbCl 2 A film was indeed deposited under this molar ratio, which gave a physical thickness of 230 nm as measured by a Dektac probe.

[0439] The best performance was achieved with a current of 21.47mA / cm, as shown in Figure 22. 2 The short circuit photocurrent J sc , open circuit voltage V of 1.07 volts oc , and a fill factor (FF) of 0.67, resulting in a power conversion efficiency of up to 15.36%. -2The current-voltage characteristics were measured (with a 2400 Series SourceMeter, Keithley Instruments) under artificial AM1.5G sunlight at 1000 sq. m. and the solar cell was measured at a typical 0.076 cm 2 The sample was masked with a metal aperture to define the active area and measured in a light-tight sample holder to minimize any edge effects.

[0440] To define the content in the deposited films, the XRD patterns of the deposited perovskite surface were measured and then compared with the conventional XRD patterns of spin-coated perovskite and other intrinsic chemicals as shown in Figure 23. The XRD patterns show that the deposited perovskite is a cationically unsaturated cation of CH in DMF. 3 NH 3 I and PbCl 2 It is clearly shown to be almost identical to the solution-processed perovskite film (named K330) prepared from the precursor, indicating that the evaporated perovskite has the same crystal structure as the spin-coated perovskite.

[0441] The final measurement in Figure 24 is a comparison of absorbance between 200 nm evaporated and spin-coated films. The absorbance of the two 200 nm "flat junction" evaporated perovskites has a similar absorbance shape to the 200 nm "flat junction" spin-coated perovskite, but the evaporated perovskite has much larger units of absorbance.

[0442] conclusion Here, deposition-grown hybrid inorganic-organic perovskites for planar junction solar cells with power conversion efficiencies exceeding 15% have been demonstrated using CH 3 NH 3 I and PbCl 2 It has been demonstrated by properly controlling the deposition rate of perovskite as well as the deposition thickness on the substrate. The realization of utilizing deposition techniques to fabricate perovskite solar cells overcomes the limitation of solution processing of finding suitable solutions to dissolve chemicals, thus also aiding in the commercialization of hybrid inorganic-organic solar cells.

[0443] It is generally considered advantageous to maintain the 3D crystal structure in the perovskite as opposed to making layered perovskites which inevitably have large exciton binding energies (Journal of Luminescence 60&61 (1994) 269 274). It is also advantageous to be able to tune the band gap of the perovskite. It is possible to change the band gap by changing either the metal cation or the halide, which directly affects both the electronic orbitals and the crystal structure. Alternatively, it is possible to change the crystal structure by changing the organic cation (e.g. from methylammonium to formamidinium cations). However, in order to fit within the perovskite crystal, the following geometrical conditions must be satisfied:

number

[0444] Two-step perovskite layer fabrication Substrate preparation Electrode patterns were etched onto fluorine-doped tin oxide coated glass substrates (FTO, TEC7 Pilkington Glass) using a mixture of Zn powder and 2M HCl. These were then sequentially etched in Hallmanex, deionized water, acetone, propan-2-ol, and O. 2 Cleaned in plasma.

[0445] Electron selective layer deposition TiO 2A thin (approximately 50 nm) layer of TiO acts as an electron selective layer. TiO was deposited on the substrate by spin coating (speed = 2000 rpm, acceleration = 2000 rpm / s, time = 60 s) from a filtered solution (0.45 μm PTFE filter) containing Ti-isopropoxide in ethanol with added HCl. 2 These films were heated to 500° C. for 30 minutes.

[0446] PbI 2 and PbCl 2 Evaporation of At a rate of approximately 2Å / s, approximately 10 -4 Pa(10 -6 PbI was deposited by thermal evaporation onto the substrate and through a shadow mask at a pressure of 1000 mbar. 2 and PbCl 2 The deposition temperature was 100°C for 1000 s, and 150°C for 1000 s. 2 and PbCl 2 The values ​​were approximately 270°C and 310°C.

[0447] Dip-coating and perovskite conversion For dip coating, PbI was dip-coated into a 20 mg / ml solution of methylammonium iodide in anhydrous propan-2-ol in a nitrogen-filled glove box. 2 or PbCl 2 The pre-coated substrates were immersed in 10 ...

[0448] Hole transport material deposition The hole transport material, 2,2′,7,7′-tetrakis-(N,N-di-p-methoxyphenylamine)9,9′-spirobifluorene (spiro-OMeTAD), was deposited by spin-coating (speed = 2000 rpm, acceleration = 2000 rpm / s, time = 60 s) from an 80 mM chlorobenzene solution containing 80 mol% tertiary butylpyridine (tBP) and 30 mol% lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) as additives in a nitrogen-filled glovebox.

[0449] Top electrode deposition Thermal evaporation to a thickness of 150 nm at approximately 2 Å / s (pressure approximately 6.7×10 -4 The top silver electrode was deposited at 1000 K with 1000 MPa (5 μTorr).

[0450] Evaluation of device current-voltage characteristics To measure the solar cell performance, an NREL-calibrated KG5 filtered silicon reference cell was used, achieving a maximum output of 106.5 mW / cm 2 Artificial AM1.5 sunlight was generated using a calibrated Class AAB ABET artificial solar source to give an equivalent illuminance of artificial AM1.5. The mismatch factor was calculated to be 1.065 between 300 and 900 nm, which is beyond the operating range of both the KG5 filtered silicon reference cell and the perovskite test cell. Current-voltage curves were recorded using a source meter (Keithley 2400, USA). The active area of ​​the solar cell (0.0625 cm 2 The solar cell was masked with a metal aperture that defined the photoactive layer. The current density-voltage characteristics of the device are shown in Figure 32 (PbI 2 (dashed line) and CH after dip-coating as the photoactive layer. 3 NH 3 PbI 3 (solid line)) and FIG. 33 (PbCl as a photoactive layer) 2 (dashed line) and CH after dip-coating as the photoactive layer. 3 NH 3 PbI 3-x Cl x (solid line))

[0451] X-ray diffraction A Panalytical X'Pert Pro X-ray diffractometer was used to study the silver-free elements (FTO-coated glass, TiO 2 X-ray diffraction (XRD) spectra were obtained from the SiO 2 layer (photoactive layer, spiro-OMeTAD) and the results are shown in FIG.

[0452] Scanning electron microscope observation Using a Hitachi S-4300, elements without silver electrodes (FTO-coated glass, TiO 2 Scanning electron microscopy (SEM) images were obtained from the photoactive layer (spiro-OMeTAD). The electron micrographs are shown in Figure 29 ((a) PbCl 2 and (b) CH after dip coating. 3 NH 3 PbI 3-x Cl x ), and Fig. 30 ((a) PbI 2 and (b) CH after dip coating. 3 NH 3 PbI 3 (About this)

[0453] Results and Discussion The two-step method allows the production of uniform films of perovskite using economical techniques already readily available in the glazing industry. After the initial deposition of the metal dihalide, infiltration of the metal dihalide with an organic halide can produce uniform and flat films of perovskite. Figure 31 shows (a) PbCl 2 , (b) CH 3 NH 3 PbI 3-x Cl x , (c) PbI 2 , and (d) C.H. 3 NH 3 PbI 3Figure 1 shows the x-ray diffraction spectra of thin films of 100% ZnO and 150% ZnO. After dip coating, the films from the two precursors show a decrease in the relative intensity of the peaks corresponding to the precursor lattice and a relative increase in the perovskite lattice (absence in the precursor xrd spectrum), indicating significant conversion of the precursor film to the perovskite.

[0454] Figure 29 shows, from bottom to top, the glass substrate, FTO, and TiO 2 Cross-sectional scanning electron micrographs of a device showing the electron selective layer, the photoactive layer, and spiro-OMeTAD. The photoactive layer is (a) PbCl 2 , and (b) CH after dip coating. 3 NH 3 PbI 3-x Cl x Figure 30 shows, from bottom to top, a glass substrate, FTO, and TiO 2 Cross-sectional scanning electron micrographs of a device showing the electron selective layer, the photoactive layer, and spiro-OMeTAD. The photoactive layer is (a) PbI 2 , and (b) CH after dip coating. 3 NH 3 PbI 3 In both cases, the perovskite produced by dip-coating shows relative uniformity.

[0455] The current density-voltage characteristics of the element are shown in Figures 32 and 33. In Figure 32, PbI 2 (dashed line) and deposition-coated PbI by dip-coating in a solution of methylammonium iodide in propan-2-ol. 2 CH 3 NH 3 PbI 3 The characteristics of the element (solid line) converted to PbI 2 The performance parameters for J sc =1.6mA / cm 2 , PCE=0.80%, V oc =0.97V, FF=0.57. 3 NH 3 PbI 3 The performance parameters for J sc=5.3mA / cm 2 , PCE=2.4%, V oc =0.82V, FF=0.61. In FIG. 33, PbCl 2 (dashed line) and deposition-type PbCl by dip-coating in a solution of methylammonium iodide in propan-2-ol. 2 CH 3 NH 3 PbI 3-x Cl x The current density-voltage characteristics of the element (solid line) converted to PbCl 2 The performance parameters for J sc =0.081mA / cm 2 , PCE=0.006%, V oc =0.29V, FF=0.27. 3 NH 3 PbI 3-x Cl x The performance parameters for J sc =19.0mA / cm 2 , PCE=7.0%, V oc = 0.8 V, FF = 0.49. In both cases, we have shown that viable devices can be fabricated by this two-step method.

[0456] Charge carrier diffusion length estimation For charges (either electrons or holes) generated from light absorption to be efficiently collected from a thin solid film, the lifetime of the charged species (the time it survives before recombining with an oppositely charged species) must be longer than the time it takes to diffuse across the film and flow into the electrode. The diffusion coefficient (De) and lifetime (τ e ) is the diffusion length (L D )

number

[0457] Photoluminescence (PL) quenching has been successfully used previously in organic semiconductors to determine the diffusion length of photoexcited bound electron-hole pairs (excitons). By simply fabricating a solid thin film with or without the presence of an exciton quenching layer and modeling the photoluminescence decay with a diffusion equation, it is possible to accurately determine the exciton lifetime, diffusion rate and diffusion length. A cross-sectional SEM image of a 270 nm thick mixed halide absorber layer with a top hole quenching layer of spiro-OMeTAD is shown in Figure 36.

[0458] The PL decay dynamics are modeled by calculating the number and distribution of excitations in the film, n(x,t), according to a 1-D diffusion equation (Eq. 1):

number

number

[0459] [Table 6]

[0460] Triiodide perovskite (CH 3 NH 3 PbI 3 ) and mixed halide perovskites (CH 3 NH 3 PbI 3-x Cl x ) is compared in Figure 37, which shows the structure of the PMMA-coated mixed halide organolead trihalide perovskite film CH 3 NH 3 PbI 3-x Cl x (black square) and organolead triiodide perovskite film CH 3 NH 3 PbI 3 (gray squares) show the photoluminescence decay for the lifetime τ e was estimated as the time it takes to reach 1 / e of the initial intensity.

[0461] Surprisingly, the diffusion lengths for both electrons and holes in mixed halide perovskites are greater than 1 μm, which is significantly longer than the absorption depth of 100 to 200 nm. This indicates that meso- or nanostructures with this particular perovskite absorber should not be required. Triiodide perovskite CH 3 NH 3 PbI 3The films have short diffusion lengths of around 100 nm for both electrons and holes. The large diffusion lengths of mixed halide perovskites make it possible to fabricate photovoltaic devices with layers of perovskite having thicknesses greater than 100 nm, which show excellent device properties.

[0462] method Perovskite precursor preparation: Methylamine iodide (MAI) was prepared by reacting 33 wt% methylamine (Sigma-Aldrich) in ethanol with 57 wt% hydroiodic acid (HI) in water at room temperature. HI was added dropwise with stirring. Upon drying at 100 °C, a white powder was formed, which was dried in a vacuum oven overnight and recrystallized from ethanol before use. CH 3 NH 3 PbI 3-x Cl x or CH 3 NH 3 PbI 3 To form the precursor solution, use final concentrations of 0.88 M lead chloride / lead iodide and 2.64 M methylammonium iodide to prepare MAI PbCl. 2 / PbI 2 Methylammonium iodide and either lead(II) chloride (Sigma-Aldrich) or lead(II) iodide (Sigma-Aldrich) were dissolved in anhydrous N,N-dimethylformamide (DMF) in a 3:1 molar ratio to lead(II) iodide.

[0463] Substrate preparation: Glass substrates for absorption, TA and PL measurements were successively cleaned in 2% Harmanex detergent, acetone, propan-2-ol and oxygen plasma. Devices were fabricated on fluorine-doped tin oxide (FTO)-coated glass (Pilkington, 7 Ω / square). First, the FTO was removed from the area under the anode contact by etching it with 2 M HCl and zinc powder to prevent it from shunting in contact with the measurement pin. Substrates were cleaned and plasma-etched as above. Dense TiO was deposited by spin-coating a weakly acidic solution of titanium isopropoxide in ethanol. 2 A hole blocking layer of 1000 nm was deposited and annealed at 500° C. for 30 minutes. Spin coating was performed at 2000 rpm for 60 seconds.

[0464] Perovskite deposition: To form the perovskite layers for spectroscopic measurements, non-stoichiometric precursors were spin-coated onto the substrates at 2000 rpm in air. 3 NH 3 PbI 3-x Cl x For CH, the precursor is used as is. 3 NH 3 PbI 3 For CH, the precursor was diluted in DMF with a 1:1 ratio of precursor solution to DMF. After spin coating, 3 NH 3 PbI 3-x Cl x The film was annealed at 100 °C for 45 min and then cooled to 5 °C. 3 NH 3 PbI 3was annealed at 150° C. for 15 min. The top quencher was then deposited in air via spin-coating of a chlorobenzene solution using the following conditions: 10 mg / ml poly(methyl methacrylate) (PMMA; Sigma-Aldrich) and 30 mg / ml phenyl-C61-butyric acid methyl ester (PCBM; Solenne BV), both spin-coated at 1000 rpm, and 0.46 M 2,2′,7,7′-tetrakis-(N,N-di-p-methoxyphenylamine)9,9′-spirobifluorene (spiro-OMeTAD; Borun Chemicals), spin-coated at 2000 rpm.

[0465] Characterization: A field emission scanning electron microscope (Hitachi S-4300) was used to obtain SEM images. A Veeco Dectac 150 surface profilometer was used to measure the sample thickness.

[0466] Photoluminescence measurements and fitting: Steady-state and time-resolved PL measurements were acquired using a time-correlated single photon counting (TCSPC) instrument (FluoTime 300, PicoQuant GmbH). Pulse duration of 117 ps and pulse energy of ∼30 nJ / cm were used. 2 The film samples were photoexcited using a 507 nm laser head (LDH-PC-510, PicoQuant GmbH), pulsed at frequencies between 0.3 and 10 MHz with a fluence of 100 Hz. PL was collected using a high-resolution monochromator and a hybrid photomultiplier detector assembly (PMA Hybrid 40, PicoQuant GmbH).

[0467] Parameters describing the photoluminescence dynamics in the absence of any quencher must be input to the diffusion model. The form of the stretched exponential decay function is:

number

[0468] The reduced χ obtained by varying each fitting parameter independently 2 The error in the fitting parameters was determined by examining the surface. To determine the limit at a 68% confidence level, χ R 2 (p) / χ R 2 = 1.2 cut-off value was used for each case. To facilitate the comparison of lifetimes between samples with different quenchers, τ e is defined as the time it takes for the PL intensity to decay to 1 / e of its peak intensity after excitation. The error in the accuracy of this lifetime was taken as half the range of points where the average value is within 1 standard deviation of the 1 / e line. The results of photoluminescence dynamics are shown in FIGS. 34, 35, and 37.

[0469] Diffusion modeling: 1D diffusion equation,

Equation

number

number

number

[0470] The following items will also be disclosed:

[0471] 1. A photovoltaic device comprising a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; and a semiconductor layer disposed between the n-type region and the p-type region; (a) a layer of an open pore-free perovskite semiconductor having a thickness of from 10 nm to 100 μm, the layer of open pore-free perovskite semiconductor forming a first planar heterojunction with an n-type region and a second planar heterojunction with a p-type region; or (b)(i) a first layer comprising a porous material and a perovskite semiconductor disposed within the pores of the porous material; (ii) a capping layer disposed on the first layer, the capping layer being a layer of a perovskite semiconductor without open pores, the layer of perovskite semiconductor without open pores having a thickness of from 10 nm to 100 μm, the perovskite semiconductor of the capping layer being in contact with the perovskite semiconductor in the first layer; A photovoltaic element comprising:

[0472] 2. The photovoltaic device according to item 1, wherein the thickness of the layer of the open pore-free perovskite semiconductor is from 100 nm to 100 μm.

[0473] 3. A photovoltaic device according to item 1 or 2, wherein the thickness of the layer of the open pore-free perovskite semiconductor is from 100 nm to 700 nm.

[0474] 4. The photovoltaic device according to any one of items 1 to 3, wherein the perovskite semiconductor has a three-dimensional crystal structure.

[0475] 5. A photovoltaic device according to any one of items 1 to 4, wherein the layer of the perovskite semiconductor without open pores is a layer made of the perovskite semiconductor.

[0476] 6. The photovoltaic device according to item 5, wherein the thickness of the layer of the open pore-free perovskite semiconductor is from 100 nm to 100 μm.

[0477] 7. The photovoltaic device according to item 5, wherein the layer of the open pore-free perovskite semiconductor has a thickness of from 100 nm to 700 nm.

[0478] 8. The photovoltaic element according to item 1, wherein the porous material is mesoporous.

[0479] 9. The photovoltaic element according to claim 1 or 8, wherein the porous material is a dielectric material.

[0480] 10. The photovoltaic device according to item 1 or 8, wherein the porous material is a charge transport material.

[0481] 11. A photovoltaic device described in any one of items 1 and 8 to 10, wherein the perovskite semiconductor in the first layer contacts one of the p-type region and the n-type region, and the perovskite semiconductor in the capping layer contacts the other of the p-type region and the n-type region.

[0482] 12. A photovoltaic device according to any one of items 1 and 8 to 11, wherein the perovskite semiconductor in the capping layer forms a planar heterojunction with the p-type region or the n-type region.

[0483] 13. The photovoltaic device of any one of items 1 and 8 to 12, wherein the thickness of the capping layer is greater than the thickness of the first layer.

[0484] 14. The photovoltaic device of any one of items 1 and 8 to 12, wherein the thickness of the capping layer is from 100 nm to 700 nm.

[0485] 15. The photovoltaic device according to any one of items 1 to 14, wherein the n-type region is an n-type layer.

[0486] 16. A photovoltaic device according to any one of claims 1 to 14, wherein the n-type region comprises an n-type layer and an n-type exciton blocking layer.

[0487] 17. The photovoltaic device according to item 16, wherein the n-type exciton blocking layer is disposed between the n-type layer and the layer comprising the perovskite semiconductor.

[0488] 18. The photovoltaic device according to any one of items 1 to 17, wherein the p-type region is a p-type layer.

[0489] 19. The photovoltaic device according to any one of claims 1 to 17, wherein the p-type region comprises a p-type layer and a p-type exciton blocking layer.

[0490] 20. The photovoltaic device according to item 19, wherein the p-type exciton blocking layer is disposed between the p-type layer and the layer comprising the perovskite semiconductor.

[0491] 21. The photovoltaic device according to any one of items 1 to 20, wherein the perovskite semiconductor has a band gap of 3.0 eV or less.

[0492] 22. A photovoltaic device according to any one of claims 1 to 21, wherein the perovskite comprises at least one anion selected from a halide anion or a chalcogenide anion.

[0493] 23. The photovoltaic device according to item 22, wherein the perovskite comprises a first cation, a second cation, and the at least one anion.

[0494] 24. The second cation is Sn 2+ , Pb 2+ and Cu 2+ 24. The photovoltaic device according to item 23, wherein the metal cation is selected from the group consisting of:

[0495] 25. The photovoltaic device according to item 23 or 24, wherein the first cation is an organic cation.

[0496] 26. The organic cation has the formula (R 1 R 2 R 3 R 4 N) + having R 1 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 2 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 3 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; and R 4 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; Item 26. The photovoltaic device according to item 25.

[0497] 27. The organic cation has the formula (R 5 R 6 N=CH-NR 7 R 8 ) + R 5 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R6 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 7 is hydrogen, unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl, and R 8 is hydrogen, unsubstituted or substituted C 1 ~C 20 26. The photovoltaic device according to item 25, wherein the alkyl is alkyl, or unsubstituted or substituted aryl.

[0498] 28. A photovoltaic device according to any one of items 22 to 27, wherein the perovskite is a mixed-anion perovskite comprising two or more different anions selected from halide anions and chalcogenide anions.

[0499] 29. The photovoltaic device according to item 28, wherein the perovskite is a mixed halide perovskite and the two or more different anions are two or more different halide anions.

[0500] 30. A photovoltaic device according to any one of items 1 to 29, wherein the porous material is a dielectric material having a band gap of 4.0 eV or more.

[0501] 31. A photovoltaic device according to any one of items 1 to 30, comprising a first electrode, a second electrode, and the photoactive region disposed between the first electrode and the second electrode.

[0502] 32. A semiconductor device comprising a first electrode, a second electrode, and the photoactive region disposed between the first electrode and the second electrode; the second electrode contacts the n-type region of the photoactive region and the first electrode contacts the p-type region of the photoactive region; the first electrode comprises a transparent or semi-transparent electrically conductive material; the second electrode comprises a metal; Item 32. The photovoltaic device according to any one of items 1 to 31.

[0503] 33. A tandem junction or multi-junction photovoltaic element, the element comprising a first electrode, a second electrode, and a photodiode disposed between the first electrode and the second electrode. the photoactive region; and at least one other photoactive region; 33. The photovoltaic device according to any one of items 1 to 32, comprising:

[0504] 34. A first electrode, a second electrode, and a magnetron disposed between the first electrode and the second electrode. the photoactive region; and at least one other photoactive region; Including, the at least one other photoactive region comprises at least one layer of a semiconductor material; Item 34. The photovoltaic device according to item 33.

[0505] 35. The photovoltaic device according to item 34, wherein the semiconductor material comprises a layer of crystalline silicon, copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide or copper indium selenide.

[0506] 36. The following areas are examined in the following order: I. a first electrode; II. A first photoactive region as defined in any one of items 1 to 30; III. A layer of a p-type semiconductor (A); IV. A first layer of an intrinsic semiconductor; A layer of Vp-type semiconductor (B) or a layer of n-type semiconductor (B), VI. A second layer of an intrinsic semiconductor; VII. An n-type semiconductor layer (C); VIII. A second electrode; 36. The photovoltaic device according to item 34 or 35, comprising:

[0507] 37. The following areas are examined in the following order: I. a first electrode; II. A first photoactive region as defined in any one of items 1 to 30; III. A layer of a transparent conductive oxide; IV. A layer of n-type semiconductor (D); V. A layer of copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide or copper indium selenide; VI. A second electrode; 36. The photovoltaic device according to item 34 or 35, comprising:

[0508] 38. A process for manufacturing a photovoltaic device including a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; disposed between the n-type region and the p-type region, (1) a layer of an open pore-free perovskite semiconductor having a thickness of from 10 nm to 100 μm, the layer of the open pore-free perovskite semiconductor forming a first planar heterojunction with an n-type region and a second planar heterojunction with a p-type region; or (2) a first layer including a porous material and a perovskite semiconductor disposed within the pores of the porous material; a capping layer disposed on the first layer, the capping layer being a layer of a perovskite semiconductor without open pores, the layer of perovskite semiconductor without open pores having a thickness of from 10 nm to 100 μm, the perovskite semiconductor of the capping layer being in contact with the perovskite semiconductor in the first layer; wherein the process comprises: (a) providing a first region; (b) disposing a second region over the first region, the second region comprising a layer of the perovskite semiconductor without the open pores; (c) disposing a third region over the second region; and Including, the first region is an n-type region including at least one n-type layer, and the third region is a p-type region including at least one p-type layer; or the first region is a p-type region including at least one p-type layer, and the third region is an n-type region including at least one n-type layer; process.

[0509] 39. The step (b) of disposing the second region on the first region comprises: producing a solid layer of the perovskite on the first region by vapor deposition; 39. The process according to item 38, comprising:

[0510] 40. The step of producing a solid layer of the perovskite on the first region by vapor deposition comprises: (i) exposing the first region to steam, the steam comprising the perovskite or one or more reactants for producing the perovskite; (ii) allowing deposition of the vapor onto the first region to produce a solid layer of the perovskite on the first region; 40. The process according to item 39, comprising:

[0511] 41. The process of claim 39 or 40, wherein the vapor deposition is allowed to continue until the solid layer of perovskite has a thickness of from 100 nm to 100 μm.

[0512] 42. The process of claim 38 or 41, further comprising the step of generating the vapor by evaporating the perovskite or one or more reactants for generating the perovskite.

[0513] 43. The step (b) of disposing the second region on the first region comprises: generating a solid layer of said perovskite by vapor deposition, said vapor deposition being a dual source vapor deposition; 43. The process according to any one of items 38 to 42, comprising:

[0514] 44. (i) exposing the first region to a vapor, the vapor including two reactants for producing the perovskite; (ii) allowing deposition of the vapour onto the first region to produce a solid layer of the perovskite on the first region; Including, (i) further comprises the sub-step of producing the vapor comprising two reactants for producing the perovskite by evaporating a first reactant from a first source and a second reactant from a second source; 44. The process according to any one of items 38 to 43.

[0515] 45. The process of claim 44, wherein the first reactant comprises a first compound comprising (i) a metal cation and (ii) a first anion, and the second reactant comprises a second compound comprising (i) an organic cation and (ii) a second anion.

[0516] 46. ​​The organic cation has the chemical formula (R 1 R 2 R 3 R 4 N) + having R 1 is hydrogen or unsubstituted or substituted C1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 2 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; R 3 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; and R 4 is hydrogen or unsubstituted or substituted C 1 ~C 20 alkyl, or unsubstituted or substituted aryl; Item 46. The process according to item 45.

[0517] 47. The process according to item 45 or 46, wherein the first anion and the second anion are different anions selected from a halide ion or a chalcogenide ion.

[0518] 48. The process according to any one of items 45 to 46, wherein the first anion and the second anion are different anions selected from halide anions.

[0519] 49. The first reactant is BX 2 and the second reactant comprises a second compound which is AX′; B is Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ is a cation selected from X is F - , Cl - , Br - and I - an anion selected from A is a compound represented by the chemical formula (R 5 NH 3 ) + is a cation of R 5 is hydrogen or unsubstituted or substituted C 1 ~C 20 is alkyl, X' is F - , Cl - , Br - and I - and X and X' are different anions; 49. The process according to any one of items 44 to 48.

[0520] 50. The step (b) of disposing the second region on the first region comprises: (iii) heating the solid layer of perovskite; 50. The process according to any one of items 40 to 49, further comprising:

[0521] 51. The step (b) of disposing the second region on the first region comprises: (i) exposing the first region to a vapor, the vapor comprising a first perovskite precursor compound, allowing deposition of the vapor on the first region to produce a solid layer of the first perovskite precursor compound on the first region; (ii) treating the resulting solid layer of the first perovskite precursor compound with a solution comprising a second perovskite precursor compound, thereby reacting the first perovskite precursor compound with the second perovskite precursor compound to produce the layer of the perovskite semiconductor free of open porosity; Including, the first perovskite precursor compound comprises (i) a first cation and (ii) a first anion, and the second perovskite precursor compound comprises (i) a second cation and (ii) a second anion; Item 39. The process according to item 38.

[0522] 52. The process according to item 51, wherein the first cation and anion and the second cation and anion are as defined in any one of items 45 to 48.

[0523] 53. The first perovskite precursor compound has the formula BX 2 and the second perovskite precursor compound has the formula AX′, B is Ca 2+ , Sr 2+ , Cd 2+ , Cu 2+ , Ni 2+ , Mn 2+ , Fe 2+ , Co 2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ is a cation selected from X is F - , Cl - , Br - and I - an anion selected from A is a compound represented by the chemical formula (R 5 NH 3 ) + is a cation of R 5 is hydrogen or unsubstituted or substituted C 1 ~C 20 is alkyl, X' is F - , Cl - , Br - and I - and X and X' are the same or different anions; Item 52. The process according to item 51.

[0524] 54. The step (b) of disposing the second region on the first region comprises: (i) disposing one or more precursor solutions over the first region, the one or more precursor solutions comprising the perovskite dissolved in a solvent, or one or more reactants for producing the perovskite dissolved in one or more solvents; (ii) removing the one or more solvents to produce a solid layer of the perovskite on the first region; and 39. The process according to item 38, comprising:

[0525] 55. The step (b) of disposing the second region on the first region comprises: (i) disposing a precursor solution over the first region, the precursor solution including the perovskite dissolved in a solvent; (ii) removing the solvent to produce a solid layer of the perovskite on the first region; 39. The process according to item 38, comprising:

[0526] 56. The process of claim 54 or 55, comprising spin-coating the one or more precursor solutions onto the first region to produce the solid layer of the perovskite on the first region.

[0527] 57. The process of any one of items 54 to 56, wherein the steps of disposing the one or more precursor solutions over the first region and removing the one or more solvents are performed until the solid layer of the perovskite has a thickness of 100 nm to 100 μm.

[0528] 58. The step (b) of disposing the second region on the first region comprises: (iii) heating the solid layer of perovskite; 58. The process according to any one of items 54 to 57, further comprising:

[0529] 59. The process of claim 50 or 58, wherein the step of heating the solid layer of the perovskite comprises the substep of heating the solid layer of the perovskite in an inert atmosphere.

[0530] 60. The process of any one of items 50, 58, and 59, wherein the temperature to which the solid layer of perovskite is heated does not exceed 150°C.

[0531] 61. The process of any one of items 50, 58, 59, and 60, wherein the solid layer of perovskite is heated at a temperature of from 30°C to 150°C.

[0532] 62. The photoactive region comprises: The n-type region, the p-type region, and a semiconductor layer disposed between the n-type region and the p-type region. (i) the first layer comprising a porous material and a perovskite semiconductor disposed within the pores of the porous material; (ii) a capping layer disposed on the first layer, the capping layer being the layer of a perovskite semiconductor without open pores; and Including, the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer; The process comprising: (a) providing the first region; (b) disposing the second region over the first region, the second region comprising: (i) the first layer comprising a porous material and a perovskite semiconductor disposed within the pores of the porous material; (ii) the capping layer on the first layer, the capping layer being the layer of perovskite semiconductor without open pores, the perovskite semiconductor in the capping layer being in contact with the perovskite semiconductor in the first layer; a placing step including: (c) disposing the third region over the second region; 39. The process according to item 38, comprising:

[0533] 63. The step (b) of disposing the second region on the first region comprises: (i) disposing a porous material over the first region; (ii) disposing the perovskite within pores of the porous material to produce the first layer, and further disposing the perovskite onto the first layer to produce the capping layer; 63. The process according to item 62, comprising:

[0534] 64. The process of claim 63, wherein the steps of disposing the perovskite into pores of the porous material and the steps of further disposing the perovskite onto the first layer are carried out together in a single step.

[0535] 65. The step (i) of disposing a porous material over the first region comprises: a substep of disposing a composition onto the first region, the composition comprising the porous material and a solvent; removing said solvent; 65. The process according to item 63 or 64, comprising:

[0536] 66. The process of claim 65, wherein the step (i) of disposing the porous material over the first region comprises the substeps of screen printing, doctor blading, spin coating, slot-die coating, or spray coating the composition onto the first region.

[0537] 67. The process of item 65 or 66, wherein the step (i) of disposing the porous material over the first region further comprises the substep of heating the composition.

[0538] 68. The process of claim 65, wherein the composition does not include a binder and the temperature to which the composition is heated does not exceed 150°C.

[0539] 69. The process according to any one of items 65 to 68, wherein step (ii) of disposing the perovskite into pores of the porous material to produce the first layer and further disposing the perovskite onto the first layer to produce the capping layer is carried out until the capping layer has a thickness of from 100 nm to 100 μm.

[0540] 70. Step (ii) is disposing one or more precursor solutions onto the porous material, the one or more precursor solutions comprising the perovskite dissolved in a solvent or one or more reactants for producing the perovskite dissolved in one or more solvents; removing the one or more solvents to produce a solid perovskite within the pores of the porous material and a solid capping layer of the perovskite disposed on the first layer; 70. The process according to any one of items 65 to 69, comprising:

[0541] 71. Step (ii) is a sub-step of disposing a precursor solution onto the porous material, the precursor solution including the perovskite dissolved in a solvent; removing the solvent to produce a solid perovskite within the pores of the porous material and a solid capping layer of the perovskite disposed on the first layer; 71. The process according to any one of items 65 to 70, comprising:

[0542] 72. The process of any one of items 65 to 71, comprising spin coating or slot-die coating the one or more precursor solutions onto the porous material to produce the solid perovskite within the pores of the porous material and the solid capping layer of the perovskite disposed on the first layer.

[0543] 73. Step (b) of disposing the second region on the first region comprises: (iii) heating the perovskite; 73. The process according to any one of items 65 to 72, further comprising:

[0544] 74. The process of claim 73, wherein the step of heating the perovskite comprises heating the perovskite in an inert atmosphere.

[0545] 75. The process of claim 73 or 74, wherein the temperature to which the perovskite is heated does not exceed 150°C.

[0546] 76. The process of any one of claims 73 to 75, wherein the perovskite is heated at a temperature of from 30°C to 150°C.

[0547] 77. A process for manufacturing an inverted photovoltaic device including a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; and a semiconductor layer disposed between the n-type region and the p-type region; (1) a layer of an open pore-free perovskite semiconductor having a thickness of from 10 nm to 100 μm, the layer of the open pore-free perovskite semiconductor forming a first planar heterojunction with an n-type region and a second planar heterojunction with a p-type region; or (2) a first layer comprising a porous material and a perovskite semiconductor disposed within the pores of the porous material; and a capping layer disposed on the first layer, the capping layer being a layer of a perovskite semiconductor without open pores, the layer of the perovskite semiconductor without open pores having a thickness of from 10 nm to 100 μm, the perovskite semiconductor of the capping layer being in contact with the perovskite semiconductor in the first layer; wherein the process comprises: (a) providing a first region; (b) disposing a second region on the first region, the second region comprising a layer of the perovskite semiconductor without the open pores; (c) disposing a third region over the second region; and Including, the first region is the p-type region including at least one p-type layer, and the third region is the n-type region including at least one n-type layer; the first region is disposed over a first electrode; 77. The process according to any one of items 38 to 76, which is a process

[0548] 78. The process of claim 77, wherein the first electrode comprises a transparent or semi-transparent material.

[0549] 79. A process for producing a tandem junction or multijunction photovoltaic device, comprising: (d) disposing a tunnel junction over the third region; (e) disposing a further photoactive region on said tunnel junction, said further photoactive region being the same as or different from the photoactive region defined in item 38 or 62; (f) disposing a second electrode over the further photoactive region disposed in the previous step; 77. The process according to any one of items 38 to 76, further comprising:

[0550] 80. The process according to any one of items 38 to 79, wherein the entire process is carried out at one or more temperatures not exceeding 150°C.

[0551] 81. The process of any one of items 38 to 80, wherein the photovoltaic element is as defined in any one of items 1 to 37.

Claims

1. 1. An optoelectronic device comprising a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; disposed between the n-type region and the p-type region; (i) a first layer comprising a scaffold material and a perovskite semiconductor; (ii) a capping layer disposed on the first layer, the capping layer being a layer of a perovskite semiconductor having no open pores; and Including, the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer; Optoelectronic element.

2. 2. The optoelectronic device of claim 1, wherein the scaffold material is porous and the perovskite semiconductor in the first layer is disposed within pores of the scaffold material.

3. The optoelectronic device of claim 2 , wherein the scaffold material is mesoporous.

4. An optoelectronic device according to any one of claims 1 to 3, wherein the perovskite semiconductor in the capping layer is made from the same perovskite compound as the perovskite semiconductor in the first layer.

5. The optoelectronic device according to any one of claims 1 to 4, wherein the perovskite semiconductor has a three-dimensional crystal structure.

6. The optoelectronic device according to any one of claims 1 to 5, wherein the scaffold material is a dielectric scaffold material.

7. The optoelectronic device of claim 6 , wherein the scaffold material has a band gap of 4.0 eV or greater.

8. The optoelectronic device according to any one of claims 1 to 5, wherein the scaffold material is a charge transport scaffold material.

9. The optoelectronic device of claim 8 , wherein the scaffold material is a hole-transporting (p-type) scaffold material.

10. The optoelectronic device of claim 8 , wherein the scaffold material is an electron-transporting (n-type) scaffold material.

11. 11. The optoelectronic device according to any one of claims 1 to 10, wherein the perovskite semiconductor in the first layer is in contact with one of the p-type region and the n-type region, and the perovskite semiconductor in the capping layer is in contact with the other of the p-type region and the n-type region.

12. An optoelectronic device according to any one of claims 1 to 11, wherein the perovskite semiconductor in the capping layer forms a planar heterojunction with the p-type region or the n-type region.

13. 10. An optoelectronic device according to any preceding claim, wherein the perovskite semiconductor in the capping layer is in contact with the n-type region and the perovskite semiconductor in the first layer is in contact with a p-type region.

14. An optoelectronic device according to any one of claims 1 to 9 and 13, wherein the perovskite semiconductor in the capping layer forms a planar heterojunction with the n-type region.

15. The optoelectronic device according to any one of the preceding claims, wherein the thickness of the capping layer is greater than the thickness of the first layer.

16. The optoelectronic device according to any one of the preceding claims, wherein the capping layer has a thickness of from 10 nm to 100 μm.

17. The optoelectronic device according to claim 16, wherein the capping layer has a thickness of 50 nm to 1000 nm.

18. The optoelectronic device according to any one of the preceding claims, wherein the capping layer has a thickness of 100 nm or more.

19. The optoelectronic device according to claim 18, wherein the capping layer has a thickness of 100 nm to 700 nm.

20. The optoelectronic device according to any one of the preceding claims, wherein the first layer has a thickness of from 5 nm to 1000 nm.

21. The optoelectronic device according to claim 20, wherein the first layer has a thickness of 30 nm to 200 nm.

22. 22. An optoelectronic device according to any one of the preceding claims, wherein the perovskite semiconductor comprises at least one anion selected from halide anions.

23. 23. The optoelectronic device of claim 22, wherein the perovskite semiconductor comprises a first cation, a second cation, and the at least one anion, the second cation being a metal cation.

24. 24. The optoelectronic device of claim 23, wherein the first cation is an organic cation.

25. The first cation is (H ２ N=CH-NH ２ ) ＋ 24. The optoelectronic device of claim 23, wherein:

26. The second cation is Pb ２＋ Or Sn ２＋ The optoelectronic device according to any one of claims 23 to 25,

27. 27. An optoelectronic device according to any one of claims 23 to 26, wherein the perovskite semiconductor is a mixed-anion perovskite comprising two or more different halide anions.

28. 28. The optoelectronic device of any one of claims 1 to 27, wherein the optoelectronic device is a tandem junction or multi-junction optoelectronic device, the tandem junction or multi-junction optoelectronic device comprising a first electrode and a second electrode, the photoactive region and at least one further photoactive region being disposed between the first electrode and the second electrode.

29. 1. A process for manufacturing an optoelectronic device including a photoactive region, the photoactive region comprising: an n-type region including at least one n-type layer; a p-type region including at least one p-type layer; disposed between the n-type region and the p-type region; (i) a first layer comprising a scaffold material and a perovskite semiconductor; (ii) a capping layer disposed on the first layer, the capping layer being a layer of a perovskite semiconductor having no open pores; the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer; The process comprises: (a) providing a first region; (b) disposing a second region over the first region, the second region comprising: (i) a first layer comprising a scaffold material and a perovskite semiconductor; (ii) disposing a capping layer over the first layer, the capping layer being a layer of a perovskite semiconductor having no open porosity, the perovskite semiconductor in the capping layer being in contact with the perovskite semiconductor in the first layer; (c) disposing a third region over the second region; the first region is an n-type region including at least one n-type layer and the third region is a p-type region including at least one p-type layer; or the first region is a p-type region including at least one p-type layer and the third region is an n-type region including at least one n-type layer.

30. the scaffold material is porous, the perovskite semiconductor in the first layer is disposed within pores of the scaffold material, and step (b) of disposing the second region over the first region comprises: (i) placing a scaffolding material over the first region; 30. The process of claim 29, comprising: (ii) disposing the perovskite semiconductor within pores of the scaffold material to form the first layer; and further disposing the perovskite semiconductor on the first layer to form the capping layer.

31. 31. The process of claim 30, wherein the steps of disposing the perovskite semiconductor within the pores of the scaffold material and further disposing the perovskite semiconductor on the first layer are performed together in a single step.

32. 32. The process of claim 30 or 31, wherein the steps of disposing the perovskite semiconductor within the pores of the scaffold material and further disposing the perovskite semiconductor on the first layer are performed by vapor deposition.

33. 32. The process of claim 30 or 31, wherein the steps of disposing the perovskite semiconductor within the pores of the scaffold material and further disposing the perovskite semiconductor on the first layer are performed by solution deposition.

34. The step (i) of disposing the scaffolding material over the first region comprises: placing a scaffolding composition over the first region, the scaffolding composition comprising the scaffolding material, one or more solvents, and optionally a binder; removing said one or more solvents and, when present, said binder; Optionally, heating the scaffold composition; The process according to any one of claims 30 to 33, comprising:

35. 35. The process of claim 34, wherein the scaffolding composition does not include a binder and the temperature to which the scaffolding composition is heated does not exceed 150°C.

36. The step (ii) disposing one or more precursor solutions over the scaffold material, the one or more precursor solutions comprising the perovskite semiconductor dissolved in a solvent or one or more reactants for producing the perovskite semiconductor dissolved in one or more solvents; removing the one or more solvents to produce a solid perovskite within the pores of the scaffold material to produce a solid capping layer of the perovskite semiconductor disposed over the first layer; The process of any one of claims 30, 31, and 33 to 35, comprising:

37. The step (b) of disposing the second region over the first region further comprises: (iii) heating the perovskite semiconductor. The process according to any one of claims 30 to 36, comprising:

38. 38. The process of claim 37, wherein the temperature to which the perovskite semiconductor is heated does not exceed 150°C.

39. The process of any one of claims 29 to 38, wherein the entire process is carried out at one or more temperatures not exceeding 150°C.

Images