Optoelectronic device

Abstract

To provide an optoelectronic device.SOLUTION: The optoelectronic device is a tandem-junction optoelectronic device or a multi-junction electronic device, and comprises a photoactive region which comprises: an n-type region comprising at least one n-type layer; and a p-type region comprising at least one p-type layer. A layer of a perovskite semiconductor without open porosity, is disposed between the n-type region and the p-type region.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to optoelectronic devices, and more particularly, to planar junction optoelectronic devices. The present invention also relates to a process for manufacturing such optoelectronic devices.

Background Art

[0002] Thin film photovoltaics are a promising future alternative to single crystal counterparts due to their high efficiency, comparable stability, and potentially low manufacturing costs. The most widely studied thin film materials currently under consideration for photovoltaic applications include the compound semiconductors CdTe [X. Wu, Solar Energy, vol. 77, p. 803, 2004], CuIn 1-x Ga x Se2 (CIGS) [Chirila et al., Nature Materials, vol. 10, p. 857, 2011], Cu2ZnSnS4 (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 high efficiency solar cells, are typically manufactured using costly vacuum-based depositions, although recent routes towards solution processing of CIGS and CZTS have demonstrated high efficiency devices [M. Graetzel at al., Nature, vol. 488, p. 304, 2012]. Dye-sensitized solar cells and organic solar cells with low recorded efficiencies are typically manufactured using solution-based deposition processing procedures, but suffer from insufficient long-term stability. In addition, the relatively small manufacturing availability of tellurium and indium makes 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 respect 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 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 a dye-sensitized solar cell 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 for use as solid thin films in thin-film photovoltaic cells.

Prior Art Documents

Non-Patent Literature

[0004]

Non-Patent Literature 1

Non-Patent Literature 2

Non-Patent Literature 3

Non-Patent Literature 4

Non-Patent Literature 5

Non-Patent Literature 6

Non-Patent Literature 7

Non-Patent Literature 8

Non-Patent Literature 9

Non-Patent Literature 10

Non-Patent Document 11

Non-Patent Document 12

Non-Patent Document 13

Non-Patent Document 14

Non-Patent Document 15

Non-Patent Document 16

Non-Patent Document 17

Non-Patent Document 18

Non-Patent Document 19

Non-Patent Document 20

Non-Patent Document 21

Non-Patent Document 22

Non-Patent Document 23

Non-Patent Document 24

[0005] The present invention provides an optoelectronic device having a thin film of a light - absorbing or light - emitting perovskite disposed between an n - type (electron - conducting) layer and a p - type (hole - conducting) layer. The inventors unexpectedly found that excellent device efficiency can be obtained by using a dense thin film of a photoactive perovskite, contrary to the requirements for mesoporous composites. Although an open - porous perovskite structure can typically be infiltrated with a p - type or n - type material to form a bulk - heterojunction using this material, the dense perovskite layer utilized in the present invention generally forms a planar - heterojunction with the p - type layer and / or the n - type layer.

[0006] Perovskites can be formed from elements abundant on Earth by both solution processing and vacuum processing, have a variable band structure (and thus optical and electronic properties), and can be stable under atmospheric conditions. For these reasons, the perovskites used in the optoelectronic devices of the present invention are attractive for optoelectronic device applications. The inventors have shown that photoactive perovskite films can be grown by solution deposition on a thin scaffold layer or seed layer, or even without such a scaffold. Devices incorporating a thin seed layer can be processed entirely at temperatures not exceeding 150 °C, which is important for reducing manufacturing costs, enabling processing on plastic substrates to provide flexible devices, and also enabling processing on top of other layers to enable the manufacture of tandem and multi-junction devices. Perovskite thin films can also be effectively formed by evaporation from bulk powders or by co-evaporation 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 comprising at least one n-type layer, a p-type region comprising at least one p-type layer, and a layer of perovskite semiconductor having no open porosity disposed between the n-type region and the p-type region and including.

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

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

[0010] In some embodiments, the photoactive region is the n-type region, the p-type region, and a layer of perovskite semiconductor having no open porosity 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 perovskite semiconductor without open pores, the capping layer, and comprising, 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 comprising at least one n-type layer, and a p-type region comprising at least one p-type layer, and a layer of perovskite semiconductor without open pores disposed between the n-type region and the p-type region, and comprising, the process comprising (a) providing a first region, and (b) disposing a second region on the first region, the second region comprising a layer of perovskite semiconductor without open pores, the disposing step, and (c) disposing a third region on the second region, and comprising, the first region is an n-type region comprising at least one n-type layer, the third region is a p-type region comprising at least one p-type layer, or the first region is a p-type region comprising at least one p-type layer, the third region is an n-type region comprising at least one n-type layer.

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

[0013] Alternatively, the process can be used for manufacturing an optoelectronic device other than a photovoltaic device, the optoelectronic device comprising the photoactive region. The process can be used, for example, for manufacturing a light-emitting device comprising the photoactive region.

[0014] In some embodiments of the process of the present invention, the photoactive region is disposed between the n-type region, the p-type region, and 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, and the perovskite semiconductor in the capping layer being in contact with the perovskite semiconductor in the first layer, the capping layer, including.

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

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

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

[0018] Alternatively, the optoelectronic device can be other than a photovoltaic device. The optoelectronic device can be, for example, a light-emitting device.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

Figure 24

Figure 25

Figure 26

Figure 27

Figure 28

Figure 29

Figure 30

Figure 31

Figure 32

Figure 33

Figure 34

Figure 35

Figure 36

Figure 37

DETAILED DESCRIPTION OF THE INVENTION

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

[0021] As used herein, the term "photoactive region" refers to a region within an optoelectronic device that (i) can absorb light and subsequently generate free charge carriers, or (ii) can receive both electrons and holes that can later recombine to emit light.

[0022] As used herein, the term "semiconductor" refers to a material having an electrical conductivity that is intermediate in magnitude between that of a conductor and that of an insulator. A semiconductor can be an n-type semiconductor, a p-type semiconductor, or an intrinsic semiconductor.

[0023] As used herein, the term "n-type region" refers to a region of one or more electron transport (i.e., n-type) materials. Similarly, the term "n-type layer" refers to a layer of an electron transport (i.e., n-type) material. The electron transport (i.e., n-type) material may be a single electron transport compound or elemental material, or a mixture of two or more electron transport compounds or elemental materials. The electron transport compound or elemental material may or may not be 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 transport (i.e., p-type) materials. Similarly, the term "p-type layer" refers to a layer of a hole transport (i.e., p-type) material. The hole transport (i.e., p-type) material may be a single hole transport compound or elemental material, or a mixture of two or more hole transport compounds or elemental materials. The hole transport compound or elemental material may or may not be doped with one or more dopant elements.

[0025] As used herein, the term "perovskite" refers to a material or a material comprising a layer of a material having a three-dimensional crystal structure related to the three-dimensional crystal structure of CaTiO3, where the layer has a structure related to the structure of CaTiO3. The structure of CaTiO3 can be represented by the chemical formula ABX3, where A and B are cations of different sizes and X is an anion. Within 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 typically larger than the B cation. Those skilled in the art will recognize that changing A, B, and X can deform the structure of the perovskite material from the structure adopted by CaTiO3 to a lower symmetry, distorted structure with different ionic sizes. If the material includes a layer having a structure related to the structure of CaTiO3, the symmetry will also be lower. Materials comprising layers of perovskite materials are well known. For example, the structure of a material having a K2NiF4-type structure includes layers of perovskite materials. Those skilled in the art will recognize that perovskite materials can be represented by the chemical formula [A][B][X]3, 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 dispersed 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 dispersed 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 dispersed throughout the X sites in a regular or irregular manner. The symmetry of a perovskite containing more than one A cation, more than one B cation, or more than one X cation will be lower than the symmetry of CaTiO3.

[0026] As described in the previous paragraph, the term "perovskite" as used herein refers to (a) a material having a three-dimensional crystal structure related to the crystal structure of CaTiO3, or (b) a material comprising layers of a material, where the layers have a structure related to the structure of CaTiO3. Both of these categories of perovskites can be used in the devices according to the present invention, although it may be preferable in certain situations to use perovskites of the first category, (a), i.e., perovskites having 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, includes perovskites having a two-dimensional (2D) layered structure. Perovskites having a 2D layered structure can comprise layers of perovskite unit cells separated by (intercalated) molecules, and an example of such a 2D layered perovskite is [2-(1-cyclohexenyl)ethylammonium]2PbBr4. 2D layered perovskites tend to have a high exciton binding energy, which is favorable for the generation of bound electron-hole pairs (excitons) rather than free charge carriers under photoexcitation. In order for the bound electron-hole pairs to reach a p-type or n-type contact where they can convert (ionize) and generate free charge, the bound electron-hole pairs may not be sufficiently mobile. As a result, in order to generate free charge, the exciton binding energy must be overcome, which represents an energy cost to the charge generation process and results in low voltage and low efficiency in a photovoltaic cell. In contrast, perovskites having a 3D crystal structure tend to have a much lower exciton binding energy (on the order of thermal energy), and thus it is possible to generate free carriers immediately following photoexcitation. Therefore, the perovskite semiconductors utilized in the devices and processes of the present invention are preferably perovskites of the first category, (a), i.e., perovskites having a three-dimensional crystal structure. This is particularly preferred when the optoelectronic device is a photovoltaic device.

[0027] In the layer of the perovskite semiconductor without open pores, the perovskite semiconductor used in the present invention can typically (i) absorb light and thereby generate free charge carriers, and / or (ii) emit light by receiving both charges, electrons and holes, which will recombine later to emit light. Thus, the perovskite used can typically be a light-absorbing and / or light-emitting perovskite.

[0028] As will be recognized by those skilled in the art, in the layer of the perovskite semiconductor without open pores, the perovskite semiconductor used in the present invention can be a perovskite that acts as an n-type electron transport semiconductor when photo-doped. Alternatively, it can be a perovskite that acts as a p-type hole transport semiconductor when photo-doped. Thus, the perovskite can be n-type, p-type, or an intrinsic semiconductor. In a preferred embodiment, the perovskite used is a perovskite that acts as an n-type electron transport semiconductor when photo-doped.

[0029] Typically, the perovskite semiconductor used in the present invention is a photosensitizing material, i.e., a material that can perform both light emission and charge (electron or hole) transport.

[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 inside the scaffold where there is no 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 limiting size of the pores is the size of the minimum dimension of the pores, which is called the pore width (i.e., the width of slit-shaped pores, the diameter of cylindrical or spherical pores, etc.) in cases where it is less accurate with respect to most of the phenomena in which the porous solid is involved. When comparing cylindrical pores and slit-shaped pores, the diameter of the cylindrical pores (rather than the radius of the cylindrical pores) should be used as the "pore width" to avoid misinterpretation of scale changes (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 (K. S. W. 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 (i.e., pore size) of less than 2 nm. - Mesopores have a width (i.e., pore size) from 2 nm to 50 nm. - Macropores have a width (i.e., pore size) greater than 50 nm.

[0031] The pores in the material can include "closed" pores as well as open pores. Closed pores are pores in the material that are unconnected cavities, i.e., pores that are isolated within the material and not connected to any other pores, and thus pores that are inaccessible to the fluid (e.g., a liquid such as a solution) to which the material is exposed. On the other hand, "open pores" should be accessible to such a fluid. The concepts of open pores 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 pores thus refer to a small portion of the total volume of the porous material in which an effective fluid flow can occur. This thus excludes closed pores. The term "open pores" is interchangeable with the terms "connected pores" and "effective pores", and in this field is generally simply abbreviated to "pores". (In the optoelectronic device of the present invention, the perovskite semiconductor present in the "layer of perovskite semiconductor without open pores" cannot thus be called a "porous perovskite".

[0033] The term "without open pores", as used herein, thus refers to a material in a state without effective pores.

[0034] The optoelectronic device of the present invention includes a layer of perovskite semiconductor without open pores. This layer, and the perovskite semiconductor therein, have no open pores. Thus, the perovskite semiconductor in the layer is not penetrated by either the n-type material in the n-type region or the p-type material in the p-type region, or by any n-type or p-type material. Rather, the perovskite semiconductor in the layer typically forms a planar heterojunction with the n-type region or the p-type region, or in some cases, forms a planar heterojunction with both the n-type region and the p-type region.

[0035] Also, when a layer of perovskite semiconductor without open pores is a "capping layer" disposed on a first layer including a scaffold material and a perovskite semiconductor, the capping layer and the perovskite semiconductor within the capping layer are not penetrated by any scaffold material because there are no open pores. The perovskite in the first layer, on the one 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 "penetrated" 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. As used herein, the term "non-porous" refers to a material that has no pores, i.e., no open pores and no closed pores either.

[0037] Generally, a layer of perovskite semiconductor without open pores is essentially composed of a perovskite semiconductor. A perovskite is a crystalline compound. Thus, a layer of perovskite semiconductor without open pores typically consists essentially of perovskite microcrystals. In some embodiments, the layer of perovskite semiconductor without open pores is composed of a perovskite semiconductor. Thus, typically, the layer of perovskite semiconductor without open pores is composed of perovskite microcrystals.

[0038] The layer of perovskite semiconductor without open pores generally contacts at least one of an n-type region or a p-type region.

[0039] The layer of perovskite semiconductor without open pores typically forms a planar heterojunction with an n-type region or a p-type region. Either the n-type region or the p-type region can be disposed on the layer of perovskite semiconductor without open pores. However, as described above, since the layer of perovskite semiconductor has no open pores, the n-type material or the p-type material does not penetrate into the perovskite semiconductor to form a bulk heterojunction. Rather, typically, it forms a planar heterojunction with the perovskite semiconductor. Typically, the 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 contacts both the n-type region and the p-type region. In such embodiments, there will be no separate 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 described above, since the layer of perovskite semiconductor has no open pores, in such embodiments, neither the n-type region material nor the p-type region material penetrates into the perovskite semiconductor to form a bulk heterojunction. Rather, typically, it forms a planar heterojunction with the perovskite semiconductor. Thus, the layer of perovskite semiconductor without pores can form planar heterojunctions with both the n-type region and the p-type region on both sides of the layer. Therefore, 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 device of the present invention is typically a thin film device.

[0042] Typically, the thickness of the perovskite semiconductor layer without open pores ranges from 10 nm to 100 μm. More typically, the thickness of the perovskite semiconductor layer without open pores ranges from 10 nm to 10 μm. Preferably, the thickness of the perovskite semiconductor layer without open pores ranges from 50 nm to 1000 nm, for example, from 100 nm to 700 nm. The thickness of the perovskite semiconductor layer 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 high-efficiency photovoltaic device, the absorption of the absorber / photoactive region should ideally be maximized to generate a current of optimal magnitude. As a result, when using perovskite as the absorber in a solar cell, the thickness of the perovskite layer should ideally be on the order of 300 to 600 nm in order to absorb most of the sunlight across the entire visible spectrum. In particular, in a solar cell, the use of a photoactive layer with a thickness of less than 100 nm may impede the performance of the device, so the perovskite layer should generally be thicker than the absorption depth (which is defined as the film thickness required to absorb 90% of the incident light at a given wavelength, which is typically greater than 100 nm for the perovskite material of interest when significant light absorption is required across the entire visible spectrum (400 to 800 nm)).

[0044] In contrast, an electroluminescent (light-emitting) device does not need to absorb light and is thus not restricted by the absorption depth. Moreover, in practice, the p-type contact and the n-type contact 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 from the other side regardless of the thickness of the photoactive layer (i.e., the contacts are selected to inject or collect only one type of carrier). Essentially, the charge carriers are blocked from moving out of the photoactive region, thereby being available for recombination to generate photons and thus enabling the utilization of an extremely thin photoactive region.

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

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

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

[0048] Thus, in some embodiments, the photoactive region of the device is: the n-type region, and the p-type region, and 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, and the capping layer; comprising.

[0049] The perovskite semiconductor in the capping layer contacts the perovskite semiconductor in the first layer.

[0050] 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 deposition step or vapor deposition step, so the perovskite semiconductor in the capping layer is usually made of the same perovskite compound as the perovskite semiconductor in the first layer.

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

[0052] The first layer includes the scaffold material and the perovskite semiconductor disposed on the surface of the scaffold material. As used herein, the term "scaffold material" refers to a material that includes functioning as a physical support for another material. In this case, the scaffold material functions 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 typically porous, meaning it typically has an open pore structure. Thus, the "surface" of the scaffold material here typically refers to the surface of the pores within the scaffold material. In this way, the perovskite semiconductor in the first layer is typically deposited on the surface of the pores within 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%, for example, at least 70%.

[0054] The scaffold material is typically mesoporous. As used herein, the term "mesoporous" means that the average pore size of the pores within the material is from 2 nm to 50 nm. The individual pores can be of different sizes and of any shape.

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

[0056] The scaffold material can be a charge transport scaffold material (e.g., an electron transport material such as titania, or alternatively a hole transport 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 thus excludes semiconductive materials such as titania. The term dielectric as used herein typically refers to a material having a band gap of 4.0 eV or greater. (The band gap of titania is about 3.2 eV.) One of ordinary skill in the art can readily measure the band gap of a semiconductor using well-known procedures that do not require undue experimentation. For example, the band gap of a semiconductor can be estimated by fabricating a photoelectric power diode or solar cell from the semiconductor and determining the photogeneration action spectrum. It is possible to take the monochromatic photon energy at which photocurrent begins to be generated by the diode 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 determined by recording the photogeneration action spectrum of a photoelectric power diode or solar cell fabricated 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 the scaffold material) 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. Typically, the perovskite semiconductor in the capping layer forms a planar heterojunction with the region it contacts, i.e., the p-type region 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. Usually, 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, in any way, 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. 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 usually thicker than the thickness of the first layer. Most of the photoactivity (e.g., light absorption) thus usually 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 for example, from 100 nm to 700 nm.

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

[0063] On the other hand, the thickness of the first layer is often from 5 nm to 1000 nm in many cases. More typically, the thickness of the first layer is from 5 nm to 500 nm, or for example, from 30 nm to 200 nm.

[0064] The perovskite semiconductors utilized in the present invention, in the layer of the perovskite semiconductor without open pores and, when present, in the first layer, can typically (i) absorb light, thereby generating free charge carriers, and / or (ii) emit light by receiving both electrons and holes that will later recombine to emit light.

[0065] Thus, the perovskite utilized is typically a light-absorbing and / or light-emitting perovskite.

[0066] Typically, perovskite is a light-absorbing material. Typically, a perovskite that can absorb light having wavelengths from 300 nm to 2000 nm (i.e., a perovskite that can absorb light having a wavelength anywhere within this range) is utilized. More typically, the perovskite utilized can absorb light having wavelengths within the range from 300 to 1200 nm, or, for example, can absorb light having wavelengths from 300 to 1000 nm. More typically, the perovskite utilized can absorb light having a wavelength anywhere within the range from 300 to 800 nm.

[0067] The perovskite semiconductors utilized in the optoelectronic device of the present invention preferably have a band gap narrow enough to enable the 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, because such a band gap is low enough for sunlight to excite electrons throughout the photovoltaic device. Some perovskites, including some oxide perovskites and 2D layered perovskites, have a band gap wider than 3.0 eV and are thus less preferred than perovskites having a band gap of 3.0 eV or less for use in photovoltaic devices. Such perovskites are CaTiO3, SrTiO3, and CaSrTiO3:Pr 3+including 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, 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, a halide refers to a fluoride anion, a chloride anion, a bromide anion, an iodide anion, or an astatide anion. The term "chalcogenide anion" as used herein refers to an anion of a Group 6 element, i.e., a chalcogen. Typically, a chalcogenide refers to an oxide anion, a sulfide anion, a selenide anion, or a telluride anion.

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

[0074] As will be appreciated by those skilled in the art, a perovskite can contain more cations or more anions. For example, a perovskite can contain 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 can be selected from tin, lead, and copper, preferably selected from tin and lead.

[0076] More typically, the second cation is 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+ , Sn 2+ , Yb 2+ and Eu 2+can be selected from. The second cation can be selected from Sn 2+ , Pb 2+ and Cu 2+ . Usually, the second cation is selected from Sn 2+ and Pb 2+ .

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

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

[0079] Usually, in the optoelectronic device of the present invention, the organic cation has the chemical formula (R1R2R3R4N) + , where R1 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R2 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R3 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, and R4 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl.

[0080] Alternatively, the organic cation can have the chemical formula (R5NH3) + , where R5 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl. For example, R5 can be methyl or ethyl. Typically, R5 is methyl.

[0081] In some embodiments, the organic cation has the chemical formula (R5R6N=CH-NR7R8)+ has, where R5 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; R6 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; R7 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; and R8 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl.

[0082] Typically, in the cation (R5R6N=CH-NR7R8) + R5 is hydrogen, methyl or ethyl, R6 is hydrogen, methyl or ethyl, R7 is hydrogen, methyl or ethyl, and R8 is hydrogen, methyl or ethyl. For example, R5 can be hydrogen or methyl, R6 can be hydrogen or methyl, R7 can be hydrogen or methyl, and R8 can be hydrogen or methyl.

[0083] The organic cation can have, for example, the chemical formula (H2N=CH-NH2) + can have.

[0084] As used herein, an alkyl group can be a substituted or unsubstituted, straight-chain or branched-chain saturated radical, often a substituted or unsubstituted straight-chain saturated radical, more often an unsubstituted straight-chain saturated radical. C1-C 20 The alkyl group is a substituted or unsubstituted, straight-chain or branched-chain saturated hydrocarbon radical. Typically, the alkyl group is C1-C 10Alkyl, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl, or C1-C6 alkyl, such as methyl, ethyl, propyl, butyl, pentyl or hexyl, or C1-C4 alkyl, such as methyl, ethyl, i-propyl, n-propyl, t-butyl, s-butyl or n-butyl.

[0085] When the alkyl group is a substituted type, typically, it is a substituted or unsubstituted C1-C 20 Alkyl, substituted or unsubstituted aryl (as defined herein), cyano, amino, C1-C 10 Alkylamino, di(C1-C 10 )alkylamino, allylamino, diallylamino, allylalkylamino, amide, acylamide, hydroxy, oxo, halo, carboxy, ester, acyl, acyloxy, C1-C 20 Alkoxy, aryloxy, haloalkyl, sulfonic acid, sulfhydryl (i.e., thiol, -SH), C1-C 10 Alkylthiol, allylthiol, sulfonyl, phosphoric acid, phosphate ester, phosphonic acid, and phosphonate ester, and contains one or more substituents selected therefrom. Examples of the substituted alkyl group include haloalkyl, hydroxyalkyl, aminoalkyl, alkoxyalkyl, and aralkyl groups. As used herein, the term aralkyl refers to a C1-C 20 alkyl group in which at least one hydrogen atom is replaced by an aryl group. Examples of such groups include, but are not limited to, benzyl (phenylmethyl, PhCH2-), benzhydryl (Ph2CH-), trityl (triphenylmethyl, Ph3C-), phenethyl (phenylethyl, Ph-CH2CH2-), styryl (Ph-CH=CH-), cinnamyl (Ph-CH=CH-CH2-).

[0086] Typically, the substituted alkyl group has one, two or three substituents, such as one or two.

[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 ring portion. Examples include phenyl, naphthyl, indenyl, and indanyl groups. The aryl group is unsubstituted or substituted. When the aryl group as defined above is substituted, typically C1-C6 alkyl which is unsubstituted (for forming an aralkyl group), aryl which is unsubstituted, cyano, amino, C1-C 10 alkylamino, di(C1-C 10 )alkylamino, allylamino, diallylamino, allylalkylamino, amide, acylamide, hydroxy, halo, carboxy, ester, acyl, acyloxy, C1-C 20 alkoxy, aryloxy, haloalkyl, sulfhydryl (i.e., thiol, -SH), C1-C 10It contains one or more substituents selected from alkylthiol, allylthiol, sulfonic acid, phosphoric acid, phosphate ester, phosphonic acid and phosphonate ester, and sulfonyl. Typically, an aryl group bears 0, 1, 2 or 3 substituents. The substituted aryl group can be substituted at two positions with one C1-C6 alkylene group or a bidentate group represented by the chemical formula -X-(C1-C6) alkylene or -X-(C1-C6) alkylene-X-, where X is selected from O, S and NR, and R is H, aryl, or C1-C6 alkyl. Thus, the substituted aryl group can be an aryl group fused with a cycloalkyl group or a heterocyclyl group. The ring atoms of the aryl group can include one or more heteroatoms (as in a heteroaryl group). Such an aryl group (heteroaryl group) is a substituted or unsubstituted monocyclic or bicyclic heteroaromatic group typically containing from 6 to 10 atoms in a cyclic moiety containing one or more heteroatoms. This is generally a 5-membered or 6-membered ring containing at least one heteroatom selected from O, S, N, P, Se and Si. This can contain, for example, 1, 2 or 3 heteroatoms. Examples of heteroaryl groups include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, furanyl, thienyl, pyrazolidinyl, pyrrolyl, oxazolyl, oxadiazolyl, isoxazolyl, thiadiazonyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, quinolyl, and isoquinolyl. The heteroaryl group can be unsubstituted or substituted, for example, as specified above for aryl. Typically, it bears 0, 1, 2 or 3 substituents.

[0088] Primarily, in the optoelectronic device of the present invention, in the organic cation, R1 is hydrogen, methyl or ethyl, R2 is hydrogen, methyl or ethyl, R3 is hydrogen, methyl or ethyl, and R4 is hydrogen, methyl or ethyl. For example, R1 can be hydrogen or methyl, R2 can be hydrogen or methyl, R3 can be hydrogen or methyl, and R4 can be hydrogen or methyl.

[0089] Alternatively, the organic cation can have the chemical formula (R5NH3) + wherein R5 is hydrogen or an unsubstituted or substituted C1-C 20 alkyl. For example, R5 can be methyl or ethyl. Typically, R5 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. Usually, the two or more different anions are two or more different halide anions.

[0091] Thus, the perovskite to be used can 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 can comprise two different anions, and for example, the anions can be a halide anion and a chalcogenide anion, two different halide anions, or two different chalcogenide anions. The first cation and the second cation can be as further defined hereinbefore. Thus, the first cation can be an organic cation which may also be further defined herein. For example, as defined above, a cation of the chemical formula (R1R2R3R4N) + or the chemical formula (R5NH3) + can be used. Alternatively, the organic cation can be a cation of the chemical formula [R5R6N=CH-NR7R8] as defined above + 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+ Co2+ , Pd 2+ , Ge 2+ , Sn 2+ , Pb 2+ , Yb 2+ and Eu 2+ can be selected from. Usually, the second cation is selected from Sn 2+ and Pb 2+ .

[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, these 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] In many cases, in the optoelectronic device of the present invention, the perovskite has the chemical formula (I): [A][B][X]3 (I) is a perovskite compound, where [A] is at least one organic cation, [B] is at least one metal cation, and [X] is the at least one anion.

[0094] The perovskite of chemical formula (I) can contain one, two, three or four different metal cations, typically one or two different metal cations. Also, the perovskite of chemical formula (I) can contain, for example, one, two, three or four different organic cations, typically one or two different organic cations. Similarly, the perovskite of chemical 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 compound of formula (I) can be as further defined previously herein. Thus, the organic cation can be a cation of formula (R1R2R3R4N) + and a cation of formula (R5NH3) + . The metal cation can be selected from divalent metal cations. 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+ . Usually, the metal cation is Sn 2+ or Pb 2+ .

[0096] The organic cation can be selected, for example, from cations of formula (R5R6N=CH-NR7R8) + and cations of formula (H2N=CH-NH2) + . The metal cation can be selected from divalent metal cations. 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+ . Usually, the metal cation is Sn 2+ or Pb 2+ .

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

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

[0099] Typically, [X] in Chemical 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 cation and the metal cation in the perovskite compound of Chemical Formula (IA) can be further defined as previously described herein. Thus, the organic cation can be selected from the cations of Chemical Formula (R1R2R3R4N) + and the cations of Chemical Formula (R5NH3) + as defined above. 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 Eu2+ can be selected from. Usually, the metal cation is Sn 2+ or Pb 2+ .

[0101] The organic cation can be, for example, a cation of the chemical formula (R5R6N=CH-NR7R8) as defined above, + and a cation of the chemical formula (H2N=CH-NH2) + . 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+ can be selected from. Usually, the metal cation is Sn 2+ or Pb 2+ .

[0102] Typically, in the optoelectronic device of the present invention, the perovskite is of the chemical formula (II): ABX 3-y X’ y (II) a perovskite compound, where 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 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 Chemical Formula (II), the organic cation and the metal cation can be as further defined previously herein. Thus, the organic cation can be a cation of the formula (R1R2R3R4N) + as defined above, or more typically, a cation of the formula (R5NH3) + as defined above. 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+ selected from. Usually, the metal cation is Sn 2+ or Pb 2+ .

[0105] In some embodiments, the perovskite is a perovskite compound of Chemical Formula (IIa): ABX 3z X’ 3(1-z) (IIa) wherein A is an organic cation of the formula (R5R6N=CH-NR7R8) + wherein R5 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; R6 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; R7 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; and R8 is hydrogen, unsubstituted or substituted C1-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 ranges from 0.05 to 0.95.

[0106] Typically, z ranges 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 be in the range from any one of these values to any other of these values (for example, from 0.2 to 0.7, or from 0.1 to 0.8).

[0107] B, X, and X’ can be as defined previously herein. The organic cation can be, for example, (R5R6N=CH-NR7R8) + wherein R5, R6, R7, and R8 are independently selected from hydrogen and unsubstituted or substituted C1-C6 alkyl. For example, the organic cation can be (H2N=CH-NH2) + and can be so on.

[0108] In many cases, in the optoelectronic device of the present invention, the perovskite is a perovskite compound selected from CH3NH3PbI3, CH3NH3PbBr3, CH3NH3PbCl3, CH3NH3PbF3, CH3NH3PbBrI2, CH3NH3PbBrCl2, CH3NH3PbIBr2, CH3NH3PbICl2, CH3NH3PbClBr2, CH3NH3PbI2Cl, CH3NH3SnBrI2, CH3NH3SnBrCl2, CH3NH3SnF2Br, CH3NH3SnIBr2, CH3NH3SnICl2, CH3NH3SnF2I, CH3NH3SnClBr2, CH3NH3SnI2Cl, and CH3NH3SnF2Cl.

[0109] For example, in the optoelectronic device of the present invention, the perovskite can be selected from CH3NH3PbBrI2, CH3NH3PbBrCl2, CH3NH3PbIBr2, CH3NH3PbICl2, CH3NH3PbClBr2, CH3NH3PbI2Cl, CH3NH3SnBrI2, CH3NH3SnBrCl2, CH3NH3SnF2Br, CH3NH3SnIBr2, CH3NH3SnICl2, CH3NH3SnF2I, CH3NH3SnClBr2, CH3NH3SnI2Cl, and CH3NH3SnF2Cl.

[0110] Typically, the perovskite is selected from CH3NH3PbBrI2, CH3NH3PbBrCl2, CH3NH3PbIBr2, CH3NH3PbICl2, CH3NH3PbClBr2, CH3NH3PbI2Cl, CH3NH3SnF2Br, CH3NH3SnICl2, CH3NH3SnF2I, CH3NH3SnI2Cl, and CH3NH3SnF2Cl.

[0111] More typically, the perovskite is selected from CH3NH3PbBrI2, CH3NH3PbBrCl2, CH3NH3PbIBr2, CH3NH3PbICl2, CH3NH3PbClBr2, CH3NH3PbI2Cl, CH3NH3SnF2Br, CH3NH3SnF2I, and CH3NH3SnF2Cl.

[0112] Generally, the perovskite is selected from CH3NH3PbBrI2, CH3NH3PbBrCl2, CH3NH3PbIBr2, CH3NH3PbICl2, CH3NH3SnF2Br, and CH3NH3SnF2I.

[0113] In many cases, the perovskite used is CH3NH3PbCl2I.

[0114] In some embodiments, the perovskite is (H2N=CH-NH2)PbI 3z Br 3(1-z)It can be a perovskite, where z is greater than 0 and less than 1. z can be as further defined previously in this specification.

[0115] The perovskite semiconductor used in the optoelectronic device of the present invention can contain, for example, a mixture of the mixed-anion perovskite and the single-anion perovskite. Here, the single-anion perovskite contains a first cation, a second cation, and an anion selected from halide anions and chalcogenide anions. Here, the first cation and the second cation are as defined in this specification for the mixed-anion perovskite. For example, the optoelectronic device can contain CH3NH3PbICl2 and CH3NH3PbI3; CH3NH3PbICl2 and CH3NH3PbBr3; CH3NH3PbBrCl2 and CH3NH3PbI3; or CH3NH3PbBrCl2 and CH3NH3PbBr3.

[0116] The optoelectronic device can contain a perovskite of the chemical formula (H2N=CH-NH2)PbI 3z Br 3(1-z) where z is as defined in this specification and is a single-anion perovskite such as (H2N=CH-NH2)PbI3 or (H2N=CH-NH2)PbBr3.

[0117] Alternatively, the perovskite semiconductor used in the optoelectronic device of the present invention can include more than one perovskite, where each perovskite is a mixed anion perovskite, and here, the mixed anion perovskite is as defined herein. For example, the optoelectronic device can include two or three of the perovskites. The optoelectronic device of the present invention can, for example, include two perovskites, where both perovskites are mixed anion perovskites. For example, the optoelectronic device can include CH3NH3PbICl2 and CH3NH3PbIBr2; CH3NH3PbICl2 and CH3NH3PbBrI2; CH3NH3PbBrCl2 and CH3NH3PbIBr2; or CH3NH3PbBrCl2 and CH3NH3PbIBr2.

[0118] The optoelectronic device can include two different perovskites, where each perovskite has the chemical formula (H2N=CH-NH2)PbI 3z Br 3(1-z) where z is as defined herein.

[0119] In some embodiments of the optoelectronic device of the present invention, when [B] is a single metal cation that is Pb 2+ one of the two or more different halide anions is iodide or fluoride, and when [B] is Sn 2+When it is a single metal cation, one of the two or more different halide anions is fluoride. Usually, 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 the other of the two or more different halide anions is fluoride or chloride. In many cases, 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, (a) one of the two or more different anions is fluoride, and the other 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 the other 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+ is. Alternatively, in the optoelectronic device of the present invention, the divalent metal cation can be Pb 2+ and.

[0120] The n-type region in the optoelectronic device of the present invention includes one or more n-type layers. In many cases, the n-type region is an n-type layer, that is, a single n-type layer. In another embodiment, in any way, the n-type region can include an n-type layer and an n-type exciton blocking layer. In the case where an n-type exciton blocking layer is used, the n-type exciton blocking layer is usually disposed between the n-type layer and the layer including the perovskite semiconductor.

[0121] The exciton blocking layer is a material with a wider band gap than the perovskite, and has either a conduction band or a valence band that closely matches the conduction band or valence band of the perovskite. When the conduction band (or the lowest unoccupied molecular orbital energy level) of the exciton blocking layer is closely positioned to the conduction band of the perovskite, electrons will move from the perovskite into the exciton blocking layer, pass through the exciton blocking layer, or pass through the exciton blocking layer and move back into the perovskite, and we name this the n-type exciton blocking layer. Examples of such materials are 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] The n-type layer is a layer of an electron transport (i.e., n-type) material. The n-type material can be a single n-type compound material or elemental material, or a mixture of two or more n-type compound materials or elemental materials, which may or may not be doped with one or more dopant elements.

[0123] The n-type layer used in the optoelectronic device of the present invention can include an inorganic or organic n-type material.

[0124] A suitable inorganic n-type material can 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, and any of these may or may not be doped.

[0125] The n-type material can 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, and any of these may or may not be doped.

[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 can include an inorganic material selected from oxides of titanium, tin, zinc, niobium, tantalum, tungsten, indium, gallium, neodymium, palladium, or cadmium, or oxides of a mixture of two or more of the foregoing metals. For example, the n-type layer can include TiO2, SnO2, ZnO, Nb2O5, Ta2O5, WO3, W2O5, In2O3, Ga2O3, Nd2O3, PbO, or CdO.

[0128] Other suitable n-type materials that can be used include sulfides of cadmium, tin, copper, or zinc, and sulfides of a mixture of two or more of the foregoing metals. For example, the sulfide can be FeS2, CdS, ZnS, or Cu2ZnSnS4.

[0129] The n-type layer includes, for example, selenides of cadmium, zinc, indium, or gallium, or selenides of a mixture of two or more of the foregoing metals; or tellurides of cadmium, zinc, cadmium or tin, or tellurides of a mixture of two or more of the foregoing metals. For example, the selenide can be Cu(In,Ga)Se2. Typically, the telluride is a telluride of cadmium, zinc, cadmium or tin. For example, the telluride can be CdTe.

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

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

[0132] Typically, the n-type layer includes TiO2.

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

[0134] Organic and polymeric electron transport materials, as well as other n-type materials including electrolytes, can also be utilized. Suitable examples include organic electron transport materials containing fullerenes or fullerene derivatives, perylenes or their derivatives, or poly{[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)}(P(NDI2OD-T2)), but are not limited thereto.

[0135] The p-type region in the optoelectronic device of the present invention includes 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, in any way, the p-type region can include a p-type layer and a p-type exciton blocking layer. In the case of using a p-type exciton blocking layer, the p-type exciton blocking layer is usually disposed between the p-type layer and the layer containing the perovskite semiconductor. When the valence band (or the highest occupied molecular orbital level) of the exciton blocking layer is closely located with the valence band of the perovskite, holes can proceed from the perovskite into the exciton blocking layer, pass through the exciton blocking layer, or pass through the exciton blocking layer and proceed into the perovskite, and we name this the p-type exciton blocking layer. An example of such a material 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] The p-type layer is a layer of a 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 or may not be doped with one or more dopant elements.

[0137] The p-type layer used in the optoelectronic device of the present invention can include an inorganic or organic p-type material.

[0138] A suitable p-type material can be selected from polymeric or molecular hole transporters. The p-type layer used in the optoelectronic device 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). Usually, the p-type material is selected from Spiro-OMeTAD, P3HT, PCPDTBT, and PVK. Preferably, the p-type layer used in the optoelectronic device of the present invention includes 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 containing one or more of the following components: thiophenyl, phenylene, dithiazolyl, benzothiazolyl, diketopyrrolopyrrolyl, ethoxydithiophenyl, amino, triphenylamino, carbazolyl, ethylenedioxyphenyl, dioxythiophenyl, or fluorenyl. Thus, the p-type layer used in the optoelectronic device of the present invention can contain, for example, any of the above-described molecular hole transport materials, polymers, or copolymers.

[0141] Suitable p-type materials also 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), TNATA (4,4’,4’’-tris-(N-(naphthylen-2-yl)-N-phenylamino)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 a base. The p-type layer can be doped, for example, 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 that is tBP (tertiary butylpyridine).

[0143] In addition or alternatively, the p-type layer can be doped to increase the hole concentration. To increase the hole concentration, the p-type layer can be doped, for example, with NOBF4 (nitrosonium tetrafluoroborate).

[0144] In another embodiment, the p-type layer can include an inorganic hole transporter. For example, the p-type layer can include oxides of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu2O, CuO, or CIS; perovskite; amorphous Si; 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, and these inorganic materials may or may not be doped. The p-type layer can be a dense layer of the inorganic hole transporter.

[0145] The p-type layer can include an inorganic hole transporter including, for example, oxides of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu2O, CuO, or CIS; 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, and these inorganic materials may or may not be doped. The p-type layer can include an inorganic hole transporter selected, for example, from CuI, CuBr, CuSCN, Cu2O, CuO, or CIS. The p-type layer can be a dense layer of the inorganic hole transporter.

[0146] Typically, the p-type layer includes a polymer or molecular hole transporter, and the n-type layer includes an inorganic n-type material. The p-type polymer or molecular hole transporter can be any suitable polymer or molecular hole transporter, for example, any one of those listed above. Similarly, the inorganic n-type material can be any suitable n-type inorganic, for example, any one of those listed above. In one embodiment, for example, the p-type layer includes Spiro-OMeTAD and the n-type layer includes TiO2. Typically, in that embodiment, the n-type layer containing TiO2 is a dense layer of TiO2.

[0147] In another embodiment, both the n-type layer and the p-type layer include inorganic materials. Thus, the n-type layer can include an inorganic n-type material and the p-type layer can include an inorganic p-type material. The inorganic p-type material can be any suitable p-type inorganic, for example, any one of those listed above. Similarly, the inorganic n-type material can be any suitable n-type inorganic, for example, any one of those listed above.

[0148] In yet another embodiment, the p-type layer includes an inorganic p-type material (i.e., an inorganic hole transporter), and the n-type layer includes a polymer or molecular hole transporter. The inorganic p-type material can be any suitable p-type inorganic, for example, any one of those listed above. Similarly, the n-type polymer or molecular hole transporter can be any suitable n-type polymer or molecular hole transporter, for example, any one 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,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)}(P(NDI2OD-T2)). The inorganic hole transporter can include, for example, oxides of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu2O, 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, and these inorganic materials may or may not be doped. More typically, the inorganic hole transporter includes oxides of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu2O, 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, and these inorganic materials may or may not be doped. Thus, the inorganic hole transporter can include oxides of nickel, vanadium, copper, or molybdenum; CuI, CuBr, CuSCN, Cu2O, 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 a preferred embodiment, however, neither the p-type layer nor the n-type layer includes perovskite. Thus, preferably, neither the p-type region nor the n-type region includes perovskite.)

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

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

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

[0154] The addition of different doping agents to different samples of the same material can result in 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 becoming 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 becoming a p-type material.

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

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

[0157] In some embodiments, a second perovskite that is different from the first perovskite and is utilized in a p-type layer or an n-type layer has the chemical formula (IB): [A][B][X]3(IB) wherein [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 will be recognized by those skilled in the art, [A] can include Cs + .

[0159] Typically, [B] includes Pb 2+ or Sn 2+ . More typically, [B] includes Pb 2+ .

[0160] Typically, [X] includes a halide anion or multiple different halide anions.

[0161] Typically, [X] includes I - .

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

[0163] Typically, the perovskite compound of chemical formula IB is CsPbI3 or CsSnI3. For example, the perovskite compound of chemical formula (IB) can be CsPbI3.

[0164] Alternatively, the perovskite compound of chemical formula (IB) can be CsPbI2Cl, CsPbICl2, CsPbI2F, CsPbIF2, CsPbI2Br, CsPbIBr2, CsSnI2Cl, CsSnICl2, CsSnI2F, CsSnIF2, CsSnI2Br or CsSnIBr2. For example, the perovskite compound of chemical formula (IB) can be CsPbI2Cl or CsPbICl2. Typically, the perovskite compound of chemical formula (IB) is CsPbICl2.

[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] usually contains an organic cation as defined herein as above for the first perovskite; and [B] typically contains a metal cation as defined herein. The metal cation can be defined as before herein 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 an embodiment of the optoelectronic device of the present invention including the first layer can be a dielectric scaffold material. Usually, the dielectric scaffold material has a band gap of 4.0 eV or more.

[0168] Usually, in the optoelectronic device of the present invention, the dielectric scaffold material includes an oxide of aluminum, zirconium, silicon, yttrium or ytterbium. For example, the dielectric scaffold material can include zirconium oxide, silica, alumina, ytterbium oxide or yttrium oxide, or aluminosilicate. In many cases, the dielectric scaffold material includes silica or alumina. More typically, the dielectric scaffold material includes porous alumina.

[0169] Typically, in the optoelectronic device of the present invention, the dielectric scaffold material is mesoporous. Thus, typically, in the optoelectronic device of the present invention, the dielectric scaffold material includes mesoporous alumina.

[0170] Alternatively, the scaffold material can be an inorganic electron transport material such as 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 include TiO2, SnO2, ZnO, Nb2O5, Ta2O5, WO3, W2O5, In2O3, Ga2O3, Nd2O3, PbO, or CdO. In many cases, the scaffold material can include mesoporous oxides 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 an embodiment, the scaffold material includes porous titania, preferably mesoporous titania.

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

[0172] On the other hand, the scaffold material can be an inorganic hole transport material. Thus, the scaffold material can include, for example, oxides of nickel, vanadium, copper or molybdenum, CuI, CuBr, CuSCN, Cu2O, CuO or CIS.

[0173] In an embodiment of the optoelectronic device of the present invention including the first layer, the porosity of the scaffold material is usually 50% or more. For example, the porosity can 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 typically includes a first electrode and a second electrode. Thus, the optoelectronic device of the present invention typically includes a first electrode, a second electrode, and the light-active region disposed between the first electrode and the second electrode.

[0176] The first electrode and the second electrode are an anode and a cathode, and usually, one or both of the anode and the cathode are transparent to allow light to enter. At least one of the electrodes is usually translucent from the visible region to the near-infrared region of the solar spectrum. Translucency typically means having a transparency of 80%, and it 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 comprise a transparent or translucent electrically conductive material. For example, the first electrode can comprise 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 be ITO (indium tin oxide), FTO (fluorine-doped tin oxide), or AZO (aluminum-doped tin oxide), preferably FTO. The first electrode can comprise 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 from 200 nm to 600 nm, more typically from 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 comprise FTO and can be disposed on a glass substrate. In the optoelectronic device of the present invention, since the first electrode is often transparent or translucent, light ingress and / or egress typically occurs through the first electrode. Particularly when the metal electrode forms a thin layer, light can enter the device through the metal electrode (as can often be the case for the second electrode).

[0178] In many cases, the second electrode comprises a metal. Typically, the second electrode comprises a metal with a large work function, such as aluminum, gold, silver, nickel, palladium, or platinum, typically silver or gold. Typically, the thickness of the second electrode is from 50 nm to 250 nm, more generally from 100 nm to 200 nm. For example, the thickness of the second electrode can be 150 nm.

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

[0180] Therefore, the optoelectronic device according to the present invention can include the following regions in the following order: I. A first electrode, II. An n-type region including at least one n-type layer, III. A layer of perovskite semiconductor without open pores, IV. A p-type region including at least one p-type layer, and V. A second electrode.

[0181] The term "the following regions in the following order" means, as used herein, that each of the recited regions will be present and the order of each of the indicated layers will be in the given order. 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 the space of the set of regions: I, II, III is equivalent to III, II, I (i.e., it does not define "up" and "down" or "left" and "right"). Additional layers or regions can be shown between each of these regions. For example, I, II, III can include 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, in any way, each of the regions I to V contacts both the preceding region and the following region. Each of the regions (the first electrode, the n-type region, the layer of perovskite semiconductor without open pores, the p-type region and the second electrode) can be made as defined somewhere in this specification. For example, the optoelectronic device according to the present invention can include the following regions in the following order: I. A first electrode including a transparent conductive oxide, preferably FTO, II. An n-type region including at least one n-type layer, III. A layer of perovskite semiconductor without open pores, IV. A p-type region including at least one p-type layer, and V. A second electrode containing a metal, preferably silver or gold.

[0183] In some embodiments, the second electrode can alternatively include 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 includes 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 include FTO or ITO, and the second electrode can include a layer of silver having a thickness 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 can include a first electrode, a second electrode, and the photoactive region disposed between the first electrode and the second electrode, where 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. Such an architecture leads to what is known as an inverted device. These devices can have the configuration schematically shown in FIG. 8. In some situations, it is desirable to have an inverted device structure in which holes are collected through the substrate side of the device. In particular, an inverted device architecture may be required for tandem applications. Tandem applications include the use of a number of inorganic photovoltaic low band-gap cells such as CIGS. The inventors have developed a low-temperature, ambient air, solution-processable photovoltaic cell based on a semiconducting perovskite absorber. In many cases, selective p-type contacts and n-type contacts are PEDOT:PSS and PC respectively 60It can be in the form of BM. Notably, while having an exchanged photoactive layer where the bulk heterojunction is replaced by a solid perovskite film, the final electrode configuration is very similar to the electrode configuration utilized in the "bulk heterojunction" polymer solar cell, leaving quite some room for further improvement and achieving a very satisfactory 7.5% overall solar power conversion efficiency.

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

[0186] For these reasons, perovskite-based hybrid photovoltaics are an attractive alternative technology as they are processable at temperatures below 150 °C, are completely solid-state devices, and have already shown high power conversion efficiencies exceeding 12%. Perovskite absorbers have been previously used in dye-sensitized solar cells as well as in thin-film architectures. In particular, in the latter configuration, the perovskite CH3NH3PbI 3-x Cl x can act as a composite sensitizer and electron transporter when processed on an alumina mesostructured scaffold, minimizing energy losses simply because electrons directly transition to the conductive substrate through the conduction band of the perovskite. In this way, it is possible to achieve an extremely high open-circuit voltage exceeding 1.1 V.

[0187] In many cases, in perovskite solar cells, electrons are collected from the FTO substrate, while holes are collected at the metal cathode. This configuration is not desirable for some tandem applications where holes must be collected at the TCO (transparent conductive oxide) interface. Here, a novel inverted device architecture will be actually described. In many cases, this architecture is based on organic solar cells, namely, [6,6]-phenyl C61 butyric acid methyl ester (PC 60 BM) and poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS), as well as n-type and p-type materials commonly used for charge collection in V2O5 and NiO.

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

[0189] Thus, the optoelectronic device according to the present invention can include the following regions in the following order: I. The second electrode, II. An n-type region including at least one n-type layer, III. A layer of perovskite semiconductor without open pores, IV. A p-type region including at least one p-type layer, and V. The first electrode.

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

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

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

[0193] Any of the components within the inverted element according to the present invention can be as defined anywhere herein. For example, the perovskite can be a perovskite according to any one of the above chemical formulas I, Ia, II, or IIa. For example, the perovskite can be CH3NH3PbI3, CH3NH3PbBr3, CH3NH3PbCl3, CH3NH3PbF3, CH3NH3PbBrI2, CH3NH3PbBrCl2, CH3NH3PbIBr2, CH3NH3PbICl2, CH3NH3PbClBr2, CH3NH3PbI2Cl, CH3NH3SnBrI2, CH3NH3SnBrCl2, CH3NH3SnF2Br, CH3NH3SnIBr2, CH3NH3SnICl2, CH3NH3SnF2I, CH3NH3SnClBr2, CH3NH3SnI2Cl, and CH3NH3SnF2Cl. In some embodiments, the second electrode can alternatively include 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 includes 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 include FTO or ITO, and the second electrode can include a layer of silver having a thickness from 1 nm to 10 nm, for example, from 5 nm to 10 nm. The thin layer of silver can be semi-transparent.

[0194] The n-type region within the inverted element can include at least one n-type layer as defined anywhere herein with respect to the standard, non-inverted element. For example, the n-type layer can include TiO2, SnO2, ZnO, Nb2O5, Ta2O5, WO3, W2O5, In2O3, Ga2O3, Nd2O3, PbO, or CdO. In one embodiment, the n-type region can include a dense layer of titanium dioxide. In many cases, the n-type region includes a dense layer of titanium dioxide and

[60] PCBM ([6,6]-phenyl-C 61It can include a layer of methyl - butyrate). When the n - type region includes a layer of titanium dioxide and a layer of

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

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

[0195] The p - type region in the inverted device can include at least one p - type layer as defined anywhere herein with respect to the 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 can include an inorganic hole transporter including, for example, an oxide of nickel, vanadium, copper, or molybdenum. In particular, the p - type region can include a layer of spiro - OMeTAD and / or a layer of PEDOT:PSS. In one embodiment, the p - type region includes a layer of PEDOT:PSS. When the p - type region includes a layer of a p - type polymer material such as (PEDOT, or PEDOT:PSS, etc.), the p - type layer can be cross - linked. To limit the extent to which the layer dissolves in the perovskite precursor solution during device fabrication, the layer is cross - linked, that is, the polymer (e.g., PEDOT:PSS) is made insoluble by cross - linking the polymer. For example, the p - type region can include a p - type layer including a polymer material, where the p - type layer is cross - linked. Sometimes, the p - type region can include a layer of PEDOT:PSS, where the layer is cross - linked. Cross - link the p - type layer with a Lewis acid such as Fe 3+It can be crosslinked by using. The p-type region can include a layer of PEDOT:PSS, where FeCl3 is used to crosslink the layer.

[0196] The optoelectronic device according to the present invention can include the following regions in the following order: I. A second electrode containing a metal, II. An n-type region containing a dense layer of titanium dioxide and a layer of

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

[0197] The optoelectronic device according to the present invention can include the following regions in the following order: I. A second electrode containing a metal, preferably aluminum, silver or gold, II. An n-type region containing a dense layer of titanium dioxide and a layer of

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

[0198] For example, the optoelectronic device according to the present invention can include the following regions in the following order: I. A second electrode containing aluminum, II. A dense layer of titanium dioxide, III. A layer of

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

[0199] The said photoactive region can be simply the photoactive region within the device, and thus the optoelectronic device of the present invention can be a single-junction device.

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

[0201] Therefore, the optoelectronic device includes a first electrode, a second electrode, and disposed between the first electrode and the second electrode, the photoactive region, and at least one other photoactive region, and can include.

[0202] One or more other photoactive regions may be the same as or different from the photoactive regions defined previously herein.

[0203] In some embodiments, one or more other photoactive regions are the same as the photoactive regions defined previously herein.

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

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

[0206] The tandem junction optoelectronic device (or multi-junction optoelectronic device) according to the present invention can be combined with the known technology of the perovskite thin film technology disclosed herein in order to achieve optimized performance.

[0207] "All perovskite" multi-junction cells are very attractive. However, even when there is no need to develop a new absorber, when used as the upper cell in a tandem junction, CH3NH3PbI 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 including a layer of semiconductor material, and IV. A 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 having a conductivity intermediate in magnitude between that of a conductor and that of an insulator. Typically, a semiconductor material has a conductivity from 10 3 to 10 -8 Scm -1It is a material having a conductivity up to. Standard techniques such as the four-probe conductivity measurement method can be used to measure the conductivity. Examples of semiconductor materials include oxides or chalcogenides of metallic or metalloid elements; group IV compounds; compounds containing group III elements and group V elements; compounds containing group II elements and group VI elements; compounds containing group I elements and group VII elements; compounds containing group IV elements and group VI elements; compounds containing group V elements and group VI elements; compounds containing group II elements 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); III-V semiconductors (e.g., gallium arsenide); II-VI semiconductors (e.g., cadmium selenide); I-VII semiconductors (e.g., cuprous chloride); IV-VI semiconductors (e.g., lead selenide); V-VI semiconductors (e.g., bismuth telluride); and 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., CH3NH3PbI3 and CH3NH3PbI2Cl); and organic semiconductor materials (e.g., conjugated polymer compounds containing 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 that are of course conductors, and electrical insulators or dielectrics such as silica or calcite.

[0212] As used herein, the term "oxide" refers to at least one oxygen ion (i.e., O2- ) or a compound containing a divalent oxygen atom. It should be understood that the terms "metal oxide" and "oxide of a metal element" as used herein encompass both oxides containing one metal and also mixed metal oxides. To avoid ambiguity, a mixed metal oxide refers to a single oxide compound containing more than one metal element. Examples of mixed metal oxides include zinc tin oxide and indium tin oxide. Similarly, it should be understood that the terms "metalloid oxide" and "oxide of a metalloid element" as used herein encompass oxides containing one metalloid element and also mixed metalloid oxides. To avoid ambiguity, a mixed metalloid oxide refers to a single oxide compound containing more than one metalloid element.

[0213] As used herein, the term "chalcogenide" refers to a sulfide ion, selenide ion, or telluride ion (i.e., S 2- , Se 2- , or Te 2- ), or a compound containing at least one of a divalent sulfur atom, selenium atom, or tellurium atom. It should be understood that the terms "metal chalcogenide" and "chalcogenide of a metal element" encompass chalcogenides containing one metal and also mixed metal chalcogenides. To avoid ambiguity, a mixed metal chalcogenide refers to a single chalcogenide compound containing more than one metal element. Similarly, it should be understood that the terms "metalloid chalcogenide" and "chalcogenide of a metalloid element" as used herein encompass chalcogenides containing one metalloid and also mixed metalloid chalcogenides. To avoid ambiguity, a mixed metalloid chalcogenide refers to a single chalcogenide compound containing more than one metalloid element.

[0214] Sometimes, the semiconductor material includes oxides or chalcogenides of metal elements or metalloid elements. For example, the semiconductor material is composed of oxides or chalcogenides of metal elements or metalloid elements. For example, the semiconductor material includes oxides of titanium, niobium, tin, zinc, cadmium, copper or lead or any combination thereof; or chalcogenides 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 can be a doped semiconductor, where the impurity element is present at a concentration in the range of 0.01% to 40%. When the impurity element acts as an electron donor, the semiconductor material will be doped to be n-type, and when the impurity element acts as an electron acceptor, the semiconductor material will be doped to be p-type. Note that for a metal oxide doped with an impurity metalloid element that replaces the main metalloid element, when the valence of the dopant is greater than the valence of the main metalloid element, the metal oxide will be doped n-type, and when the valence of the dopant metalloid element is less than the valence of the main metalloid element, the metal oxide will be doped p-type. It is possible to use any of the above-described elements to dope any of the above-described semiconductor materials to different levels of efficacy and effect.

[0216] Thus, in some cases, the semiconductor material includes oxides or chalcogenides of metal elements or metalloid elements; group IV compounds; compounds containing group III elements and group V elements; compounds containing group II elements and group VI elements; compounds containing group I elements and group VII elements; compounds containing group IV elements and group VI elements; compounds containing group V elements and group VI elements; compounds containing group II elements and group V elements; ternary or quaternary compound semiconductors; or organic semiconductors.

[0217] In many cases, the semiconductor material includes silicon; 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; copper indium gallium diselenide, silicon carbide, gallium arsenide, cadmium selenide, cuprous chloride, lead selenide, bismuth telluride, or cadmium arsenide. When the semiconductor material includes silicon, the silicon can be single crystal, polycrystalline or amorphous.

[0218] The photoactive region according to the present invention can be made into a 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 includes the following regions in the following order: I. A first electrode, II. A first photoactive region as defined anywhere herein, III. A layer (A) of a p-type semiconductor, IV. A first layer of an intrinsic semiconductor, V. A layer (B) of a p-type semiconductor or a layer (B) of an n-type semiconductor, VI. A second layer of an intrinsic semiconductor, VII. A layer (C) of an n-type semiconductor, and VIII. A second electrode.

[0220] Sometimes, the optoelectronic device includes the following regions in the following order: I. A first electrode, II. A first region, III. A layer of a perovskite semiconductor without open pores, IV. A third region, V. A layer (A) of a p-type semiconductor, 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 (C) of an n-type semiconductor, and X. A second electrode, Here, 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.

[0221] Any of the components (e.g., perovskite, the first region or the third region) within this tandem element can be as defined anywhere herein. Any of the p-type semiconductor, n-type semiconductor or intrinsic semiconductor mentioned can include any semiconductor defined herein that can be appropriately p-doped, n-doped or not doped.

[0222] In many cases, 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. Thus, the p-type layer will be adjacent to the first electrode, and the perovskite photoactive region according to the present invention will be inverted. Typically, the light incident on the element enters through the first electrode. The n-type region including at least one n-type layer can be as defined herein and / or the p-type region including at least one p-type layer can be as defined herein.

[0223] In many cases, in the tandem optoelectronic device according to the present invention, the layer (A) of the p-type semiconductor is a layer of p-type amorphous silicon and / or the layer (C) of the n-type semiconductor is a layer of n-type amorphous silicon. Typically, the layer (A) of the p-type semiconductor is a layer of p-type amorphous silicon, and the layer (C) of the n-type semiconductor is a layer of n-type amorphous silicon. In many cases, the first layer of the intrinsic semiconductor is a layer of intrinsic amorphous silicon and / or the second layer of the intrinsic semiconductor is a layer of intrinsic amorphous silicon. Sometimes, the first layer of the intrinsic semiconductor is a layer of intrinsic amorphous silicon, and the second layer of the intrinsic semiconductor is a layer of intrinsic amorphous silicon. In the tandem element, the layer (B) of the p-type semiconductor or the layer (B) of the n-type semiconductor 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 includes a transparent conductive oxide and / or the second electrode includes a metal. In many cases, the first electrode typically includes a transparent conductive oxide and the second electrode includes a metal. The transparent conductive oxide can be as defined above, and in many cases is FTO, ITO, or AZO, and typically is ITO. The metal can be any metal. Generally, the second electrode includes a metal selected from silver, gold, copper, aluminum, platinum, palladium, or tungsten. This list of metals can also apply to other instances of the second electrode in this specification. In many cases, the first electrode material includes ITO and / or the second electrode includes silver. Typically, the first electrode material includes ITO and the second electrode includes silver.

[0225] Rather than being a tandem with a silicon photoactive region, the photoactive region according to the present invention including a layer of perovskite without open pores can be a tandem with a thin-film photoactive region. For example, the optoelectronic device can include the following regions in the following order: I. A first electrode, II. A first photoactive region as defined somewhere previously herein, III. A second photoactive region including a layer of a semiconductor material, and IV. A second electrode, wherein 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 the semiconductor material can be a thin film of the semiconductor material.

[0226] In one embodiment, the optoelectronic device includes the following regions in the following order: I. A first electrode, II. A first photoactive region as defined previously herein, III. A layer of a transparent conductive oxide, IV. A layer of an 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, and VI. A second electrode.

[0227] For example, the optoelectronic device according to the present invention can include the following regions in the following order: I. A first electrode, II. A first region, III. A layer of perovskite semiconductor without open pores, IV. A third region, V. A layer of transparent conductive oxide, VI. A layer of n-type semiconductor (D), VII. 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, and VIII. A second electrode, wherein the first region is an n-type region containing at least one n-type layer, the third region is a p-type region containing at least one p-type layer, or the first region is a p-type region containing at least one p-type layer, and the third region is an n-type region containing at least one n-type layer.

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

[0229] Typically, in a tandem device including thin films of semiconductors, the first region is an n-type region containing at least one n-type layer, and the third region is a p-type region containing at least one p-type layer. The n-type region containing at least one n-type layer can be as defined somewhere herein, and / or the p-type region containing at least one p-type layer can be as defined somewhere 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 can be a photovoltaic device; a photodiode; a phototransistor; a photomultiplier tube; a photoresistor; a photodetector; a photosensitive detector; a solid triode; a battery electrode; a light-emitting device; 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 can be a solar cell.

[0234] In another preferred embodiment, the optoelectronic device of the present invention is a light-emitting device, such as a light-emitting diode.

[0235] The perovskite compound used in the optoelectronic device of the present invention in the layer of the perovskite semiconductor without open pores and / or in the first layer: (a) A first compound comprising (i) a first cation and (ii) a first anion, (b) can be produced by a process comprising mixing with a second compound comprising (i) a second cation and (ii) a second anion, wherein the first cation and the second cation are as defined herein with respect to perovskite, and the first anion and the second anion may be the same anion or different anions.

[0236] ​ A perovskite containing at least one anion selected from halide anions and chalcogenide anions can be, for example, (a)(i) a first compound comprising a first cation and (ii) a first anion, (b) mixed with a second compound comprising (i) a second cation and (ii) a second anion by a process comprising mixing, wherein the first cation and the second cation are as defined herein with respect to the perovskite, and the first anion and the second anion may be the same anion 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 this process can contain additional cations or additional anions. For example, the perovskite can contain two, three or four different cations, or two, three or four different anions. The process for producing the perovskite can therefore include mixing additional compounds containing additional cations or additional anions. Additionally or alternatively, the process for producing the perovskite can include mixing (a) and (b) with: (c)(i) a third compound comprising a first cation and (ii) a second anion, or (d)(i) a fourth compound comprising a second cation and (ii) a first anion.

[0239] Typically, in the process for manufacturing perovskite, 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 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+ selected from. Usually, the second cation is selected from Sn 2+ and Pb 2+ .

[0240] In many cases, in the process for manufacturing perovskite, the first cation in the mixed anion perovskite is an organic cation.

[0241] Usually, the organic cation has the chemical formula (R1R2R3R4N) + where R1 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R2 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R3 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, and R4 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl.

[0242] Primarily, in the organic cation, R1 is hydrogen, methyl or ethyl, R2 is hydrogen, methyl or ethyl, R3 is hydrogen, methyl or ethyl, and R4 is hydrogen, methyl or ethyl. For example, R1 can be hydrogen or methyl, R2 can be hydrogen or methyl, R3 can be hydrogen or methyl, and R4 can be hydrogen or methyl.

[0243] Alternatively, the organic cation can have the chemical formula (R5NH3) + wherein R5 is hydrogen, or unsubstituted or substituted C1 - C 20 alkyl. For example, R5 can be methyl or ethyl. Typically, R5 is methyl.

[0244] Alternatively, the organic cation can have the chemical formula (R5R6N=CH-NR7R8) + wherein R5 is hydrogen, unsubstituted or substituted C1 - C 20 alkyl, or unsubstituted or substituted aryl; R6 is hydrogen, unsubstituted or substituted C1 - C 20 alkyl, or unsubstituted or substituted aryl; R7 is hydrogen, unsubstituted or substituted C1 - C 20 alkyl, or unsubstituted or substituted aryl; and R8 is hydrogen, unsubstituted or substituted C1 - C 20 alkyl, or unsubstituted or substituted aryl.

[0245] Typically, in the cation (R5R6N=CH-NR7R8) + R5 is hydrogen, methyl or ethyl, R6 is hydrogen, methyl or ethyl, R7 is hydrogen, methyl or ethyl, and R8 is hydrogen, methyl or ethyl. For example, R5 can be hydrogen or methyl, R6 can be hydrogen or methyl, R7 can be hydrogen or methyl, and R8 can be hydrogen or methyl.

[0246] The organic cation can have, for example, the chemical formula (H2N=CH-NH2) + and can have the following formula

[0247] In a process for manufacturing 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 manufacturing a perovskite, the perovskite is a perovskite compound of chemical formula (I): [A][B][X]3 (I) where [A] is at least one organic cation, [B] is at least one metal cation, and [X] is said at least one anion, and the process comprises (a)(i) a first compound comprising a metal cation and (ii) a first anion, (b) mixing with a second compound comprising (i) an organic cation and (ii) a second anion where the first anion and the second anion are different anions selected from halide anions or chalcogenide anions.

[0249] The perovskite of chemical formula (I) can comprise, for example, one, two, three or four different metal cations, typically one or two different metal cations. The perovskite of chemical formula (I) can comprise, for example, one, two, three or four different organic cations, typically one or two different organic cations. The perovskite of chemical formula (I) can comprise, for example, two, three or four different anions, typically two or three different anions. The process can therefore comprise mixing further compounds comprising 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 includes (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] In many cases, in the process for producing a perovskite, the perovskite has the chemical formula (IA): AB[X]3 (IA) is a perovskite compound, where A is an organic cation, B is a metal cation, and [X] is the two or more different anions, The process (a) includes mixing a first compound including (i) a metal cation and (ii) a first halide anion, (b) with a second compound including (i) an organic cation and (ii) a second halide anion, where 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 a perovskite, the perovskite has the chemical formula (II): ABX 3-yX' 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 a perovskite, the first compound is BX2 and the second compound is AX'.

[0257] In many cases, the second compound is produced by reacting a compound of the formula (RNH), where R is hydrogen or an unsubstituted or substituted C-C 20It is alkyl and has a compound of chemical formula HX'. Typically, R5 can be methyl or ethyl, and in many cases, R5 is methyl.

[0258] Generally, the compound of chemical formula (R5NH2) and the compound of chemical formula HX' react in a 1:1 molar ratio. In many cases, the reaction is carried out under a nitrogen atmosphere and usually in anhydrous ethanol. Typically, the anhydrous ethanol is about 200 proof. More typically, 15 ml to 30 ml of the compound of chemical formula (R5NH2) is reacted with about 15 ml to 15 ml of HX' in about 50 ml to 150 ml of anhydrous ethanol under a nitrogen atmosphere. The process can also include the step of recovering the mixed anion perovskite. A rotary evaporation apparatus is often used to extract the crystal AX'.

[0259] Generally, the step of mixing the first compound and the second compound is the 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:dimethylformamid) or water. When the metal cation is Pb 2+ then the solvent is usually dimethylformamide. When the metal cation is Sn 2+ then the solvent is usually water. The use of DMF or water as the solvent is advantageous because these solvents are not very volatile.

[0260] The perovskite semiconductor layer in the device of the invention can be prepared by solution processing or by evaporation in a vacuum. The low processing temperature is important for reducing manufacturing costs, enabling processing on plastic substrates and on other layers, and enabling the manufacture of tandem junctions and multi-junction solar cells. Here, the inventors have actually demonstrated that the device of the invention can operate using all layers processed at low temperatures, including a solution-processable scaffold.

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

[0262] In many cases, 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.

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

[0264] In one embodiment of the process of the present invention, step (b) of disposing the second region on top of the first region comprises generating a solid layer of perovskite on top of the first region by vapor deposition, and

[0265] in this embodiment, the step of generating the solid layer by vapor deposition typically (i) exposing a first region to vapor that comprises the perovskite or one or more reactants for forming the perovskite, (ii) enabling deposition of the vapor onto the first region to form a solid layer of the perovskite thereon, comprising.

[0266] The perovskite in the vapor can be any of the perovskites discussed previously herein for use in an optoelectronic device of the invention, typically a perovskite of chemical formula (I), (IA) or (II) as defined previously herein.

[0267] One or more reactants for forming the perovskite can include reactants of the type discussed above with respect to the process for synthesizing a perovskite compound.

[0268] Thus, one or more reactants are as defined previously herein with respect to the process for forming a perovskite compound for use in an optoelectronic device of the 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, can comprise.

[0269] More particularly, one or more reactants can (a) a first compound comprising (i) a metal cation and (ii) a first anion, and (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 previously herein with respect to the process for forming a perovskite compound for use in an optoelectronic device of the invention.

[0270] For example, one or more reactants can include (a)(i) a first compound comprising a metal cation and (ii) a first halide anion, and (b)(i) an organic cation and (ii) a second halide anion wherein the first halide anion and the second halide anion are different halide anions as previously defined herein with respect to a process for forming a perovskite compound for use in the optoelectronic device of the present invention.

[0271] For example, when the perovskite to be deposited is CH3NH3PbI2Cl, the one or more reactants typically include (a) PbI2 and (b) CH3NH3Cl.

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

[0273] To form a solid layer of the perovskite over the first region, the resulting vapor is then brought into contact with the first region, thereby depositing. When reactants are used, they react together in situ to form the perovskite over the first region.

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

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

[0276] The inventors have found that a dual-source vapor deposition process enables 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 has conventionally referred to the deposition of thin films by the aggregation in the form of vapor deposition of a desired film material onto a surface in a vacuum. Deposition methods for inorganic perovskites such as pulsed laser deposition and chemical solution deposition have been well studied. Hybrid inorganic-organic perovskites such as (C6H5C2H4NH3)2PbI4 or (C6H5C2H4NH3)2PbBr4 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, there is little description of deposition methods for hybrid inorganic-organic perovskites, so dual-source thermal deposition was applied to deposit organic and inorganic sources simultaneously but independently controlled (V. K. Dwivedi, J. J. Baumberg, and G. V. 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 proposed to obtain a new type of hybrid perovskite (C 12 H 25 NH3)2PbI4, which are also proposed to be directly etched into a 2D photonic structure that should be very useful in photovoltaic devices. Deposition of hybrid organic-inorganic perovskite materials is always a challenge because most organic materials are very volatile and easily decomposed, which makes the control of the deposition process more complicated.

[0277] In one embodiment, step (b) of disposing the second region over the first region is Including generating a perovskite solid layer by vapor deposition, where the vapor deposition is dual-source vapor deposition.

[0278] As used herein, the term "dual-source vapor deposition" 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 generate a vapor containing a first component and a second source will generate a vapor containing a second component. Although dual-source deposition is commonly preferred, dual-source vapor deposition can also be extended to include three-source and four-source vapor deposition.

[0279] In one embodiment, step (b) of disposing a second region over a first region comprises (i) exposing the first region to a vapor that contains two reactants for forming the perovskite, and (ii) enabling deposition of the vapor onto the first region to form a perovskite solid layer over the first region, wherein the method further comprises generating the vapor containing two reactants for forming the perovskite by evaporating a first reactant from a first source and evaporating a second reactant from a second source. The reactants can be as defined herein for the formation of the perovskite. 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.

[0280]

[0281] ​In many cases, the first reactant comprises a first compound containing (i) a first cation and (ii) a first anion; and the second reactant comprises a second compound containing (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 containing (i) a metal cation and (ii) a first anion; and the second reactant can comprise a second compound containing (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+ selected as the cation. Among these cations, the divalent metal cation is preferably Pb 2+ or Sn 2+ .

[0282] In many cases, the organic cation has the chemical formula (R1R2R3R4N) + , where R1 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R2 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R3 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, and R4 is hydrogen, or unsubstituted or substituted C1-C 20It is alkyl, or unsubstituted or substituted aryl.

[0283] The organic cation can be as defined anywhere herein. In many cases, the organic cation has the chemical formula (R5NH3) + wherein R5 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl. For example, the organic cation has the chemical formula (R5NH3) + wherein R5 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 has the chemical formula (R5R6N=CH-NR7R8) + wherein R5 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; R6 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; R7 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl; and R8 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl.

[0285] Typically, in the cation (R5R6N=CH-NR7R8) + R5 is hydrogen, methyl or ethyl, R6 is hydrogen, methyl or ethyl, R7 is hydrogen, methyl or ethyl, and R8 is hydrogen, methyl or ethyl. For example, R5 can be hydrogen or methyl, R6 can be hydrogen or methyl, R7 can be hydrogen or methyl, and R8 can be hydrogen or methyl.

[0286] The organic cation can have, for example, the chemical formula (H2N=CH-NH2) + ​

[0287] The first anion and the second anion can be any anions, but are typically selected from halide ions (e.g., fluoride ion, chloride ion, bromide ion, and iodide ion) or chalcogenide ions (e.g., sulfide ion, selenide ion, and telluride ion). 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 comprise a metal dihalide and the second reactant will comprise a halogenated salt of an organic acid. For example, the first reactant can comprise a first compound that is BX2, and the second reactant can comprise 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 cation and the anion can be as defined above. Sometimes, the first reactant comprises a first compound that is BX2 and the second reactant comprises a second compound that is AX', where B is Ca2+ 、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 cation of the chemical formula (R5NH3) + where R5 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, X’ is F - 、Cl - 、Br - and I - is an anion selected from, and X and X’ are different anions.

[0289] The first reactant can include lead halide or tin halide, and the second reactant can include methylammonium halide or ethylammonium halide, where the halide ions in the first reactant and the second reactant are different. In many cases, the first reactant includes tin fluoride, and the second reactant includes methylammonium chloride, methylammonium bromide or methylammonium iodide, The first reactant includes lead chloride or tin chloride, and the second reactant includes methylammonium bromide or methylammonium iodide, The first reactant includes lead bromide or tin bromide, and the second reactant includes methylammonium chloride or methylammonium iodide, or The first reactant contains lead iodide or tin bromide, and the second reactant contains methylammonium chloride or methylammonium bromide.

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

[0291] These pairs of compounds are applied to another deposition method of perovskite, for example, solution deposition.

[0292] Alternatively, A can be an inorganic monovalent cation. For example, A can be a cation of a Group 1 metal such as Cs + When A is inorganic, the two halide anions in each reactant may be the same or different. For example, the first reactant can contain a first compound BX2, and the second reactant can contain 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 an anion selected from F - , Cl - , Br - and I - is an anion selected from, A is Cs + and X’ is an anion selected from F - , Cl - , Br - and I - is an anion selected from, and X and X’ are the same or different.

[0293] Dual vapor deposition using these reactants can produce a layer of perovskite of chemical formula (IB) as defined above, for example, CsSnBr3. Alternatively, CsSnBr 3-y I y (where y is as defined in the above chemical formula (II)) can be produced.

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

[0295] Vapor deposition is generally carried out in a chamber having a pressure of less than 10 -2 Pa (10 -4 mbar), for example, less than 10 -3 Pa (10 -5 mbar). The step of depositing a second region over a first region by vapor deposition typically further includes (iii) heating the solid layer of perovskite thus produced.

[0296] The step of heating the perovskite solid layer typically involves heating the perovskite solid layer in an inert atmosphere. Typically, the temperature at which the perovskite solid layer is heated does not exceed 150°C. Thus, the perovskite solid layer can be heated at a temperature from 30°C to 150°C, and preferably from 40°C to 110°C. The perovskite solid layer can be heated at the above temperature until it has the desired semi-conductive properties. Usually, the perovskite solid layer is heated for at least 30 minutes, preferably for at least 1 hour. In some embodiments, the perovskite solid layer is heated until the desired semi-conductive properties are obtained, and the properties can be measured by standard methods for measuring conductivity and resistivity. In some cases, the perovskite solid layer is heated until a color change is observed, which indicates that the desired semi-conductive properties have been obtained. In the case of CH3NH3PbI2Cl perovskite, the color change is typically from yellow to brown.

[0297] The second region can be disposed on top of the first region by a method that includes disposing a solid layer of a first compound (first perovskite precursor) on top of the first region and then treating the layer disposed with a solution of a second compound (second perovskite precursor). This can be referred to as the "two-step method". The solid layer of the first perovskite precursor can be disposed by vacuum deposition. This solid layer is then treated with a solution of the second perovskite precursor. The second precursor in the solution then reacts with the solid layer in which the first perovskite precursor is present to form a solid layer of perovskite. For example, the solid layer of the 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 the 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 the second cation are as defined herein with respect to perovskite generally, and the first anion and the second anion may be the same or different and may be as defined herein with respect to the first anion and the second anion.

[0299] In one embodiment, step (b) of disposing the second region over the first region comprises (i) exposing the first region to a vapor that comprises the first perovskite precursor compound and that enables deposition of the vapor onto the first region to produce a solid layer of the first perovskite precursor compound over the first region, and (ii) treating the resulting solid layer of the first perovskite precursor compound with a solution that comprises the second perovskite precursor compound, thereby reacting the first perovskite precursor compound and the second perovskite precursor compound to produce the layer of perovskite semiconductor free of open pores. wherein 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 can be as defined anywhere herein with respect to perovskite.

[0301] 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 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+ selected cations. Among these cations, the divalent metal cation is preferably Pb 2+ or Sn 2+ .

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

[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 (R1R2R3R4N) + , (R5NH3) + , or (R5R6N=CH-NR7R8) + and R1 to R8 can be as defined above.

[0306] In many cases, the first compound has the chemical formula BX2 and the second compound has the chemical formula AX’, where B is a cation 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+ and X is an anion selected from F - , Cl - , Br - and I - and A is a cation of the chemical formula (R5NH3) + wherein R5 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, X’ is F - , Cl - Br - and I - and is an anion selected from, 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, this is lead chloride or lead iodide. In many cases, the second perovskite precursor compound can be selected from methylammonium fluoride, methylammonium chloride, methylammonium bromide, methylammonium iodide, ethylammonium fluoride, ethylammonium chloride, ethylammonium bromide, or ethylammonium iodide. Typically, this is methylammonium iodide.

[0308] Typically, the vapor deposition of the first perovskite precursor compound can continue 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, the vapor deposition can continue until the solid layer of the first compound has a thickness from 50 nm to 1000 nm, or for example, from 100 nm to 700 nm. For example, deposition can continue until a first compound of approximately 100 nm to 300 nm is deposited onto the first region.

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

[0310] The deposition rate of the first compound can be from 0.1 to 10 Å / s, or from 1 to 5 Å / s. Chemical vapor deposition is generally carried out at a pressure of less than 10 -2 Pa (10 -4 mbar), for example, at a pressure of less than 10 -3 Pa (10 -5 mbar) in a chamber. 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, to enable the formation of the second region, step (iii) of contacting the obtained solid layer of the first compound with a solution containing the second compound involves immersing the substrate comprising the solid layer of the first compound in the solution containing the second compound for a sufficient time to form the second region, i.e., a layer of perovskite semiconductor without open pores. Step (iii) can involve immersing the substrate comprising the solid layer of the first compound in the solution containing the second compound for from 1 to 60 minutes, or from 5 to 15 minutes. Immersing the substrate comprising the solid layer of the first compound in the solution containing the second compound can be referred to as immersion coating.

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

[0313] After contacting the obtained solid layer of the first perovskite precursor compound with a solution containing the second compound (e.g., by immersion coating) to enable the formation of the second region, the substrate can be annealed. For example, the substrate can be heated from 80 °C to 200 °C, or from 100 °C to 150 °C. The substrate can be heated for from 1 to 60 minutes, or from 5 to 15 minutes. The substrate can be annealed in a nitrogen atmosphere.

[0314] The solution deposition method can be used to dispose a second region over a first region. Thus, in some embodiments, step (b) of disposing a second region over a first region is (i) disposing one or more precursor solutions over the first region, the one or more precursor solutions including the perovskite dissolved in a solvent, or one or more reactants for forming the perovskite dissolved in one or more solvents, and (ii) removing one or more solvents to form a solid layer of perovskite over the first region, and includes.

[0315] Again, the perovskite can be any of the perovskites previously discussed herein for use in the optoelectronic device of the present invention, typically a perovskite of chemical formula (I), (IA) or (II) as previously defined herein.

[0316] Also, one or more reactants for forming the perovskite can include reactants of the type discussed above for a process for synthesizing a perovskite compound.

[0317] Thus, one or more reactants are as defined herein with respect to a process for forming a perovskite compound utilized in the optoelectronic device of the present invention (a) (i) a first compound including a first cation and (ii) a first anion, and (b) (i) a second compound including a second cation and (ii) a second anion, and can include.

[0318] More specifically, one or more reactants are (a) (i) a first compound including a metal cation and (ii) a first anion, and (b)(i) an organic cation and (ii) a second compound comprising a second anion, wherein the first anion and the second anion are different anions selected from halide anions or chalcogenide anions as previously defined herein with respect to a process for forming a perovskite compound for use in the optoelectronic device of the present invention. The organic cation can be as defined herein with respect to a process for forming a perovskite.

[0319] For example, one or more reactants (a)(i) a first compound comprising a metal cation and (ii) a first halide anion, (b)(i) an organic cation and (ii) a second compound comprising a second halide anion, wherein the first halide anion and the second halide anion are different halide anions as previously defined herein with respect to a process for manufacturing a perovskite compound for use in the optoelectronic device of the present invention.

[0320] For example, when the perovskite to be deposited is CH3NH3PbI2Cl, one or more reactants typically comprise (a) PbI2 and (b) CH3NH3Cl.

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

[0322] ​The perovskite can be any of the perovskites discussed previously herein for use in the optoelectronic device of the present invention, and is typically a perovskite of chemical formula (I), (IA) or (II) as defined previously herein.

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

[0324] One or more precursor solutions can be disposed onto the first region by spin-coating onto the first region to form the solid layer of perovskite on the first region.

[0325] The step of disposing one or more precursor solutions onto the first region and the step of 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 step of disposing one or more precursor solutions onto the first region and the step of removing one or more solvents can be performed until the solid layer of perovskite has a thickness from 50 nm to 1000 nm, or for example, from 100 nm to 700 nm.

[0326] The step of disposing one or more precursor solutions onto the first region and the step of removing one or more solvents can be performed until the solid layer of perovskite has a thickness 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 thus formed perovskite solid layer.

[0328] The step of heating the perovskite solid layer typically comprises heating the perovskite solid layer in an inert atmosphere. Typically, the temperature at which the perovskite solid layer is heated does not exceed 150°C. Thus, the perovskite solid layer can be heated at a temperature from 30°C to 150°C, and preferably at a temperature from 40°C to 110°C. The perovskite solid layer can be heated at said temperature until it has the desired semi-conductive properties. Typically, the perovskite solid layer is heated for at least 30 minutes, preferably for at least 1 hour. In some embodiments, the perovskite solid layer is heated until the desired semi-conductive properties are obtained, and the properties can be measured by standard methods for measuring conductivity and resistivity. In some cases, the perovskite solid layer is heated until a color change is observed, which indicates that the desired semi-conductive properties have been obtained. In the case of CH3NH3PbI2Cl perovskite, the color change is typically from yellow to brown.

[0329] In some embodiments of the process of the present invention (for example, when the photoactive region of the device to be manufactured does not have a scaffold material), the second region is composed of said layer of the perovskite semiconductor without open pores.

[0330] In another embodiment of the process of the present invention, in any way, the photoactive region is said n-type region, said p-type region, and 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 top of said first layer, said capping layer being said layer of perovskite semiconductor without open pores, Here, the perovskite semiconductor in the capping layer contacts the perovskite semiconductor in the first layer, and the process comprises (a) providing the first region, (b) disposing the second region over the first region, where the second region comprises (i) a first layer comprising a scaffold material and a perovskite semiconductor, and (ii) a capping layer over the first layer, the capping layer being the layer of perovskite semiconductor without open pores, where the perovskite semiconductor in the capping layer contacts the perovskite semiconductor in the first layer, and (c) disposing the third region over the second region and including.

[0331] Generally, 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 example, step (b) of disposing the second region over the first region comprises (i) disposing a scaffold material over the first region, and (ii) disposing the perovskite within the pores of the scaffold material to form the first layer, and further disposing the perovskite over the first layer to form the capping layer. Typically, the “disposing” of the perovskite within the pores of the scaffold material and the “further disposing” of the perovskite over the first layer are carried out together in a single step, for example, by a solution deposition step or by vapor deposition. These are typically carried out by solution deposition.

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

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

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

[0335] The membrane 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 binder present, or if no binder is present, 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 disposing the scaffold material on 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 scaffold composition does not contain a binder, and the temperature at which the scaffold composition is heated does not exceed 150°C.

[0339] Thus, typically, step (i) of disposing the scaffold material on the first region comprises disposing the scaffold composition onto the first region, the scaffold composition comprising the scaffold material and one or more solvents, and removing the one or more solvents. is included.

[0340] Typically, step (i) of disposing the scaffold material on the first region further comprises heating the scaffold composition to a temperature not exceeding 150°C. Typically, the scaffold composition is heated to a temperature between 60°C and 150°C. The scaffold composition is heated to the said temperature for an appropriate period of time, for example until all the solvents are removed. Typically, the scaffold composition is heated to the said temperature for at least 30 minutes, more typically for at least 1 hour, or at least 90 minutes.

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

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

[0343] One or more solvents used 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 inventors have shown that by varying the ratio of the two or more solvents, it is possible to adjust the porosity of the scaffold material disposed on the first region, so the use of two or more solvents having different viscosities and boiling points is advantageous. The two or more solvents can include, for example, two or more different alcohols, such as 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, tert-butanol, and terpineol.

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

[0345] A solution deposition method can be used to dispose the perovskite into the pores of the scaffold material to form the first layer and to further dispose the perovskite onto the first layer to form the capping layer. Thus, in some embodiments, the step of disposing the perovskite into the pores of the scaffold material to form the first layer and the step (ii) of further disposing the perovskite onto the first layer to form the capping layer are Dispensing one or more precursor solutions onto a scaffold material, said one or more precursor solutions comprising said perovskite dissolved in a solvent, or one or more reactants for forming said perovskite dissolved in one or more solvents, and Removing one or more solvents to form a solid perovskite within the pores of the scaffold material and a solid capping layer of perovskite disposed on top of the first layer comprises.

[0346] The perovskite can be any of the perovskites previously discussed herein with respect to the optoelectronic device of the present invention, typically a perovskite of chemical formula (I), (IA) or (II) as previously defined herein.

[0347] Also, the one or more reactants for forming said perovskite can comprise reactants of the type discussed above with respect to the process for synthesizing a perovskite compound.

[0348] Thus, the one or more reactants are as previously defined herein with respect to the process for forming a perovskite compound to be utilized in the optoelectronic device of the present invention, (a) (i) a first compound comprising a first cation and (ii) a first anion, and (b) (i) a second compound comprising a second cation and (ii) a second anion, can comprise.

[0349] More specifically, the one or more reactants are (a) (i) a first compound comprising a metal cation and (ii) a first anion, and (b) (i) a second compound comprising an organic cation and (ii) a second anion comprising, wherein the first anion and the second anion are different anions selected from halide anions or chalcogenide anions as previously defined herein with respect to the process for forming the perovskite compound utilized in the optoelectronic device of the present invention.

[0350] For example, one or more reactants are as previously defined herein with respect to the process for forming the perovskite compound utilized in the optoelectronic device of the present invention. (a) a first compound comprising (i) a metal cation and (ii) a first halide anion, and (b) a second compound comprising (i) an organic cation and (ii) a second halide anion, wherein the first halide anion and the second halide anion are different halide anions.

[0351] For example, when the perovskite to be deposited is CH3NH3PbI2Cl, the one or more reactants typically comprise (a) PbI2 and (b) CH3NH3Cl.

[0352] Typically, the step of disposing the perovskite into the pores of the scaffold material to form the first layer and the step (ii) of further disposing the perovskite on top of the first layer to form the capping layer comprise disposing a precursor solution on top of the scaffold material, the precursor solution comprising the perovskite dissolved in a solvent, and removing the solvent to form a solid perovskite within the pores of the scaffold material and a solid capping layer of perovskite disposed on top of the first layer. comprise.

[0353] The perovskite can be any of the perovskites previously discussed herein with respect to the optoelectronic device of the present invention, and is typically a perovskite of chemical formula (I), (IA) or (II) as previously defined herein.

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

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

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

[0357] The step of heating the perovskite typically involves heating the perovskite in an inert atmosphere, for example, under nitrogen. Typically, the temperature at which the perovskite is heated does not exceed 150 °C. Thus, the perovskite can be heated at a temperature from 30 °C to 150 °C, and preferably from 40 °C to 110 °C. The perovskite can be heated at said temperature until it has the desired semi-conductive properties. Usually, the perovskite is heated for at least 30 minutes, preferably for at least 1 hour. In some embodiments, the perovskite is heated until it has the desired semi-conductive properties, and the properties can be measured by standard methods for measuring conductivity and resistivity. In some cases, the perovskite is heated until a color change is observed, which indicates that the desired semi-conductive properties have been obtained. In the case of CH3NH3PbI2Cl perovskite, the color change is typically from yellow to brown.

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

[0359] The process of the invention for manufacturing an optoelectronic device can further comprise, in any way, the step of disposing a first region on a first electrode This step is generally carried out before the step of disposing a second region on the first region.

[0360] The first electrode and the second electrode are an anode and a cathode, and one or both of them are transparent to allow the entry of light. The choice of the first electrode and the second electrode may depend on the structural type.

[0361]

[0362] ​Typically, the first electrode, on which the second region is disposed on top, is tin oxide, more typically fluorine-doped tin oxide (FTO), which is usually a transparent or translucent material. Thus, the first electrode is usually transparent or translucent and typically includes FTO. Usually, the thickness of the first electrode is from 200 nm to 600 nm, more generally from 300 nm to 500 nm. For example, the thickness can be 400 nm. Typically, FTO is coated onto a glass sheet. In many cases, the FTO-coated glass sheet is etched with zinc powder and an acid to generate the required electrode pattern. Usually, the acid is HCl. In many cases, the concentration of HCl is about 2 moles. Typically, the sheet is washed and then treated under oxygen plasma, usually to remove all organic residues. Usually, the treatment under oxygen plasma is for 1 hour or less, typically about 5 minutes. The first electrode and the second electrode can be as described anywhere herein. For example, the first electrode may be composed of FTO, ITO, or AZO.

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

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

[0365] Such methods can be applied to other p-type or n-type inorganic materials for generating the n-type and p-type layers within the optoelectronic device of the present invention.

[0366] Deposition of an organic, molecular or polymeric hole transport material or electron transport material can be achieved by spin coating a solution of the material in a suitable solvent. A p-type hole transport material, for example, spiro-OMeTAD, is typically dissolved in chlorobenzene. Usually, the concentration of spiro-OMeTAD in chlorobenzene is from 150 to 225 mg / ml, more generally the concentration is about 180 mg / ml. Additives can be added to the hole transport material or electron transport material. The additives can be, for example, tBP, Li-TFSi, an ionic liquid or an ionic liquid having a mixed halide.

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

[0368] Typically, the second electrode includes a metal with a large work function, such as gold, silver, nickel, palladium, or platinum, typically silver. Typically, the thickness of the second electrode ranges from 50 nm to 250 nm, more generally from 100 nm to 200 nm. For example, the thickness of the second electrode can be 150 nm.

[0369] The second electrode is typically disposed on the third region by vapor deposition. In many cases, the step of forming the second electrode includes installing a film containing a hole transport material in a thermal evaporation apparatus. Typically, the step of forming the second electrode includes depositing the second electrode through a shadow mask under high vacuum. Typically, the vacuum is 10 -4 Pa (10 -6 mBar).

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

[0371] Alternatively, the process of the present invention for manufacturing an optoelectronic device can be a process for manufacturing an inverted optoelectronic device.

[0372] Therefore, the present invention provides a process for manufacturing an inverted optoelectronic device including a photoactive region, the photoactive region including an n-type region including at least one n-type layer, a p-type region including at least one p-type layer, and a layer of perovskite semiconductor without open pores disposed between the n-type region and the p-type region, and the process includes (a) providing a first region, (a) providing a first region, (b) Placing a second region over the first region, the second region including a layer of perovskite semiconductor without open pores, and (c) Placing a third region over the second region, including, where the first region is a p-type region including at least one p-type layer, the third region is an n-type region including at least one n-type layer, and the first region is placed over the first electrode.

[0373] Typically, the first electrode includes a transparent or translucent material. Typically, the first electrode includes a transparent conductive oxide, such as FTO, ITO, or AZO. Preferably, the first electrode includes FTO. The first electrode can be placed over a glass substrate.

[0374] Each of the steps in the process for manufacturing an inverted optoelectronic device can be as defined anywhere herein with respect to the process according to the present invention for manufacturing an optoelectronic device. Each of the components used or present in this process can be as defined with respect to the optoelectronic device according to the present invention.

[0375] The first region, which is a p-type region, can be as defined anywhere herein with respect to the p-type region. In many cases, the first region includes a layer of PEDOT:PSS. Crosslinking can be performed to insolubilize the p-type region, so that even if the deposition process might dissolve the p-type layer, the p-type region does not dissolve even partially during the deposition of the second region. Sometimes, therefore, the layer of PEDOT:PSS includes crosslinked PEDOT:PSS. Crosslinking can be performed using a metal cation such as a Lewis acid, e.g., Fe 3+ or Mg 2+ etc. For example, (a) is (i) providing a first region including a layer of PEDOT:PSS, and (ii) treating the layer with an aqueous solution of FeCl3 to produce a layer of PEDOT:PSS including crosslinked PEDOT:PSS, can include.

[0376] A second region that is an n-type region can be made as defined somewhere herein with respect to the n-type region. In many cases, the n-type region includes a dense layer of an inorganic n-type semiconductor, such as defined herein. Typically, the n-type region includes a dense layer of titanium dioxide. In some embodiments, the n-type region further includes a layer of

[60] PCBM.

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

[60] PCBM over the second region, and (ii) disposing a dense layer of titanium dioxide over the layer of

[60] PCBM, including.

[0378] In an inverter device, the second electrode can be disposed over a third region that is an n-type region. Thus, the process can further include (d) disposing the second electrode over the third region, including.

[0379] The second electrode can be placed directly on top of the third region or there may be an additional layer that is inverted. Typically, the second electrode is in contact with the third region. The second electrode can be as defined anywhere herein and typically includes a metal. For example, the second electrode can include aluminum, gold, silver, nickel, palladium, or platinum, typically aluminum, silver, or gold. In one embodiment, the second electrode includes silver, gold, or aluminum. For example, if the n-type region includes a dense layer of titanium and a layer of

[60] PCBM, the second electrode can include aluminum. Although the second electrode can typically be deposited by any technique such as those described herein, it is typically placed by vacuum deposition. Thus, the second electrode can be placed 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 (d) placing a tunnel junction on top of the third region, (e) placing an additional photoactive region on top of the tunnel junction, which can be the same as or different from the photoactive regions previously defined herein, (f) optionally repeating steps (d) and (e), and (g) placing a second electrode on top of the additional photoactive region placed in the previous step, further includes.

[0380] In a process for manufacturing a tandem junction or multi-junction device according to the present invention, the additional photoactive region can be as defined anywhere herein previously with respect to the tandem optoelectronic device according to the present invention. In particular, the additional photoactive region can include a layer of crystalline silicon or can include a thin film of CIGS, CIS, or CZTSSe.

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

[0382] In the process of the present invention for manufacturing an optoelectronic device, the optoelectronic device can be made as further defined hereinbefore with respect to the optoelectronic device of the present invention.

[0383] The present invention further provides an optoelectronic device that can be obtained by the process of the present invention for manufacturing an optoelectronic device.

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

[0385] Example Experimental method for device preparation Preparation of Al2O3 paste with polymer binder An aluminum oxide dispersion was purchased from Sigma-Aldrich (10 wt% in water) and washed by the following method: The dispersion was centrifuged at 7500 rpm for 6 hours and redispersed in absolute ethanol (Fisher Chemicals) using an ultrasonic probe: The ultrasonic probe was operated at a cycle of 2 seconds on and 2 seconds off for a total ultrasonic treatment time of 5 minutes. This process was repeated 3 times.

[0386] For every 10 g of the original dispersion (total 1 g of Al2O3), the following were added: 3.33 g of α-terpineol in ethanol at 10% by weight and 5 g of a 50:50 mixture of ethyl cellulose 10 cP and 46 cP purchased from Sigma Aldrich. After the addition of each component, the mixture was stirred for 2 minutes and sonicated using an ultrasonic probe at a cycle of 2 seconds on and 2 seconds off for a sonicating time of 1 minute. Finally, the resulting mixture was introduced into a rotary evaporator to remove the excess ethanol and achieve the thickness required for doctor blading, spin coating or screen printing.

[0387] Preparation of TiO2 paste with polymer binder A titanium dioxide dispersion (DSL 18NR-T) containing a polymer binder was purchased from Dyesol. This dispersion was diluted with absolute ethanol (Fisher Chemicals) at a weight ratio of 3:1 of absolute ethanol:DSL 18NR-T using an ultrasonic probe; the ultrasonic probe was operated at a cycle of 2 seconds on and 2 seconds off for a total ultrasonic treatment time of 5 minutes.

[0388] Preparation of Al2O3 paste without polymer binder An aluminum oxide dispersion was purchased from Sigma-Aldrich (20% by weight in isopropanol). This was diluted to 16 volume equivalents of isopropanol.

[0389] Preparation of TiO2 paste without polymer binder Titanium dioxide powder (P25) was purchased from (Degussa) and dispersed in ethanol at 20 mg / ml. This was diluted to 16 volume equivalents of ethanol.

[0390] Preparation of methylammonium iodide precursor and perovskite precursor solution A 33 wt% solution of methylamine (CH3NH2) in absolute ethanol (Sigma-Aldrich) was reacted with 57 wt% hydroiodic acid (Sigma-Aldrich) in water at 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. Crystallization of methylammonium iodide (CHNH3I) was obtained using a rotary evaporator. A white precipitate showing good crystallization was formed.

[0391] Subsequently, in order to change the perovskite properties, it is possible to substitute methylamine with other amines such as ethylamine, n-butylamine, tertiary butylamine, octylamine, etc. In addition, in order to form another perovskite, it is possible to substitute hydroiodic acid with other acids such as hydrochloric acid.

[0392] To prepare the precursor solution, methylammonium iodide (CH₃NH₃I) precipitate and lead(II) chloride (Sigma - Aldrich) were dissolved in dimethylformamide (C₃H₇NO) (Sigma - Aldrich) at 30 vol% with a 1:1 molar ratio.

[0393] Cleaning and Etching of the Substrate and Transparent Electrode A glass sheet (TEC 15, 15 Ω / square, Pilkington USA) coated with fluorine - doped tin oxide (F:SnO₂ / FTO) was etched using 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 minutes to remove all organic residues.

[0394] Deposition of a Dense TiO₂ Layer The patterned FTO sheet was then coated with a dense layer of TiO₂ by spin - coating with a weakly acidic titanium isopropoxide (Sigma - Aldrich) sol in ethanol. The sol was prepared by mixing titanium isopropoxide:anhydrous ethanol at a weight ratio of 0.71:4 with an acidic solution of 2M HCl:anhydrous ethanol at a weight ratio of 0.07:4. After spin - coating (speed = 2000 rpm, acceleration = 2000 rpm / s, time = 60 s), the substrate was dried on a hot plate at 150 °C for 10 minutes. Optionally, the dense layer was then heated to 500 °C on a hot plate in air for 30 minutes.

[0395] Deposition of a Thin Mesoporous Metal Oxide Layer An insulating metal oxide paste (e.g., Al2O3 paste) was applied onto the upper surface of the dense metal oxide layer by screen printing, doctor blade coating or spin coating via an appropriate mesh, doctor blade height or spin speed to form a film having a thickness of about 100 nm. The film was then heated to 500 °C and held there for 30 minutes (high temperature sintering) to decompose and remove any polymer binder, or when there is no 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 40 μl of a perovskite precursor solution in 30% volume concentration of dimethylformamide (methylammonium lead(II) iodide chloride (CH3NH3PbCl2I)) was dispensed onto each of the prepared mesoporous electrode films and spin-coated at 1500 rpm for 60 s in an inert nitrogen environment. Before cooling, the coated film was placed on a hot plate set at 100 °C and left in nitrogen for 60 minutes. During the drying procedure at 100 degrees, the coated electrode changed color from bright yellow to dark brown, indicating the formation of the desired perovskite film with semiconducting properties.

[0397] Vapor Deposition of Perovskite Precursors and Formation of Semiconducting Perovskite Thin Films PbI2 and CH3NH3Cl in a 1:1 molar ratio were ground using a pestle and mortar for 15 minutes to form a bulk perovskite powder. This formed a powder that was dried in a nitrogen environment for > 12 hours (more than 12 hours). The crucible containing the perovskite powder was then transferred to an evacuated vapor deposition chamber. The crucible was slowly heated to 300 °C. When the source temperature reached 100 °C, the shutter was opened to begin deposition onto the substrate. The heater was periodically switched off to maintain a pressure of 10 -2 Pa (10 -4The pressure of (mbar) was maintained. Evaporation was continued until a thin film of approximately 100 - 300 nm was deposited onto the substrate. Subsequently, the substrate with the deposited material was heated to 50 °C for 1 hour in a nitrogen environment.

[0398] Preparation of Perovskite Containing Formamidinium Cation As an alternative to ammonium ions, formamidinium cations can be used. Formamidinium iodide (FOI: formamidinium iodide) and formamidinium bromide (FOBr: formamidinium bromide) were synthesized by reacting a 0.5 M solution of formamidinium acetate in ethanol with 3x molar excess of hydroiodic acid (for FOI) or hydrobromic acid (for FOBr). The acid was added dropwise while stirring at room temperature, and then stirring was continued for another 10 minutes. Drying at 100 °C formed a yellowish - white powder, which was then dried overnight in a vacuum oven before use. To form the FOPbI3 and FOPbBr3 precursor solutions, FOI and PbI2 or FOBr and PbBr2 were dissolved in anhydrous N,N - dimethylformamide at a molar ratio of 1:1 at 0.88 millimoles per ml, producing a 0.88 M perovskite precursor solution. FOPbI 3z Br 3(1-z) To form the perovskite precursor, the mixture was made from 0.88 M solutions of FOPbI3 and FOPbBr3 in the required ratio, 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 minutes in a nitrogen atmosphere.

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

[0400] Element variants studied A general schematic diagram of the device structure is shown in Fig. 1a. This device can be placed on any solid substrate material (glass, plastic, metal foil, metal mesh, etc.). In Fig. 1a, at least one of the metal electrodes must be transparent / translucent (e.g., doped or undoped metal oxide, perovskite, polymer, thin metal, metal mesh, etc.), while the opposite electrode can be made transparent / translucent or reflective. A light-absorbing perovskite that can be n-type, p-type or intrinsic is sandwiched between one n-type semiconducting layer and one p-type semiconducting layer (organic, inorganic, amorphous Si, perovskite, hybrid organic / inorganic, etc.) for selective electron extraction and hole extraction respectively. It is possible to invert the structure shown. A multi-junction cell can be fabricated by stacking repetitive structures.

[0401] Certain embodiments of the device of the present invention have the specific structure shown in FIG. 1b. When used, the thin metal oxide layer is generally permeable to solution-processed perovskites and ensures direct contact with the perovskite having an electron-selective contact. Each of the preparatory variations considered here is summarized in Table 1.

[0402] [Table 1]

[0403] Results and Discussion Pore Size Control of Mesoporous Al2O3 Sintered at Low Temperature It is possible to control the porosity of the mesoporous layer of Al2O3 by mixing two solvents having different viscosities and different evaporation rates in the nanoparticle dispersion. After deposition from the dispersion and solvent removal, the refractive indices of the mesoporous synthetic thin film of Al2O3 and air depend on the volume fraction of the two components, i.e., the porosity. The refractive indices of the films formed by spin coating a dispersion having variable contents of terpineol and t-butanol onto a glass slide are shown in Table 2 below expressed as volume equivalents. The lower the refractive index, the larger the volume fraction of air, i.e., the more porous the film. In general, it has been found that adding a co-solvent increases the porosity of the resulting mesoporous film.

[0404] [Table 2]

[0405] X-ray Diffraction The XRD patterns of the perovskite thin films based on different underlying deformation examples studied are shown in Fig. 2a. All samples were prepared on bare glass, where a thin mesoporous oxide without a dense layer was identified. The two 110 and 220 perovskite peaks are prominent and consistent with our previous demonstration of this perovskite [Lee et al., Science, Submitted 2012]. Fig. 2b shows the XRD pattern of the perovskite when deposited. Peaks corresponding to the mixed halide perovskite are present in addition to the peaks arising from PbI2.

[0406] UV-visible spectroscopy The UV-visible patterns for the perovskite thin films based on different underlying deformation examples studied are shown in Fig. 3. All samples were prepared on bare glass, where a thin mesoporous oxide without a dense layer was identified. The spectra show the normalized absorbance (ε = log 10 [I0 / I1]). All spectra showed absorption onset at a wavelength of ~800 nm to confirm the presence of the perovskite. XRD diffraction peaks corresponding to PbI2 were observed for the deposited perovskite, but the UV-visible spectra indicate that most of the light is absorbed by the perovskite. The shape of the spectra is consistent with our previous demonstration of this perovskite [Lee et al., Science, Submitted 2012].

[0407] Current-voltage characteristics The current density-voltage (J-V) characteristics of several devices representative of each deformation example studied are shown in Fig. 4. A summary of the parameters extracted from these results is shown in Table 3. The thickness (t mesoporous ) of the thin oxide layer as measured using a surface profilometer and the thickness (t perovskite cap)It was also shown in Table 3. Regarding the thickness measurement, the sample was 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 that 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 FIGS. 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 FIGS. 6(a) to 6(f) and FIGS. 7(a) and 7(b). When Al2O3 is used with and without a binder and sintered at both high and low temperatures, the images clearly show that the mesoporous structure enables the penetration and seeding of the perovskite. The dense layers shown in FIGS. 6(e) and 6(f) appear featureless at the resolution of the instrument. When using TiO2, with a binder, the film appears mesoporous. However, without a binder, the nanoparticles aggregate and form sub-monolayers.

[0410] Conclusion The examples show that it is possible to fabricate optoelectronic devices with a flat n-type / perovskite absorber / p-type structure. The growth of the perovskite light absorber was achieved from solution deposition onto a thin scaffold or without a scaffold. Devices incorporating a thin seed layer can be processed at temperatures not exceeding 150 °C, which is important for flexible and / or tandem / multijunction devices. In addition, it was shown that the perovskite can be formed by evaporation from bulk powder.

[0411] Inverted heterojunction perovskite solar cell Substrate preparation A glass sheet (7 Ω / square Pilkington) coated with fluorine-doped tin oxide (FTO) was etched with zinc powder and HCl (2 mol) to obtain the required electrode pattern. The sheet was then washed with a detergent (2% Hellmanex in water), deionized water, acetone, methanol, and finally treated under oxygen plasma for 5 minutes to remove the last trace amounts of organic residues.

[0412] TiO x Planar film precursor solution: TiO x The planar film 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 at 0.46 M. Separately, 2 M HCl solution was diluted with ethanol until a concentration of 0.026 M was achieved. Finally, the acidic solution was added dropwise to the titanium precursor solution while stirring vigorously.

[0413] Normal architecture fabrication: The etched FTO substrate was spin-coated with TiO at 2000 rpm for 60 s xA planar film precursor solution was spin-coated and then coated with a dense layer of TiO2 deposited by heating at 500 °C for 30 minutes, forming anatase titania of stoichiometric composition. Next, a colloidal dispersion of approximately 20 nm Al2O3 nanoparticles in isopropanol was spin-coated, and then a mesoporous scaffold was deposited by drying at 150 °C for 10 minutes. After cooling to room temperature, perovskite was deposited by spin-coating from a DMF solution of methylammonium iodide and PbCl2 (3:1 molar ratio), which formed perovskite after heating at 100 °C for 45 minutes. A 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 a chlorobenzene solution containing 80 mM tert-butylpyridine (tBP) and 25 mM lithium bis(trifluoromethanesulfonyl)imide (LITFSI) at 1000 rpm for 45 s. Finally, the device was completed by evaporation of Ag contact electrodes through a shadow mask in high vacuum.

[0414] Inverted architecture fabrication: PEDOT:PSS: PEDOT:PSS (Clevios): A 25:75 vol% solution of PEDOT:PSS in isopropanol (>99.9%, Fisher Chemicals) was spin-coated onto an etched FTO substrate at 2000 rpm for 60 s, then annealed at 150 °C for 20 minutes or cross-linked by immersing the substrate in 0.25 M aqueous FeCl3 solution for 5 minutes, then washed in two consecutive baths of deionized water and finally dried with nitrogen.

[0415] NiO: Both nickel acetate tetrahydrate and monomethanolamine at a concentration of 0.1 M were dissolved by stirring in ethanol in a sealed vial on a hot plate at 70 °C for 4 hours in air to prepare a spin-coating precursor for the NiO thin film. The solution was homogeneous and appeared dark green.

[0416] V2O5: An etched FTO substrate was coated with a thin film of V2O5 deposited by spin-coating a 1:35 volume % solution of vanadium(V) oxytris(isopropoxide) (Sigma Aldrich) in isopropanol, and then heated to 500 °C to obtain a crystalline vanadium oxide layer.

[0417] Perovskite and n-type contact deposition: After cooling / drying, the perovskite precursor solution was spin-coated at 2000 rpm for 20 s and then heated to 100 °C for 45 min to form the structure. A 20 mg mL -1 solution of

[60] PCBM in chlorobenzene (anhydrous, Sigma Aldrich) was spin-coated at 1000 rpm for 45 s to deposit an electron-selective contact. 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 evaporation of the Al contact electrodes in high vacuum through a shadow mask.

[0418] Results and discussion Perovskite thin-film photovoltaic devices have recently been reported, having an architecture developed from solid-state dye-sensitized solar cells that collect holes through a metal cathode and electrons through an FTO anode (Ball, J. M.; Lee, M. M.; Hey, A.; Snaith, H. Low-Temperature Processed Mesosuperstructured to Thin-Film Perovskite Solar Cells, Energy & Environmental Science 2013). In this configuration, a thin film of mesoporous alumina is deposited over an FTO substrate covered with dense TiO2 to assist in the formation of the perovskite film, and then an organic hole transporter is deposited over the formed structure to provide a hole-selective contact. However, since holes are collected through the upper metal cathode, this configuration is limited in its use in tandem solar cells, and it is possible to achieve immediate improvement by using a "wide-bandgap" perovskite containing an inorganic lower cell with a small bandgap (Beiley, Z. M.; McGehee, M. D. Modeling low cost hybrid tandem photovoltaics with the potential for efficiencies exceeding 20%, Energy & Environmental Science 2012, 5, 9173-9179), which is generally fabricated in a "substrate" configuration where electrons are collected at the upper metal contact.

[0419] Typical materials used in organic photovoltaics as hole-selective contacts for blend materials are PEDOT:PSS, V2O5, and NiO, while usually, 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 function in the completed device, an excellent first step to check whether charge transfer to these intermediate layers is possible is, as is standard in all organic solar cells, to measure the steady-state PL quenching efficiency. This data is shown in Fig. 9 and the results are summarized in Table 4. It is clearly seen that all p-type layers selected in this study quench perovskite PL more efficiently than the model spiro-OMeTAD system, having similar values for PEDOT:PSS and V2O5 with a quenching efficiency of 99.87%. All n-type layers showed a significantly higher quenching rate than the model TiO2 system which shows only 45% steady-state quenching efficiency. Since solar cells fabricated using the PFN intermediate layer resulted in extremely poor optoelectronic performance, all cells fabricated in this study had PC spin-coated as the n-type contact 60 utilize the BM layer.

[0420]

Table 4

[0421] PEDOT:PSS as the p-type contact The first example of an inverted architecture using perovskite as both a light absorber and a charge transporter is a thin PEDOT:PSS layer as the p-type contact and PC as the n-type contact 60 utilize the BM and a dense TiO x double layer. To enable processing of these structures in air, TiO xThe upper intermediate layer was necessary to achieve good contact with the upper Al anode. A cross-sectional SEM photograph of the optimized structure is shown in Fig. 10. Uniform coverage of the perovskite structure is essential for fabricating an optimal optoelectronic device and is strongly affected by the substrate on which the device is formed. As shown in Figs. 11b) and 11d), when assembled on top of the annealed PEDOT:PSS lower layer, macro-crystals with a perovskite length exceeding 30 μm are formed. This should be advantageous for charge transport through the layer, but rather large micron-sized gaps exist between the crystals, which is not favorable for device performance PC 60 allows direct contact between the 60

[0422] PCBM and the PEDOT:PSS lower layer. PEDOT:PSS is soluble in DMF, and for this reason, when depositing the perovskite precursor in DMF, PEDOT:PSS is crosslinked by immersing it in an aqueous 0.25 M FeCl3 solution to avoid redissolution of the layer. When PEDOT:PSS is crosslinked, surprisingly, the resulting perovskite film coverage increases significantly, although the average crystal size / feature size for this material decreases considerably. The resulting coverage and crystal size are shown in Figs. 11a) and 11c), and were directly estimated from the SEM images, finding that they are 80 ± 1% for the annealed PEDOT:PSS film and 97 ± 1% for the crosslinked film. -2 When comparing the performance of the resulting devices, as shown in Fig. 12a), it was found that the devices processed on crosslinked PEDOT:PSS exhibit an open-circuit voltage of around 0.8 V, while the devices on annealed PEDOT:PSS only achieve about 0.64 V. This is consistent with a decrease in charge recombination between the charges in the PCBM layer and the charges in the PEDOT:PSS layer due to the improvement in perovskite film coverage. The devices employing crosslinked PEDOT:PSS show 16.2 mAcm -2 compared to 17.2 mAcm for the annealed PEDOT:PSS devicesshows a slightly decreased short - circuit current, but the difference is small and within the range of experimental variation. Finally, the power conversion efficiency of the optimized device reaches a value exceeding 6.7%, far exceeding the performance of the annealed PEDOT:PSS device that reaches 5.6%.

[0423] V2O5 and NiO as p - type contacts Both V2O5 and NiO are the normal p - type materials currently used for highly efficient and stable organic optoelectronic devices. Here, the inventors fabricated the device by spin - coating an appropriate precursor solution on FTO, having a subsequent sintering step at 500 °C to ensure a complete - crystal metal oxide layer. As can be seen in the SEM photograph of Figure 13, the surface coverage of the perovskite solution can be a problem with this material.

[0424] The optoelectronic performance of the device incorporating these layers is shown in Figure 14.

[0425] Comparison with the normal architecture Finally, compare the champion inverted device incorporating PEDOT:PSS as the hole - accepting layer and PC 60 BM as the electron - extraction layer with a normal - architecture device composed of TiO2 as the electron - accepting layer and spiro - OMeTAD as the hole - transporting layer in Figure 15b). Both methods achieve a surprising short - circuit current exceeding 17.5 mA / cm² and a high open - circuit voltage exceeding 0.9 V. The main difference in the power conversion efficiency of 11.8% for the normal architecture and 7.54% for the inverted device is the lower fill factor of the latter. This is probably due to either the leakage problem between PEDOT:PSS and PCBM as shown in Figure 5.a. or series - resistance losses, probably due to the necessity of using a TiO -2 overlay. x to be able to process the device under ambient air conditions.

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

[0427] Conclusion An inverted device structure where holes are collected through FTO is necessary for tandem applications using inorganic photovoltaic bottom cells. Here, we show low-temperature, ambient air, and solution-processable photovoltaic cells based on semiconducting perovskite absorbers and selective n-type and p-type contacts in the form of PEDOT:PSS and

[60] PCBM. A power conversion efficiency of 7.5% was realized 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 barriers to the application of perovskite technology by the organic photovoltaic community.

[0428] 2 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 milliQ water, then washed with a 2% solution of Hellmanex diluted in milliQ water, rinsed with milliQ water, acetone, and ethanol, and dried with clean dry air. It was then treated with oxygen plasma for 10 minutes. A dense layer of TiO2 was spin-coated with 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 was a dual-source evaporation method that could successfully manage the organic source and the inorganic source separately. The evaporation device was a Kurt J. Lesker Mini Spectros Deposition System (Figure 18) with a ceramic crucible (OLED source) stored in a dry glove box filled with nitrogen. Therefore, all processes were carried out in an oxygen-free environment. The working chamber was designed to operate under a pressure of 5E-4 Pa (5E-6 mbar) where vapor particles could move directly to the substrate. The sample was held with its surface down in a holder above the crucible containing the source powder. Two crystal sensor monitors were installed just 10 cm above the crucible to separately monitor the deposition rate of each source without interfering with each other. These measured values were used as feedback to adjust the heating temperature of the source chemicals. Another crystal sensor that could be used to measure the total deposition thickness was available near the substrate holder.

[0430] Touring factor measurement Since the distance from the source to the monitor was different from the distance from the source to the substrate, the touring factor (the ratio of the material deposited on the sensor to the material deposited on the sample) of each source was calibrated separately. The density of CH3NH3I was assumed to be 1 g / cm 3 as it was not available. The set values and results are shown in Table 5.

[0431]

Table 5

[0432] Note that due to the instability of the organic source CH3NH3I during the evaporation process, it is difficult to deposit the organic source steadily, and its deposition rate has variations from the set value by up to + / - 20%. The physical thickness was measured by a Veeco DekTak 150 film thickness probe.

[0433] Dual-Source Perovskite Deposition The inventors aimed to investigate "planar heterojunction" perovskite solar cells by vapor deposition within a dual-source deposition system. The evaporated perovskite can be deposited directly onto the upper surface of a dense layer of TiO2 without a mesoporous layer (Figures 20b and 20c).

[0434] The organic source CH3NH3I and the inorganic source PbCl2 were weighed at approximately 200 mg and 100 mg, respectively, and loaded into two crucibles. The samples were inserted into the substrate holder with the surface facing down. Once the pressure inside the chamber was evacuated to 5E-4 Pa (5E-6 mbar), the shutters of the two OLED sources were opened while heating the sources. Once the two sources reached the set values, the holder was rotated to open the shutter of the substrate in order to obtain a uniform thin film.

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

[0436] When comparing the deposited perovskite with the conventionally spin-coated perovskite, the deposited perovskite has a more uniform and flat surface with fewer holes (Figure 21). Sufficient coverage of the deposited perovskite not only makes good contact with the dense layer of TiO2 but also separates the hole transport layer from the dense layer. This will surely contribute to the photocurrent and voltage throughout the system.

[0437] Element property evaluation The experiment was started by changing the composition of CH3NH3I to PbCl2 from 4:1 to 16:1 in molar ratio under a constant total thickness. Once the composition was optimized, the desired thickness under the optimal composition was considered.

[0438] The highest performance was achieved by setting the deposition rate to 5.3 Å / s for CH3NH3I and 1 Å / s for PbCl2, realizing a power conversion efficiency of 13%, which should ideally give a molar ratio of 9.3:1 considering the tooling factor. However, as described above, since the deposition of the organic source CH3NH3I always has fluctuations, the final thickness shown in sensor 1 for CH3NH3I was 44.4 kÅ instead of the expected 42.4 kÅ. In other words, the actual average deposition rate for CH3NH3I should be rather 5.6 Å / s than the set value of 5.3 Å / s. In this case, the film was actually deposited under a molar ratio of 9.8:1 of CH3NH3I to PbCl2, which gave a physical thickness of 230 nm measured by a dectack probe.

[0439] The highest performance gave a short-circuit photocurrent J 2 of 21.47 mA / cm sc , an open-circuit voltage V oc of 1.07 volts, and a fill factor (FF) of 0.67, resulting in a power conversion efficiency up to 15.36%. Under artificial AM1.5G sunlight at an illuminance of 100 mW·cm -2 , the current-voltage characteristics were measured (2400 series SourceMeter, Keithley Instruments), and the solar cell was masked with a metal aperture to define the active area, which is typically 0.076 cm 2 , and measured in a light-tight sample holder to minimize all edge effects.

[0440] To define the content in the evaporated film, the XRD pattern of the surface of the evaporated perovskite was measured and then compared to the conventional XRD pattern of the spin-coated perovskite and other essential chemical substances as shown in FIG. 23. According to the XRD pattern, it was clearly shown that the evaporated perovskite is almost the same as the solution-processed perovskite film (named K330) treated from CH3NH3I and PbCl2 precursors in DMF, which indicates that the evaporated perovskite has the same crystal structure as the spin-coated perovskite.

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

[0442] Conclusion Here, it was demonstrated that an evaporated hybrid inorganic-organic perovskite for planar junction solar cells with a power conversion efficiency exceeding 15% can be achieved by appropriately controlling the deposition rates of CH3NH3I and PbCl2 and the deposition thickness on the substrate. Realizing the use of evaporation technology to manufacture perovskite solar cells overcomes the limitations of the solution process of finding a suitable solution for dissolving chemicals and thus also serves for the commercialization of hybrid inorganic-organic solar cells.

[0443] In general, contrary to creating layered perovskites that inevitably have a large exciton binding energy, it is considered advantageous to maintain the 3D crystal structure in perovskites (Journal of Luminescence 60&61 (1994) 269 274). It is also, of course, advantageous that the band gap of the perovskite can be adjusted. By changing either the metal cation or the halide that directly affects both the electron orbitals and the crystal structure, it is possible to change the band gap. Alternatively, it is possible to change the crystal structure by changing the organic cation (e.g., from methylammonium cation to formamidinium cation). However, in order to fit within the perovskite crystal, the following geometric conditions must be satisfied:

Number

[0444] Two-step perovskite layer fabrication Substrate preparation An electrode pattern was etched on a fluorine-doped tin oxide-coated glass substrate (FTO, TEC7 Pilkington Glass) using a mixture of Zn powder and 2M HCl. These were then sequentially washed in Hallmanex, deionized water, acetone, propan-2-ol, and O2 plasma.

[0445] Electron-selective layer deposition A thin (approximately 50 nm) layer of TiO2 acts as an electron-selective layer. A thin layer of TiO2 was deposited onto a 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 containing added HCl. These films were heated at 500 °C for 30 minutes.

[0446] Deposition of PbI2 and PbCl2 At a rate of approximately 2 Å / s at a pressure of approximately 10 -4 Pa (10 -6 mbar), thin films (approximately 150 nm) of PbI2 and PbCl2 were deposited by thermal evaporation onto the substrate through a shadow mask. The evaporation temperatures were approximately 270 °C and 310 °C for PbI2 and PbCl2, respectively.

[0447] Dip-coating perovskite conversion For dip-coating, substrates pre-coated in PbI2 or PbCl2 were immersed into a 20 mg / ml solution of methylammonium iodide in anhydrous propan-2-ol within a nitrogen-filled glove box. The immersion time was constant at 10 minutes for all devices. After dip-coating, the substrates were annealed at 120 °C in a nitrogen atmosphere for 10 minutes. The immersion time may range from 10 seconds to 2 hours. For the examples given in this patent, the immersion time was 10 minutes.

[0448] Hole transport material deposition In a nitrogen-filled glove box, 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.

[0449] Upper electrode deposition The upper silver electrode was deposited by thermal evaporation (at a pressure of approximately 6.7×10 -4 Pa (5 μTorr)) at a rate of approximately 2 Å / s to a thickness of 150 nm.

[0450] Device current-voltage characteristic evaluation To measure the performance of the solar cell, an artificial AM1.5 sunlight was generated using a calibrated class AAB ABET artificial solar light source to provide an equivalent irradiance of 106.5 mW / cm 2 in order to give an artificial AM1.5 of equivalent irradiance. The mismatch factor was calculated to be 1.065 between 300 and 900 nm, which exceeds the operating range of both the KG5 filter-treated silicon reference cell and the perovskite test cell. The current-voltage curve was recorded using a source meter (Keithley 2400, USA). The solar cell was masked using a metal aperture that defines the active area (0.0625 cm 2 ) of the solar cell. The current density-voltage characteristics of the device are shown in Fig. 32 (for PbI2 (dashed line) as the photoactive layer and CH3NH3PbI3 (solid line) after dip coating as the photoactive layer), and Fig. 33 (for PbCl2 (dashed line) as the photoactive layer and CH3NH3PbI 3-x Cl x (solid line) as the photoactive layer).

[0451] X-ray diffraction An X-ray diffraction (XRD) spectrum was obtained from a device without a silver electrode (FTO-coated glass, TiO2, photoactive layer, spiro-OMeTAD) using a PANalytical X’Pert Pro X-ray diffractometer. The results are shown in Fig. 31.

[0452] Scanning electron microscope observation Using a Hitachi S-4300, a scanning electron microscopy (SEM) image was obtained from an element without a silver electrode (FTO-coated glass, TiO2, photoactive layer, Spiro-OMeTAD). The electron micrographs are shown in Fig. 29 ((a) PbCl2 and (b) CH3NH3PbI after dip coating 3-x Cl x for), and Fig. 30 ((a) PbI2 and (b) CH3NH3PbI3 after dip coating for).

[0453] Results and Discussion The two-step method enables the production of a uniform perovskite film using an economic technique already readily available in the glazing industry. After the initial deposition of the metal dihalide, a uniform and flat perovskite film can be produced by the penetration of the metal dihalide with the organic halide. Fig. 31 shows the X-ray diffraction spectra of thin films of (a) PbCl2, (b) CH3NH3PbI 3-x Cl x , (c) PbI2, and (d) CH3NH3PbI3. 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 a significant conversion of the precursor film to perovskite.

[0454] Fig. 29 shows cross-sectional scanning electron micrographs of an element showing, from bottom to top, a glass substrate, FTO, TiO2 electron-selective layer, photoactive layer, Spiro-OMeTAD. The photoactive layer is (a) PbCl2 and (b) CH3NH3PbI 3-x Cl x after dip coating. Fig. 30 shows cross-sectional scanning electron micrographs of an element showing, from bottom to top, a glass substrate, FTO, TiO2 electron-selective layer, photoactive layer, Spiro-OMeTAD. The photoactive layer is (a) PbI2 and (b) CH3NH3PbI3 after dip coating. In both cases, the perovskite produced by dip coating shows relative uniformity.

[0455] The current density-voltage characteristics of the device are shown in FIGS. 32 and 33. In FIG. 32, the characteristics are shown for a device made using PbI2 as the active layer (dashed line) and a device in which vapor-deposited PbI2 is converted to CH3NH3PbI3 by immersion coating in a solution of methylammonium iodide in propan-2-ol (solid line). The performance parameters for PbI2 are J sc = 1.6 mA / cm 2 , PCE = 0.80%, V oc = 0.97 V, FF = 0.57. The performance parameters for CH3NH3PbI3 are J sc = 5.3 mA / cm 2 , PCE = 2.4%, V oc = 0.82 V, FF = 0.61. In FIG. 33, the current density-voltage characteristics are shown for a device made using PbCl2 as the active layer (dashed line) and a device in which vapor-deposited PbCl2 is converted to CH3NH3PbI 3-x Cl x by immersion coating in a solution of methylammonium iodide in propan-2-ol (solid line). The performance parameters for PbCl2 are J sc = 0.081 mA / cm 2 , PCE = 0.006%, V oc = 0.29 V, FF = 0.27. The performance parameters for CH3NH3PbI 3-x Cl x are J sc = 19.0 mA / cm 2 , PCE = 7.0%, V oc = 0.8 V, FF = 0.49. In both cases, it was shown that a viable device is fabricated by this two-step method.

[0456] Estimation of Charge Carrier Diffusion Length Regarding charges (either electrons or holes) generated from optical absorption and efficiently collected from a thin solid film, the lifetime of the charge species (the time the charge species survives before recombining with the oppositely charged species) must be longer than the time it takes to diffuse across the film and flow into the electrodes. The diffusion coefficient (De) and the lifetime (τe ) with the following diffusion length (L D )

Number

[0457] To determine the diffusion length of photoexcited bound electron-hole pairs (excitons), photoluminescence (PL) quenching has been successfully utilized previously in organic semiconductors. By simply fabricating a solid thin film with or without an exciton quenching layer and modeling the photoluminescence decay in the 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 Fig. 36.

[0458] Model the PL decay dynamics by calculating the number and distribution n(x,t) of excitations in the film according to the 1-D diffusion equation (Equation 1),

Number

Number

[0459]

Table 6

[0460] Triiodide perovskite (CH3NH3PbI3) and mixed halide perovskite (CH3NH3PbI 3-x Cl x ) are compared in FIG. 37, which shows the photoluminescence decay for a mixed halide organolead trihalide perovskite film CH3NH3PbI 3-x Cl x (black squares) and an organolead triiodide perovskite film CH3NH3PbI3 (gray squares) coated with PMMA. The lifetime τ e was estimated as the time taken to reach 1 / e of the initial intensity.

[0461] Surprisingly, the diffusion lengths for both electrons and holes in the mixed halide perovskite are greater than 1 μm, which is significantly longer than the absorption depth of 100 to 200 nm. This indicates that a mesostructure or nanostructure with this specific perovskite absorber should not be required. The triiodide perovskite CH3NH3PbI3 film has a short diffusion length of around 100 nm for both electrons and holes. The large diffusion length of the mixed halide perovskite enables the fabrication of a photovoltaic device with a perovskite layer having a thickness exceeding 100 nm, which exhibits excellent device characteristics.

[0462] Method Perovskite precursor preparation: Methylamine iodide (MAI) was prepared by reacting 33 wt% methylamine in ethanol (Sigma-Aldrich) with 57 wt% hydroiodic acid (HI) in water at room temperature. HI was added dropwise with stirring. Drying at 100 °C formed a white powder, which was dried overnight in a vacuum oven and recrystallized from ethanol before use. CH3NH3PbI 3-x Cl x Alternatively, to form a CH3NH3PbI3 precursor solution, methylammonium iodide and lead(II) chloride (Sigma-Aldrich) or lead(II) iodide (Sigma-Aldrich) were dissolved in anhydrous N,N-dimethylformamide (DMF) at a 3:1 molar ratio of MAI to PbCl2 / PbI2, using a final concentration of 0.88 M lead chloride / lead iodide and 2.64 M methylammonium iodide.

[0463] Substrate preparation: Glass substrates for absorption, TA, and PL measurements were sequentially cleaned in 2% Hellmanex 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 the FTO with 2 M HCl and zinc powder to prevent shunting by contact with the measurement pins. The substrate was cleaned and plasma-etched as described above. A dense TiO2 hole-blocking layer was deposited by spin-coating a weakly acidic solution of titanium isopropoxide in ethanol 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 layer for spectroscopic measurement, a non-stoichiometric precursor was spin-coated onto the substrate at 2000 rpm in air. For CH3NH3PbI 3-x Cl x , the precursor was used as it was. For CH3NH3PbI3, the precursor was diluted in DMF at a 1:1 ratio of the precursor solution to DMF. After spin-coating, the CH3NH3PbI 3-x Cl x film was annealed at 100 °C for 45 minutes, and CH3NH3PbI3 was annealed at 150 °C for 15 minutes. Next, the top quencher was deposited in air via spin-coating of a chlorobenzene solution using the following conditions: 10 mg / ml of poly(methyl methacrylate) (PMMA; Sigma-Aldrich) and 30 mg / ml of phenyl-C61-butyric acid methyl ester (PCBM; Solenne BV), both spin-coated at 1000 rpm, and 0.46 M of 2,2’,7,7’-tetrakis-(N,N-di-p-methoxyphenylamine) 9,9’-spirobifluorene (Spiro-OMeTAD; Borun Chemicals) spin-coated at 2000 rpm.

[0465] Characteristic evaluation: To obtain SEM images, a field emission scanning electron microscope (Hitachi S-4300) was used. The sample thickness was measured using a Beeco DekTak 150 surface profilometer.

[0466] Photoluminescence measurements and fitting: Steady-state and time-resolved PL measurements were obtained using a time-correlated single photon counting (TCSPC) apparatus (FluoTime 300, PicoQuant GmbH). A 117 ps pulse duration and ~30 nJ / cm 2Using the fluence of , pulsed at a frequency between 0.3 and 10 MHz, and a 507 nm laser head (LDH-P-C-510, PicoQuant GmbH), the film sample was optically excited. 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 when there is no quenching material need to be input into the diffusion model. In the form of an extended exponential decay function,

Equation

[0468] The reduced χ obtained by independently varying each fitting parameter 2 By examining the surface, the error in the fitting parameters was determined. To obtain the limit at a 68% confidence level, χ R 2 (p) / χ R 2 = 1.2 cutoff values were used in each case. To facilitate the comparison of lifetimes between samples with different quenching materials, 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 of the range of points where the average value is within 1 standard deviation of the 1 / e line. The results of the photoluminescence dynamics are shown in Figures 34, 35, and 37.

[0469] Diffusion modeling: 1D diffusion equation,

Equation

Number

Number

[0470] The following items are also disclosed together.

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

[0472] 2. The photovoltaic device according to item 1, wherein the thickness of the layer of perovskite semiconductor without open pores is from 100 nm to 100 μm.

[0473] 3. The thickness of the layer of the perovskite semiconductor without the open pores is from 100 nm to 700 nm, the photovoltaic device according to item 1 or 2.

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

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

[0476] 6. The thickness of the layer of the perovskite semiconductor without the open pores is from 100 nm to 100 μm, the photovoltaic device according to item 5.

[0477] 7. The thickness of the layer of the perovskite semiconductor without the open pores is from 100 nm to 700 nm, the photovoltaic device according to item 5.

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

[0479] 9. The porous material is a dielectric material, the photovoltaic device according to item 1 or 8.

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

[0481] 11. 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, the photovoltaic device according to any one of items 1 and 8 to 10.

[0482] 12. The 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 according to any one of items 1 and 8 to 12, wherein the thickness of the capping layer is thicker than the thickness of the first layer.

[0484] 14. The photovoltaic device according to 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. The photovoltaic device according to any one of items 1 to 14, wherein the n-type region includes 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 including 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 items 1 to 17, wherein the p-type region includes 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 including 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. The photovoltaic device according to any one of items 1 to 21, wherein the perovskite contains at least one anion selected from halide anions or chalcogenide anions.

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

[0494] 24. The second cation is 2+ Sn 2+ , Pb 2+ and Cu

[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 chemical formula (R1R2R3R4N) + and R1 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R2 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R3 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, and R4 is hydrogen, unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, The photovoltaic device according to item 25.

[0497] 27. The organic cation has the chemical formula (R5R6N=CH-NR7R8) + and R5 is hydrogen, unsubstituted or substituted C1-C 20is alkyl, or unsubstituted or substituted aryl, and R6 is hydrogen, unsubstituted or substituted C1-C 20 is alkyl, or unsubstituted or substituted aryl, and R7 is hydrogen, unsubstituted or substituted C1-C 20 is alkyl, or unsubstituted or substituted aryl, and R8 is hydrogen, unsubstituted or substituted C1-C 20 The photovoltaic device according to item 25, wherein is alkyl, or unsubstituted or substituted aryl.

[0498] 28. The photovoltaic device according to any one of items 22 to 27, wherein the perovskite is a mixed-anion perovskite containing 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. The 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. The 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. Comprising a first electrode, a second electrode, and the photoactive region disposed between the first electrode and the second electrode, wherein the second electrode is in contact with the n-type region of the photoactive region, the first electrode is in contact with 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, The photovoltaic device according to any one of items 1 to 31.

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

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

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

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

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

[0508] 38. A process for manufacturing a photovoltaic device comprising a photoactive region, wherein 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, Arranged between the n-type region and the p-type region, (1) A layer of a perovskite semiconductor without open pores, having a thickness of from 10 nm to 100 μm, forming a first planar heterojunction with the n-type region and a second planar heterojunction with the p-type region, a layer of a perovskite semiconductor without open pores, Or, (2) A first layer comprising a porous material and a perovskite semiconductor disposed within the pores of the porous material, A capping layer disposed on the first layer, wherein the capping layer is a layer of a perovskite semiconductor without open pores, the layer of a perovskite semiconductor without open pores has a thickness of from 10 nm to 100 μm, and the perovskite semiconductor of the capping layer contacts the perovskite semiconductor in the first layer, a capping layer, Comprising, the process comprising (a) Providing a first region, (b) Disposing a second region on the first region, the second region comprising the layer of a perovskite semiconductor without open pores, a step of disposing, (c) placing a third region on top of the second region; comprising wherein the first region is the n-type region including at least one n-type layer, and the third region is the p-type region including at least one p-type layer, or wherein 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, a process.

[0509] 39. The step (b) of placing the second region on top of the first region is a sub-step of forming a perovskite solid layer on top of the first region by vapor deposition, The process according to item 38, comprising.

[0510] 40. The step of forming a perovskite solid layer on top of the first region by vapor deposition is (i) a sub-step of exposing the first region to vapor, wherein the vapor contains the perovskite or one or more reactants for forming the perovskite; (ii) a sub-step of enabling deposition of the vapor onto the first region to form a perovskite solid layer on top of the first region, The process according to item 39, comprising.

[0511] 41. The process according to item 39 or 40, wherein the vapor deposition can continue until the perovskite solid layer has a thickness ranging from 100 nm to 100 μm.

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

[0513] 43. The step (b) of disposing the second region over the first region, which is a sub-step of forming the perovskite solid layer by vapor deposition, and the vapor deposition is dual-source vapor deposition, the forming sub-step, The process according to any one of items 38 to 42, including

[0514] 44. (i) A step of exposing the first region to vapor, wherein the vapor contains two reactants for forming the perovskite, the exposing step; (ii) A step of enabling the deposition of the vapor onto the first region to form a solid layer of the perovskite over the first region; including, (i) further includes a sub-step of generating the vapor containing two reactants for forming the perovskite by evaporating a first reactant from a first source and evaporating a second reactant from a second source, The process according to any one of items 38 to 43.

[0515] 45. The process according to item 44, wherein the first reactant includes a first compound containing (i) a metal cation and (ii) a first anion, and the second reactant includes a second compound containing (i) an organic cation and (ii) a second anion.

[0516] 46. The organic cation has the chemical formula (R1R2R3R4N) + and R1 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R2 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, R3 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, and R4 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, or unsubstituted or substituted aryl, 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 halide ions or chalcogenide ions.

[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 comprises a first compound that is BX2, and the second reactant comprises a second compound that 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+ and is a cation selected from X is an anion selected from F - , Cl - , Br - and I - and is an anion selected from A is a cation of the chemical formula (R5NH3) + , where R5 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, X’ is an anion selected from F - , Cl - , Br - and I - and is an anion selected from, and X and X’ are different anions, 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 is (iii) A sub-step of heating the solid layer of the perovskite, 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 is (i) A sub-step of exposing the first region to vapor, wherein the vapor contains a first perovskite precursor compound and enables deposition of the vapor on the first region to form a solid layer of the first perovskite precursor compound on the first region, (ii) A sub-step of treating the obtained solid layer of the first perovskite precursor compound with a solution containing a second perovskite precursor compound, thereby reacting the first perovskite precursor compound with the second perovskite precursor compound to form the layer of the perovskite semiconductor without open pores, including The first perovskite precursor compound contains (i) a first cation and (ii) a first anion, and the second perovskite precursor compound contains (i) a second cation and (ii) a second anion, 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 those defined in any one of items 45 to 48.

[0523] 53. The first perovskite precursor compound has the chemical formula BX2, and the second perovskite precursor compound has the chemical 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+ and is a cation selected from where X is F - , Cl - , Br - and I - and is an anion selected from where A is a cation of the chemical formula (R5NH3) + where R5 is hydrogen, or unsubstituted or substituted C1-C 20 alkyl, where X’ is F - , Cl - , Br - and I - and is an anion selected from, and X and X’ are the same or different anions, The process according to item 51.

[0524] 54. The step (b) of disposing the second region on the first region is (i) a sub-step of dispensing one or more precursor solutions on the first region, wherein the one or more precursor solutions contain the perovskite dissolved in a solvent, or one or more reactants for generating the perovskite dissolved in one or more solvents, the sub-step of dispensing, (ii) a sub-step of removing the one or more solvents to form a solid layer of the perovskite on the first region, The process according to item 38, comprising.

[0525] 55. Step (b) of disposing the second region on top of the first region, wherein (i) a sub-step of dispensing a precursor solution on top of the first region, wherein the precursor solution comprises the perovskite dissolved in a solvent; and (ii) a sub-step of removing the solvent to form a solid layer of the perovskite on top of the first region; The process according to item 38, comprising the above.

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

[0527] 57. The process according to any one of items 54 to 56, wherein the step of dispensing the one or more precursor solutions on top of the first region and the step of removing the one or more solvents are performed until the solid layer of the perovskite has a thickness ranging from 100 nm to 100 μm.

[0528] 58. Step (b) of disposing the second region on top of the first region, wherein (iii) a sub-step of heating the solid layer of the perovskite; The process according to any one of items 54 to 57, further comprising the above.

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

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

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

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

[0533] 63. The step (b) of disposing the second region on the first region is (i) a sub-step of disposing a porous material on the first region, and (ii) a sub-step of disposing the perovskite within the pores of the porous material to form the first layer, and a sub-step of further disposing the perovskite on top of the first layer to form the capping layer, The process according to item 62, comprising .

[0534] 64. The process according to item 63, wherein the step of disposing the perovskite within the pores of the porous material and the step of further disposing the perovskite on top of the first layer are carried out together in a single step.

[0535] 65. The step (i) of disposing the porous material on the first region is a sub-step of disposing a composition on the first region, the composition comprising the porous material and a solvent; and a sub-step of removing the solvent. The process according to item 63 or 64, comprising and .

[0536] 66. The step (i) of disposing the porous material on the first region comprises a sub-step of screen printing, doctor blading, spin coating, slot die coating or spray coating the composition on the first region. The process according to item 65.

[0537] 67. The step (i) of disposing the porous material on the first region further comprises a sub-step of heating the composition. The process according to item 65 or 66.

[0538] 68. The process according to item 65, wherein the composition does not contain a binder and the temperature at 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 the pores of the porous material to generate the first layer and further disposing the perovskite on top of the first layer to generate the capping layer is carried out until the capping layer has a thickness ranging from 100 nm to 100 μm.

[0540] 70. Step (ii) comprises: a sub-step of disposing one or more precursor solutions onto the porous material, wherein the one or more precursor solutions comprise the perovskite dissolved in a solvent, or one or more reactants for generating the perovskite dissolved in one or more solvents; a sub-step of removing the one or more solvents to generate a solid perovskite within the pores of the porous material and a solid capping layer of the perovskite disposed on top of the first layer; The process according to any one of items 65 to 69.

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

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

[0543] 73. Step (b) of disposing the second region over the first region comprises (iii) a sub-step of heating the perovskite, The process according to any one of items 65 to 72, further comprising.

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

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

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

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

[0548] 78. The process according to item 77, wherein the first electrode comprises a transparent material or a translucent material.

[0549] 79. A process for manufacturing a tandem junction or a multi-junction photovoltaic device, comprising (d) disposing a tunnel junction over the third region; (e) disposing a further photoactive region over the tunnel junction, the 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; further comprising the process according to any one of items 38 to 76.

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

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

Claims

1. A photovoltaic device that is a tandem-junction optoelectronic device or a multi-junction electronic device, wherein the photovoltaic device includes a photoactive region, and the photoactive region includes an n-type region including at least one n-type layer, and a p-type region including at least one p-type layer, and a layer of perovskite semiconductor without open pores is disposed between the n-type region and the p-type region. The photovoltaic device.

2. The photovoltaic device includes a first electrode and a second electrode, and between the first electrode and the second electrode, (i) the photoactive region, (ii) at least one other photoactive region are disposed. The photovoltaic device according to claim 1.

3. The thickness of the layer of the perovskite semiconductor without open pores is 10 nm to 100 μm. The photovoltaic device according to claim 1 or 2.

4. The thickness of the layer of the perovskite semiconductor without open pores is 100 nm to 100 μm. The photovoltaic device according to claim 1 or 2.

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

6. The layer of the perovskite semiconductor forms a first planar heterojunction with the n-type region and a second planar heterojunction with the p-type region. The photovoltaic device according to any one of claims 1 to 5.

7. The photoactive region includes the n-type region, and the p-type region, and between the n-type region and the p-type region, (i) a first layer including a porous scaffold material and a perovskite semiconductor disposed in the pores of the scaffold material, optionally, the scaffold material is a dielectric scaffold material or an electron transport scaffold material. The first layer, (ii) a capping layer disposed on the first layer, the capping layer is the layer of the perovskite semiconductor without open pores, and the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer. The capping layer are disposed. The photovoltaic device according to any one of claims 1 to 5.

8. The perovskite semiconductor includes at least one anion selected from halide anions. The photovoltaic device according to any one of claims 1 to 7.

9. The perovskite is a first cation that is an organic cation, a second cation that is a metal cation, and said at least one anion selected from halide anions, optionally further comprising a further cation or a further anion, the photovoltaic device according to claim 8.

10. The first cation is (H ２ N=CH-NH ２ ), and the second cation is Pb ＋ or Sn ２＋ or Sn ２＋ The photoelectric power generation element according to claim 9, wherein the photoelectric power generation element is such that

11. The photovoltaic device according to claim 2 or any one of claims 3 to 8 citing claim 2, wherein said at least one further photoactive region comprises at least one layer of a semiconductor material.

12. The photovoltaic device according to claim 11, wherein said semiconductor material comprises a layer of crystalline silicon, copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenosulfide, copper indium gallium selenide, copper indium gallium diselenide or copper indium selenide.

13. The photovoltaic device according to claim 11, wherein at least one layer of said semiconductor material comprises a layer of crystalline silicon.

14. The photovoltaic device according to claim 11, wherein said semiconductor material comprises a perovskite semiconductor.

15. The photovoltaic device according to claim 11, wherein said semiconductor material comprises an organic semiconductor.

16. The photovoltaic device according to claim 2 or any one of claims 3 to 8 citing claim 2, wherein said at least one further photoactive region comprises a heterojunction (c-Si HIT: Heterojunction with Intrinsic Thin layer) cell having an intrinsic thin layer.

17. A photovoltaic device according to any one of claims 1 to 11, wherein (A) the photovoltaic device has the following regions I. a first electrode, II. said photoactive region, III. a p-type semiconductor, optionally a layer (A) of p-type amorphous silicon, IV. an intrinsic semiconductor, optionally a first layer of intrinsic amorphous silicon, V. a layer (B) of a p-type semiconductor or a layer (B) of an n-type semiconductor, optionally a layer of p-type crystalline silicon or a layer of n-type crystalline silicon, VI. an intrinsic semiconductor, optionally a second layer of intrinsic amorphous silicon, VII. an n-type semiconductor, optionally a layer (C) of n-type amorphous silicon, VIII. a second electrode in this order, or (B) the photovoltaic device has the following regions I. a first electrode, II. said photoactive region, III. a layer of a transparent conductive oxide, IV. a layer (D) of an n-type semiconductor, wherein optionally said n-type semiconductor is a metal oxide or a metal chalcogenide, layer (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, and VI. A second electrode in this order, or (C) the photovoltaic device includes a first electrode and a second electrode, wherein between the first electrode and the second electrode, the photoactive region and at least one other photoactive region are arranged, each of the at least one other photoactive regions includes an n-type region including at least one n-type layer, and a p-type region including at least one p-type layer and includes, a layer of perovskite semiconductor without open pores is arranged between the n-type region and the p-type region. A photovoltaic device.

18. A process for manufacturing a photovoltaic device that is a tandem junction optoelectronic device or a multi-junction electronic device, wherein the photovoltaic device includes a photoactive region, and the photoactive region includes an n-type region including at least one n-type layer, and a p-type region including at least one p-type layer, a layer of perovskite semiconductor without open pores is arranged between the n-type region and the p-type region, the process includes (a) a step of providing a first region, (b) a step of arranging a second region on the first region, wherein the second region includes the layer of perovskite semiconductor without open pores, (c) a step of arranging a third region on the second region and includes, wherein the first region is the n-type region including at least one n-type layer, and the third region is the p-type region including at least one p-type layer, or 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. A process.

19. In the process according to claim 18, (d) a step of arranging a tunnel junction on the third region, (e) a step of arranging a further photoactive region on the tunnel junction, wherein the further photoactive region is the same as or different from the photoactive region defined in claim 18, (f) optionally a step of repeating steps (d) and (e), (g) a step of arranging an electrode on the further photoactive region arranged in the previous steps and further includes. A process.

20. The further photoactive region includes at least one layer of a semiconductor material, and at least one layer of the semiconductor material includes 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, a perovskite semiconductor, or an organic semiconductor, the process according to claim 19.

Images