Enhanced perovskite material for photovoltaic devices

Abstract

To improve perovskite material durability and efficiency.SOLUTION: A perovskite material has: a perovskite crystal lattice having the general formula of CxMyXz; and 1,4-diammonium butane cations disposed within or at a surface of the perovskite crystal lattice. In the formula, x, y and z are real numbers; C has one or more cations selected from the group consisting of Group 1 metals, Group 2 metals, ammonium, formamidinium, guanidinium, and ethene tetramine; M has one or more metals each selected from the group consisting of Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, Zr and combinations thereof; and X has one or more anions each selected from the group consisting of halides, sulfides, selenides, and combinations thereof.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 62 / 770,313, filed on November 21, 2018, entitled “Enhanced Perovskite Material for Photovoltaic Devices.” This application relates to an enhanced perovskite material for photovoltaic devices. [Background technology]

[0002] The use of photovoltaic (PV) power generation to produce electricity from solar energy or radiation can offer many advantages, including, for example, power supply, low or zero radiation, power generation independent of the power grid, durable physical structure (no moving parts), stable and reliable system, modular structure, relatively rapid deployment, safe manufacturing and use, and good public opinion and acceptance of use. [Overview of the Initiative] [Problems that the invention aims to solve]

[0003] PVs can incorporate a layer of perovskite material as a photoactive layer that generates electricity when exposed to light. Some photoactive layers can degrade due to environmental factors including temperature, humidity, and oxidation. Therefore, improvements in the durability and efficiency of perovskite materials are desired.

[0004] The features and advantages of this disclosure will be readily apparent to those skilled in the art. Many modifications can be made by those skilled in the art, but such modifications will remain within the scope of the spirit of the present invention. [Means for solving the problem]

[0005] To address the aforementioned problems with existing countermeasures, improved perovskite materials and methods for forming such materials are disclosed.

[0006] In one embodiment, the perovskite material is C x M y X zThe perovskite crystal lattice has the general formula , where x, y, and z are real numbers. Bulky organic cations are present on the surface or near grain boundaries of the perovskite crystal lattice. C contains one or more cations selected from the group consisting of Group 1 metals, Group 2 metals, ammonium, formamidinium, guanidinium, and ethenetetramine. M contains one or more metals selected from the group consisting of Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr, and combinations thereof. X contains one or more anions selected from the group consisting of halides, pseudohalides, chalcogenides (tellurides, oxides, sulfides, and selenides) and combinations thereof.

[0007] In certain embodiments, the tail group of at least one bulky organic cation is not chemically attached to the surface or grain boundary of the perovskite material.

[0008] In certain embodiments, bulky organic cations are present within the perovskite material crystal lattice at a distance of less than 50 nm from the surface or grain boundaries of the perovskite material crystal lattice.

[0009] In certain embodiments, the bulky organic cation is selected from the group consisting of n-butylammonium, benzylammonium, butane-1,4-diammonium, pentylammonium, hexylammonium, poly(vinylammonium), phenylethylammonium, 3-phenyl-1-propylammonium, 4-phenyl-1-butylammonium, 1,3-dimethylbutylammonium, 3,3-dimethylbutylammonium, and 1-octylammonium, as well as combinations thereof.

[0010] In certain embodiments, the bulky organic cation comprises 1-butylammonium.

[0011] In certain embodiments, the bulky organic cation comprises 1-hexylammonium.

[0012] In certain embodiments, the bulky organic cation comprises 1-octylammonium.

[0013] In certain embodiments, the bulky organic cation includes benzylammonium.

[0014] In certain embodiments, the crystal lattice of the perovskite material has a cubic structure.

[0015] In one embodiment, the perovskite material includes a lead-iodide-formamidinium perovskite material. Benzylammonium cations are present on the surface or near the grain boundaries of the formamidinium-iodide-formamidinium perovskite material.

[0016] In certain embodiments, at least one benzyl group of the benzylammonium cation is not chemically bonded to the grain boundaries or surfaces of the formamidinium lead iodide perovskite material.

[0017] In certain embodiments, the benzylammonium cation is located at a position of less than 50 nm within the formamidinium lead perovskite material, from the surface or grain boundaries of the formamidinium lead perovskite material.

[0018] In certain embodiments, the formamidinium lead iodide perovskite material has a cubic crystal structure.

[0019] In one embodiment, a method for forming a perovskite material includes the steps of: depositing a lead salt precursor on a substrate to form a lead salt thin film; depositing a bulky organic cation solution on the lead salt thin film; depositing a second salt precursor on the lead salt thin film to form a perovskite precursor thin film; and annealing the substrate to form a perovskite material.

[0020] In certain embodiments, the bulky organic cation solution comprises a bulky organic cation selected from the group consisting of n-butylammonium, benzylammonium, butane-1,4-diammonium, pentylammonium, hexylammonium, poly(vinylammonium), phenylethylammonium, 3-phenyl-1-propylammonium, 4-phenyl-1-butylammonium, 1,3-dimethylbutylammonium, 3,3-dimethylbutylammonium, 1-octylammonium, ammonium-functionalized perylene, and combinations thereof.

[0021] In certain embodiments, the bulky organic cation solution contains 1-butylammonium.

[0022] In certain embodiments, the bulky organic cation solution contains benzylammonium.

[0023] In certain embodiments, the bulky organic cation solution has a bulky organic cation concentration between 0.01 and 0.1 M.

[0024] In certain embodiments, the bulky organic cation solution has a bulky organic cation concentration between 0.03 and 0.05 M.

[0025] In certain embodiments, the lead salt precursor, the second salt precursor, and the bulky cation solution are deposited by spin coating, slot die printing, sputtering, PE-CVD, thermal deposition, or spray coating.

[0026] In certain embodiments, the lead salt precursor comprises one or more lead salts selected from the group consisting of lead(II) iodide, lead(II) thiocyanate, lead(II) chloride, lead(II) bromide, and combinations thereof.

[0027] In certain embodiments, the lead salt precursor includes lead(II) iodide.

[0028] In certain embodiments, the second salt precursor includes formamidinium iodide, formamidinium thiocyanate, or guanidinium thiocyanate.

[0029] In certain embodiments, the second salt precursor comprises formamidinium iodide.

[0030] In certain embodiments, the lead salt precursor comprises one or more solvents selected from the group consisting of N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof.

[0031] In certain embodiments, the lead salt precursor comprises one or more additives selected from the group consisting of amino acids, 5-aminovalerate hydroiodide, 1,8-diiodooctane, 1,8-dithiooctane, formamidinium halide, acetic acid, trifluoroacetic acid, methylammonium halide, water, and combinations thereof.

[0032] In certain embodiments, the lead salt precursor has PbI2:PbCl2 in a 90:10 molar ratio dissolved in anhydrous dimethylformamide.

[0033] In certain embodiments, annealing is performed in ambient air, a controlled humidity environment, or an atmosphere selected from the group consisting of pure argon, pure nitrogen, pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO2, and combinations thereof.

[0034] In certain embodiments, annealing is performed at a temperature between 50°C and 300°C.

[0035] In certain embodiments, annealing in a controlled humidity environment is 0 g H2O / m³3 Greater than air, 20 g H2O / m 3 It is carried out at an absolute humidity below air.

[0036] In certain embodiments, annealing in a controlled humidity environment occurs at an absolute humidity of about 4 - 7 g of H2O / m 3 of air.

[0037] In one embodiment, the perovskite material has a perovskite crystal lattice with the general formula C x M y X z where x, y, and z are real numbers. The 1,4-diammonium butane cation is disposed within or on the surface of the perovskite crystal lattice. C includes one or more cations selected from the group consisting of Group 1 metals, Group 2 metals, ammonium, formamidinium, guanidinium, and ethenetetramine. M includes one or more metals each selected from the group consisting of Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ga, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr, and combinations thereof. X includes one or more anions each selected from the group consisting of halides, pseudohalides, chalcogenides, and combinations thereof.

[0038] In certain embodiments, the 1,4-diammonium butane cation has a concentration between 1 mol% and 20 mol% in the perovskite material.

[0039] In certain embodiments, the 1,4-diammonium butane cation has a concentration of 1 mol% - 5 mol% in the perovskite material.

[0040] In certain embodiments, the 1,4-diammonium butane cation has a concentration of about 5 mol% in the perovskite material.

[0041] In certain embodiments, C includes formamidinium, M includes lead, and X includes iodide.

[0042] In certain embodiments, the crystal lattice of the perovskite material has a cubic structure.

[0043] In certain embodiments, the ammonium group of the 1,4-diammoniumbutane cation is substituted with a formamidinium ion within the perovskite crystal lattice.

[0044] In one embodiment, the perovskite material comprises a formamidinium lead iodide perovskite material and a 1,4-diammonium butane cation disposed inside or on the surface of the formamidinium lead iodide perovskite material.

[0045] In certain embodiments, the ammonium group of the 1,4-diammoniumbutane cation substitutes for the formamidinium ion within the perovskite crystal lattice.

[0046] In certain embodiments, the 1,4-diammonium butane cation is present in the perovskite material at concentrations between 1 mol% and 20 mol%.

[0047] In certain embodiments, the 1,4-diammonium butane cation is present in the perovskite material at a concentration of 1 mol% to 5 mol%.

[0048] In certain embodiments, the 1,4-diammonium butane cation is present in the perovskite material at a concentration of about 5 mol%.

[0049] In certain embodiments, the formamidinium lead iodide perovskite material has a cubic crystal structure.

[0050] In one embodiment, a method for depositing a perovskite material includes the step of depositing a lead salt precursor on a substrate to form a lead salt thin film. The lead salt precursor comprises a lead salt and a 1,4-diammonium butane salt. Next, a second salt precursor may be deposited on the lead salt thin film to form a perovskite precursor thin film. Then, the substrate and the perovskite precursor thin film may be annealed to form a perovskite material.

[0051] In certain embodiments, the lead salt precursor has a 1,4-diammonium butane concentration between 1 mol% and 20 mol%.

[0052] In certain embodiments, the lead salt precursor has a 1,4-diammonium butane concentration between 1 mol% and 5 mol%.

[0053] In certain embodiments, the lead salt precursor has a 1,4-diammonium butane concentration of about 5 mol%.

[0054] In certain embodiments, the lead salt precursor comprises one or more lead salts selected from the group consisting of lead(II) iodide, lead(II) thiocyanate, lead(II) chloride, lead(II) bromide, and combinations thereof.

[0055] In certain embodiments, the lead salt precursor includes lead(II) iodide.

[0056] In certain embodiments, the second salt precursor includes a salt selected from the group consisting of formamidinium iodide, formamidinium thiocyanate, guanidinium thiocyanate, and combinations thereof.

[0057] In certain embodiments, the second salt precursor comprises formamidinium iodide.

[0058] In certain embodiments, the lead salt precursor comprises one or more solvents selected from the group consisting of N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethyl sulfoxide, methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof.

[0059] In certain embodiments, the lead salt precursor comprises one or more additives selected from the group consisting of amino acids, 5-aminovalerate hydroiodide, 1,8-diiodooctane, 1,8-dithiooctane, formamidinium halide, acetic acid, trifluoroacetic acid, methylammonium halide, water, and combinations thereof.

[0060] In certain embodiments, the lead salt precursor has PbI2:PbCl2 in a 90:10 molar ratio dissolved in anhydrous dimethylformamide.

[0061] In certain embodiments, annealing is performed in ambient air, a controlled humidity environment, or an atmosphere selected from the group consisting of pure argon, pure nitrogen, pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO2, and combinations thereof.

[0062] In certain embodiments, annealing is performed at a temperature between 50°C and 300°C.

[0063] In certain embodiments, annealing in a controlled humidity environment is 0 g H2O / m³ 3 Higher than air, 20g H2O / m³ 3 It is carried out at an absolute humidity below that of air.

[0064] In certain embodiments, annealing in a controlled humidity environment is performed with approximately 4-7 g of H2O / m³. 3 This is done using the absolute humidity of the air.

[0065] In one embodiment, a method for depositing a perovskite material includes the step of depositing a lead salt precursor on a substrate to form a lead salt thin film. Next, a 1,4-diammonium butane salt precursor is deposited on the lead salt thin film. Then, a third salt precursor may be deposited on the lead salt thin film to form a perovskite precursor thin film. Next, the substrate and the perovskite precursor thin film may be annealed to form a perovskite material.

[0066] In certain embodiments, the lead salt precursor has a 1,4-diammonium butane concentration between 1 mol% and 5 mol%.

[0067] In certain embodiments, the lead salt precursor comprises lead(II) iodide, and the third salt precursor comprises formamidinium iodide.

[0068] In certain embodiments, the lead salt precursor has a 90:10 molar ratio of PbI2:PbCl2 dissolved in anhydrous dimethylformamide and contains 10 mol% cesium. Annealing is carried out at a temperature between 50°C and 300°C. [Brief explanation of the drawing]

[0069] [Figure 1] This is a schematic diagram of a typical photovoltaic cell including an active layer according to one embodiment of the present disclosure. [Figure 2] This is a stylized diagram showing components of an example PV device according to one embodiment of the present disclosure. [Figure 3] This is a stylized diagram showing components of an example apparatus according to one embodiment of the present disclosure. [Figure 4] This is a stylized diagram showing components of an example apparatus according to one embodiment of the present disclosure. [Figure 5] This is a stylized diagram showing the Ruddlesden-Popper perovskite. [Figure 6] This is a stylized diagram showing a perovskite material with the addition of alkylammonium cations according to one embodiment of the present disclosure. [Figure 7] This is a stylized diagram showing a perovskite material having a 1-butylammonium surface layer according to one embodiment of the present disclosure. [Figure 8] This is a stylized diagram showing a perovskite material having multiple bulky organic cation surface layers according to one embodiment of the present disclosure. [Figure 8A] This is a stylized diagram showing a perovskite material having multiple bulky organic cation surface layers according to one embodiment of the present disclosure. [Figure 9] This figure shows a comparison of images of a perovskite material with and without a 1-butylammonium ("BAI") surface coating according to one embodiment of the present disclosure. [Figure 10] This is a stylized figure showing a comparison of images taken of a perovskite material with and without a 1-butylammonium ("BAI") surface coating, according to one embodiment of the present disclosure. [Figure 11A] This figure shows various perylene monoimides and diimides that may be applied to the surface of a perovskite material according to one embodiment of the present disclosure. [Figure 11B] This figure shows various perylene monoimides and diimides that may be applied to the surface of a perovskite material according to one embodiment of the present disclosure. [Figure 11C] This figure shows various perylene monoimides and diimides that may be applied to the surface of a perovskite material according to one embodiment of the present disclosure. [Figure 11D] This figure shows various perylene monoimides and diimides that may be applied to the surface of a perovskite material according to one embodiment of the present disclosure. [Figure 12] This is a stylized diagram showing a perovskite material with the addition of perylene monoimideammonium cations according to one embodiment of the present disclosure. [Figure 13]This is a stylized diagram showing 1,4-diammonium butane incorporated into the crystal lattice of a lead iodide perovskite formamidenium material according to one embodiment of the present disclosure. [Figure 14] This figure shows the X-ray diffraction peaks (XRD) of perovskites having 1,4-diammonium butane at various concentrations according to one embodiment of the present disclosure. [Figure 15] These are images over time of perovskite material samples having 1,4-diammonium butane at various concentrations, according to one embodiment of the present disclosure. [Figure 16] This figure shows a polyammonium alkyl cation according to one embodiment of the present disclosure. [Figure 16A] This is a stylized diagram showing a figure of 1,8-diammonium octane incorporated into the crystal lattice of a formamidinium lead iodide perovskite material according to one embodiment of the present disclosure. [Figure 16B] This is a stylized diagram showing a figure of bis(4-aminobutyl)-ammonium incorporated into the crystal lattice of a lead iodide perovskite formamidenium material according to one embodiment of the present disclosure. [Figure 16C] This is a stylized figure showing tris(4-aminobutyl)-ammonium incorporated into the crystal lattice of a formamidinium lead iodide perovskite material according to one embodiment of the present disclosure. [Figure 17] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 18] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 19] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 20] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 21] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 22] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 23] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 24] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 25] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 26] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 27] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 28] This figure shows the structure of a specific organic molecule according to one embodiment of the present disclosure. [Figure 29] This figure shows the X-ray diffraction pattern of a perovskite material according to one embodiment of the present disclosure. [Figure 30] This is a stylized diagram of the thickness of an inorganic metal halide sublattice in a perovskite material according to one embodiment of the present disclosure. [Figure 31] This figure shows optical and photoluminescent images of a perovskite material photovoltaic device according to one embodiment of the present disclosure. [Figure 32] This figure shows the power output curve of a perovskite material photovoltaic device according to one embodiment of the present disclosure. [Figure 33] This figure shows the current-voltage (IV) scanning of a perovskite material photovoltaic device according to one embodiment of the present disclosure. [Figure 34] This figure shows a box plot of the open-circuit voltage (Voc), short-circuit current density (Jsc), filling efficiency (FF), and power conversion efficiency (PCE) of a perovskite material photovoltaic device according to one embodiment of the present disclosure. [Figure 35] This figure shows the external quantum efficiency (EQE) curve of a perovskite material photovoltaic device according to one embodiment of the present disclosure. [Figure 36] This figure shows an admitance spectroscopy plot of a perovskite material photovoltaic device according to one embodiment of the present disclosure. [Modes for carrying out the invention]

[0070] Improvements in various aspects of PV technology compatible with organic PV, inorganic PV, and / or hybrid PV are expected to further reduce the costs of both organic PV and other PV technologies. For example, in some solar cells, such as perovskite solar cells, it becomes possible to utilize new, cost-effective, and highly stable alternative materials, such as nickel oxide interface layers. Furthermore, various solar cells advantageously contain chemical additives and other materials, which are, among other things, more cost-effective and durable than existing conventional options.

[0071] This disclosure generally relates to apparatuses, methods, and compositions of materials that use materials in a photovoltaic cell to generate electrical energy from solar radiation. More specifically, this disclosure relates to compositions of photoactive materials and other materials, as well as apparatuses, methods of use, and formation of such compositions of materials.

[0072] Some or all of the materials according to certain embodiments of this disclosure can be significantly used in any organic or other electronic device, some examples of which include, but are not limited to, batteries, field-effect transistors (FETs), light-emitting diodes (LEDs), nonlinear optical devices, memristors, capacitors, rectifiers, and / or rectifier antennas.

[0073] In some embodiments, this disclosure provides PVs and other similar devices (e.g., batteries, hybrid PV batteries, multi-junction PVs, FETs, LEDs, X-ray detectors, gamma-ray detectors, photodiodes, CCDs, etc.). In some embodiments, such devices may include improved active materials, an interfacial layer (IFL), and / or one or more perovskite materials. The perovskite materials may be incorporated in one or more different embodiments of the PV or other devices. A perovskite material according to one embodiment may have the general formula CMX3, where C has one or more cations (e.g., amines, ammonium, phosphonium, Group 1 metals, Group 2 metals, and / or other cations or cation-like compounds), M has one or more metals (e.g., Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr), and X has one or more anions. Perovskite materials according to various embodiments will be discussed in more detail below.

[0074] Photovoltaic cells and other electronic devices A certain PV embodiment can be described with reference to an exemplary diagram of a solar cell, such as that shown in Figure 1. An exemplary PV architecture according to a certain embodiment may substantially take the form of substrate-anode-IFL-active layer-IFL-cathode. The active layer in a certain embodiment may be photoactive and / or may contain a photoactive material. Other layers and materials may be utilized in the cell, as is conventionally known. Furthermore, it should be noted that the use of the term “active layer” does not mean to restrict or otherwise define, explicitly or implicitly, the properties of any other layer. For example, in a certain embodiment, either or both of the IFLs may be active if they are semiconductors. Referring particularly to Figure 1, a stylized general PV cell 1000 is shown, which demonstrates the high interfacial properties of several layers within the PV. PV 1000 represents a general architecture applicable to several PV devices, such as perovskite material PV embodiments. PV cell 1000 has a transparent substrate layer 1010, which may be glass (or a material equally transparent to solar radiation), so that solar radiation can pass through the layer. In some embodiments, the transparent layer may also be referred to as a superstraight or substrate (for example, as substrate layer 3901 in Figure 2) and may have one or more of various rigid or flexible materials such as glass, polyethylene, polypropylene, polycarbonate, polyimide, PMMA, PET, PEN, Kapton, or quartz. Generally, the term substrate is used to refer to the material on which the device is deposited during manufacturing. The photoactive layer 1040 may consist of an electron donor or p-type material, and / or an electron acceptor or n-type material, and / or a bipolar semiconductor exhibiting both p-type and n-type material properties, and / or an intrinsic semiconductor exhibiting neither n-type nor p-type properties. In some embodiments, the photoactive layer 1040 may be a perovskite material as described herein. As shown in Figure 1, the active layer or photoactive layer 1040 is sandwiched between two conductive electrode layers 1020 and 1060. In Figure 1, the electrode layer 1020 may be a transparent conductor such as tin-doped indium oxide (ITO material) or other materials described in this application.In other embodiments, the second substrate 1070 and the second electrode 1060 may be transparent. As previously stated, the active layer in some embodiments does not necessarily have to be photoactive. However, in the device shown in Figure 1, it is photoactive. The electrode layer 1060 may be aluminum or other metals, or other conductive materials such as carbon. Other conventionally known materials may be used. The cell 1010 also has an interface layer (IFL) 1030 as shown in the example in Figure 1. The IFL can assist in charge separation. In other embodiments, the IFL 1030 may have a multilayer IFL, which will be discussed in detail later. There may also be an IFL 1050 adjacent to the electrode 1060. In some embodiments, the IFL 1050 adjacent to the electrode 1060 may have a further multilayer IFL, or instead have a multilayer IFL (again, described in detail later). The IFL in some embodiments may be semiconductor in nature, and may be intrinsic, bipolar, p-type, or n-type, or may be dielectric in nature. In one embodiment, the cathode-side IFL of the device (e.g., IFL1050 as shown in Figure 1) may be p-type, and the anode-side IFL of the device (e.g., IFL1030 as shown in Figure 1) may be n-type. However, in other embodiments, the cathode-side IFL may be n-type and the anode-side IFL may be p-type. Cell 1010 may be attached to electrical leads by electrodes 1060 and 1020, as well as by discharge units such as batteries, motors, capacitors, power grids, or other electrical loads.

[0075] Various embodiments of this disclosure provide improved materials and / or designs for various embodiments of solar cells and other devices, including active materials (including hole transport layers and / or electron transport layers), interface layers, and overall device designs.

[0076] interfacial layer In one embodiment, the disclosure provides advantageous materials and designs for one or more interface layers in a PV, including a thin-film coated IFL. The thin-film coated IFL may be used in one or more IFLs of a PV according to the various embodiments discussed herein.

[0077] In various embodiments, the device may have an interfacial layer between any two other layers and / or materials, if necessary. However, the device is not required to include any interfacial layers. For example, a perovskite material device may have 0, 1, 2, 3, 4, 5, or more interfacial layers (for example, the device in the example in Figure 2 has five interfacial layers 3903, 3905, 3907, 3909, and 3911). The interfacial layer may have any suitable material to enhance the transport and / or collection of charges between the two layers or materials. This also helps to avoid or reduce the possibility of charge recombination once charges have been transported away from one of the materials adjacent to the interfacial layer. The interfacial layer may further physically and electrically homogenize its substrate, resulting in variations in substrate roughness, dielectric constant, adhesion, defect occurrence, or disappearance (e.g., charge trapping, surface state).A suitable interface material may have any one or more of the following: Ag, Al, Au, B, Bi, Ca, Cd, Ce, Co, Cu, Cu, Fe, Ga, Ge, H, In, Mg, Mn, Mo, Nb, Nt, Sb, Sc, Sn, Ta, Ti, V, W, Y, Zn, Zr; any carbide of the above metals (e.g., SiC, Fe3C, WC, VC, MoC, NbC); any silicide of the above metals (e.g., Mg2Si, SrSi2, Sn2Si); any oxide of the above metals (e.g., (e.g., alumina, silica, titania, SnO2, ZnO, NiO, ZrO2, HfO2) and containing transparent conductive oxides ("TCO") such as indium tin oxide, aluminum-doped zinc oxide (AZO), cadmium oxide (CdO), and fluorine-doped tin oxide (FTO); any sulfide of the above metals (e.g., CdS, MoS2, SnS2); any nitride of the above metals (e.g., GaN, Mg3N2, TiN, BN, Si3N4); any of the above metals Selenides of the above metal (e.g., CdSe, FeS2, ZnSe); any tellurides of the above metal (e.g., CdTe, TiTe2, ZnTe); any phosphides of the above metal (e.g., InP, GaP, GaInP); any arsenides of the above metal (e.g., CoAs3, GaAs, InGaAs, NiAs); any antimonides of the above metal (e.g., AlSb, GaSb, InSb); any halides of the above metal (e.g., CuCl, CuI, BiI3); the above metal Any pseudohalides of the genus (e.g., CuSCN, AuCN, Fe(SCN)2); any carbonates of the above metals (e.g., CaCO3, Ce2(CO3)3); functionalized or unfunctionalized alkylsilyl groups; graphite; graphene; fullerene; carbon nanotubes; any mesoporous and / or interfacial materials discussed elsewhere in this application; and combinations thereof (in some embodiments, including bilayers, trilayers, or multilayers of the combination materials). In some embodiments, the interfacial layer may have a perovskite material. Furthermore, the interfacial layer may include doped embodiments of any interfacial material described herein (e.g., Y-doped ZnO, N-doped single-phase wall carbon nanotubes).The interfacial layer may also have a compound containing three of the aforementioned materials (e.g., CuTiO3, Zn2SnO4), or a compound containing four of the aforementioned materials (e.g., CoNiZnO). The materials listed above may exist in planar, mesoporous, or other nanostructure forms (e.g., rods, spheres, flowers, pyramids), or as aerogel structures.

[0078] Firstly, as described above, one or more IFLs (e.g., either or both of IFLs 2626 and 2627 as shown in Figure 1) may contain the photoactive organic compound of the Disclosure as a self-assembled monolayer (SAM) or as a thin film. When the photoactive organic compound of the Disclosure is applied as a SAM, it may have a bonding group through which it is covalently or otherwise bonded to either or both of the anode and cathode surfaces. The bonding group in one embodiment may have any one or more of COOH, SiX3 (wherein X may be any part suitable for forming a ternary silicon compound such as Si(OR)3 and SiCl3), SO3, PO4H, OH, CH2X (wherein X may have a halogenated group 17), and O. The bonding group may be covalently or otherwise bonded to the electron extraction portion, electron donating portion, and / or core portion. The binding group may be attached to the electrode surface such that a single (or, in some embodiments, multiple) oriented organic layer is formed in thickness (e.g., when multiple photoactive organic compounds are bonded to the anode and / or cathode). As previously stated, the SAM may be attached via covalent interactions, but in some embodiments, it may be attached via ionic, hydrogen bonding, and / or dispersion force (i.e., van der Waals) interactions. Furthermore, in certain embodiments, upon exposure, the SAM enters a zwitterionic excited state, thereby forming a highly polarized IFL that can guide charge carriers from the active layer to the electrode (e.g., anode or cathode). In some embodiments, this enhanced charge carrier implantation can be achieved by electronically polishing the cross-section of the active layer and further increasing the drift rate of charge carriers toward each electrode (e.g., holes to the anode, electrons to the cathode). A molecule for anode application in some embodiments has a tunable compound which includes a primary electron donor moiety bonded to a core portion, this core portion bonded to an electron extraction portion, which may be bonded to a binding group.In a cathode application according to one embodiment, the IFL molecule has a tunable compound having an electron-deficient moiety bonded to a core portion, which is bonded to an electron-donor moiety, which may be bonded to a binding group. When a photoactive organic compound is used as an IFL according to such an embodiment, it may maintain its photoactive properties. However, in some embodiments, it is not necessary for it to be photoactive.

[0079] The metal oxide used in the thin-film IFL in some embodiments may be a semiconductor metal oxide such as NiO, SnO2, WO3, V2O5, or MoO3. Embodiments in which the second (e.g., n-type) active material is TiO2 coated with a thin-film coated IFL containing Al2O3 can be formed with a precursor material such as Al(NO3)3·xH2O, or any other material suitable for depositing Al2O3 on TiO2, after which thermal annealing and die coating are performed. In exemplary embodiments in which a MoO3 coating is used instead, the coating may be formed with a precursor material such as Na2Mo4·2H2O. On the other hand, V2O5 coatings in some embodiments may be formed with a precursor material such as NaVO3. WO3 coatings in some embodiments may be formed with a precursor material such as NaWO4·H2O. The concentration of the precursor material (e.g., Al(NO3)3·xH2O) may affect the thickness of the final film (here, Al2O3) deposited on TiO2 or the other active material. Therefore, changing the concentration of the precursor material can be a way to control the final film thickness. For example, a larger film thickness may result from a larger precursor material concentration. A larger film thickness does not necessarily result in a larger PCE in PV devices having a metal oxide coating. Therefore, the method of one embodiment may include the step of coating a TiO2 (or other mesoporous) layer with a precursor material having a concentration in the range of about 0.5 to 10.0 mM. Another embodiment may include the step of coating the layer with a precursor material having a concentration in the range of about 2.0 to 6.0 mM. Or, in another embodiment, the concentration may be about 2.5 to 5.5 mM.

[0080] Furthermore, although this application refers to it as Al2O3 and / or alumina, it should be noted that various proportions of aluminum and oxygen may be used to form alumina. Therefore, in some embodiments discussed in this application, although it is written as Al2O3, such a description is not intended to specify a required ratio of aluminum to oxygen. Rather, the embodiments include any one or more aluminum oxide compounds, each of which is Al x O y It has an aluminum oxide ratio represented by , where x may be any value between about 1 and 100, an integer or a non-integer. In some embodiments, x may be between about 1 and 3 (again, it does not have to be an integer). Similarly, y may be any value between 0.1 and 100, an integer or a non-integer. In some embodiments, y may be between 2 and 4 (again, it does not have to be an integer). Furthermore, in various embodiments, Al may be in alpha, gamma, and / or amorphous forms of alumina. x O y Various crystalline forms may exist.

[0081] Similarly, although these compounds are referred to in this application as NiO, MoO3, WO3, and V2O5, instead, Ni x O y Mo x O y , W x O y , and V x O y It may also be expressed as: Mo x O y and W x O y For each of these, x may be any value between approximately 0.5 and 100, an integer or a non-integer. In some embodiments, it may be between approximately 0.5 and 1.5. Similarly, y may be any value between approximately 1 and 100, an integer or a non-integer. In some embodiments, y may be any value between approximately 1 and 4. x O yWith respect to x, x may be any value between approximately 0.5 and 100, an integer or a non-integer, and in some embodiments, it may be between approximately 0.5 and 1.5. Similarly, y may be any value between approximately 1 and 100, an integer or a non-integer. In certain embodiments, it may be an integer or a non-integer value between approximately 1 and 10. In some embodiments, x and y may have values ​​that result in a non-stoichiometric ratio.

[0082] In some embodiments, IFL may comprise a titanate. In some embodiments, the titanate is represented by the general formula M'TiO3, where M' comprises any 2+ cation. In some embodiments, M' may be a cationic form of Be, Mg, Ca, Sr, Ba, Ni, Zn, Cd, Hg, Cu, Pd, Pt, Sn, or Pb. In some embodiments, IFL may comprise a single species of titanate, while in other embodiments, IFL may comprise two or more different species of titanate. In some embodiments, the titanate has the general formula SrTiO3. In other embodiments, the titanate may have the formula BaTiO3. In yet another embodiment, the titanate may have the general formula CaTiO3.

[0083] For illustrative purposes only and without any intention of limitation, titanates possess a perovskite crystal structure and strongly seed the growth transformation process of perovskite materials (e.g., methylammonium lead iodide (MAPbI3) and formamidinium lead iodide (FAPbI3)). In general, titanates also satisfy other IFL requirements such as ferroelectric behavior, sufficient charge carrier mobility, light transmittance, matched energy levels, and high dielectric constant.

[0084] In other embodiments, IFL may contain a zirconate. In some embodiments, the zirconate may be represented by the general formula M'ZrO3, where M' has any 2+ cation. In some embodiments, M' may have the cationic form of Be, Mg, Ca, Sr, Ba, Ni, Zn, Cd, Hg, Cu, Pd, Pt, Sn, or Pb. In some embodiments, IFL has a single chemical species of zirconate, and in other embodiments, IFL may have two or more different chemical species of zirconate. In some embodiments, the zirconate has the general formula SrZrO3. In another embodiment, the zirconate may have the general formula BaZrO3. In yet another embodiment, the zirconate may have the general formula CaZrO3.

[0085] For illustrative purposes only and without any limitation, zirconates possess a perovskite crystal structure and strongly seed the growth and transformation process of perovskite materials (e.g., MAPbI3, FAPbI3). In general, zirconates also satisfy other IFL requirements such as ferroelectric behavior, sufficient charge carrier mobility, light transmittance, matched energy levels, and high dielectric constant.

[0086] In another embodiment, IFL may have a stanate. In one embodiment, the stanate may be represented by the general formula M'SnO3 or M'2SnO4, where M' has any 2+ cation. In one embodiment, M' may have the cationic form of Be, Mg, Ca, Sr, Ba, Ni, Zn, Cd, Hg, Cu, Pd, Pt, Sn, or Pb. In one embodiment, IFL has a single chemical species of stanate, and in another embodiment, IFL may have two or more different chemical species of stanate. In one embodiment, the stanate has the general formula SrSnO3. In another embodiment, the stanate may have the general formula BaSnO3. In yet another embodiment, the stanate may have the general formula CaSnO3.

[0087] For illustrative purposes only and without any limitation, stannates possess a perovskite crystal structure and strongly seed the growth and transformation process of perovskite materials (e.g., MAPbI3, FAPbI3). In general, stannates also satisfy other IFL requirements such as ferroelectric behavior, sufficient charge carrier mobility, light transmittance, matched energy levels, and high dielectric constant.

[0088] In another embodiment, IFL may have a lead salt. In one embodiment, the lead salt may have the general formula M'PbO3, where M' contains any 2+ cation. In one embodiment, M' may have the cationic form of Be, Mg, Ca, Sr, Ba, Ni, Zn, Cd, Hg, Cu, Pd, Pt, Sn, or Pb. In one embodiment, IFL has a lead salt of a single chemical species, and in another embodiment, IFL may have two or more different types of lead salts. In one embodiment, the lead salt has the general formula SrPbO3. In another embodiment, the lead salt may have the general formula BaPbO3. In yet another embodiment, the lead salt may have the general formula CaPbO3. In yet another embodiment, the lead salt has the general formula Pb II Pb IV It may contain O3.

[0089] For illustrative purposes only and without any limitation, lead salts possess a perovskite crystal structure and strongly seed the growth transformation process of perovskite materials (e.g., MAPbI3, FAPbI3). In general, lead salts also satisfy other IFL requirements such as ferroelectric behavior, sufficient charge carrier mobility, light transmittance, matched energy levels, and high dielectric constant.

[0090] Furthermore, in another embodiment, IFL is given by the general formula M'[Zr x Ti 1-xIFL has a combination of zirconate and titanate in ]O3, where X is greater than 0 but less than 1, and M' contains any 2+ cation. In some embodiments, M' may have a cationic form of Be, Mg, Ca, Sr, Ba, Ni, Zn, Cd, Hg, Cu, Pd, Pt, Sn, or Pb. In some embodiments, IFL has a single chemical species of zirconate, and in other embodiments, IFL may have two or more different chemical species of zirconate. In one embodiment, the zirconate / titanate combination has the general formula Pb[Zr x Ti 1-x It has ]O3. In another embodiment, the zirconate / tiantate combination has the general formula Pb[Zr 0.52 Ti 0.48 It contains ]O3.

[0091] For illustrative purposes only and without any intention of limitation, zirconate / titanate combinations possess a perovskite crystal structure and strongly seed the growth transformation process of perovskite materials (e.g., MAPbI3, FAPbI3). In general, zirconate / titanate combinations also satisfy other IFL requirements such as ferroelectric behavior, sufficient charge carrier mobility, light transmittance, matched energy levels, and high dielectric constant.

[0092] In other embodiments, IFL may have a niobate salt. In some embodiments, the niobate salt may be represented by the general formula M'NbO3, where M' has any 1+ cation. In some embodiments, M' may have a cationic form of Li, Na, K, Rb, Cs, Cu, Ag, Au, Tl, ammonium, or H. In some embodiments, IFL has a single chemical species of niobate salt, and in other embodiments, IFL may have two or more different chemical species of niobate salt. In some embodiments, the niobate salt has the general formula LiNbO3. In other embodiments, the niobate salt may have the general formula NaNbO3. In yet another embodiment, the niobate salt may have the general formula AgNbO3.

[0093] For illustrative purposes only and without any limitation, niobates generally satisfy IFL requirements such as piezoelectric behavior, nonlinear optical polarity, photoelasticity, ferroelectricity, Pockels effect, sufficient charge carrier mobility, light transmittance, matched energy levels, and high dielectric constant.

[0094] In one embodiment, the perovskite material device is formed by casting PbI2 onto a SrTiO3-coated ITO substrate. The PbI2 may be converted to MAPbI3 by an immersion process, which will be described in more detail later. This conversion of PbI2 to MAPbI3 is more complete (as observed by optical spectroscopy) compared to the preparation of a substrate that does not contain SrTiO3.

[0095] The interface materials described herein may further have a doped composition. To modify the properties of the interface material (e.g., electrical, optical, mechanical), stoichiometric or non-stoichiometric materials may be doped with one or more elements (e.g., Na, Y, Mg, N, P) in amounts ranging from 1 ppb% to 50 mol%. Some examples of interface materials include NiO, TiO2, SrTiO3, Al2O3, ZrO2, WO3, V2O5, MO3, ZnO, graphene, and carbon black. Examples of possible dopants for these interface materials include Li, Na, Be, Mg, Ca, Sr, Ba, Sc, Y, Nb, Ti, Fe, Co, Ni, Cu, Ga, Sn, In, B, N, P, C, S, As, halides, pseudohalides (e.g., cyanides, cyanates, isocyanates, fulminates, thiocyanates, isothiocyanates, azides, tetracarbonylcobaltates, carbamoyldicyanonemethanides, dicyanonitrosometanides, dicyanamides and tricyanomethanides), and Al in any oxidation state. Herein, references to doped interface materials are not intended to limit the ratio of components in the interface material compounds.

[0096] In one embodiment, multiple IFLs made from different materials may be arranged adjacent to each other to form a composite IFL. This configuration may include two different IFLs, three different IFLs, or even more different IFLs. The resulting multilayer or composite IFL can be used in place of a single-material IFL. For example, the composite IFL may use any of the IFLs shown in the example in Figure 2, such as IFL3903, IFL3905, IFL3907, IFL3909, or IFL3911. Although the composite IFL is different from the single-material IFL, an assembly of perovskite material PV cells having multilayer IFLs is substantially no different from an assembly of perovskite material PV cells having only single-material IFLs.

[0097] In general, composite IFLs can be fabricated using any material suitable for the IFLs shown in this application. In some embodiments, the IFL has a layer of Al2O3 and a layer of ZnO or M:ZnO (doped ZnO, e.g., Be:ZnO, Mg:ZnO, Ca:ZnO, Sr:ZnO, Ba:ZnO, Sc:ZnO, Y:ZnO, Nb:ZnO). In some embodiments, the IFL has a layer of ZrO2 and a layer of ZnO or M:ZnO. In certain embodiments, the IFL has multiple layers. In some embodiments, a multilayer IFL generally has a conductive layer, a dielectric layer and a semiconductor layer. In certain embodiments, the layers may be repeated, for example, a conductive layer, a dielectric layer, a semiconductor layer, a dielectric layer, and a semiconductor layer. Examples of multilayer IFLs include IFLs having an ITO layer, an Al2O3 layer, a ZnO layer, and a second Al2O3 layer; IFLs having an ITO layer, an Al2O3 layer, a ZnO layer, a second Al2O3 layer, and a second ZnO layer; IFLs having an ITO layer, an Al2O3 layer, a ZnO layer, a second Al2O3 layer, a second ZnO layer, and a third Al2O3 layer; and IFLs having any number of layers necessary to achieve the desired performance characteristics. As stated above, references to specific stoichiometric ratios are not intended to limit the proportions of constituent components in the IFL layers according to the various embodiments.

[0098] When two or more adjacent IFLs are arranged as a composite IFL, it may outperform a single IFL in a perovskite PV cell, and the contributions from each IFL material can be utilized in a single IFL. For example, in an architecture having an ITO layer, an Al2O3 layer, and a ZnO layer, ITO is a conductive electrode, Al2O3 is a dielectric material, and ZnO is an n-type semiconductor, acting as an electron acceptor with good electron transport properties (e.g., mobility). Furthermore, Al2O3 is a physically robust material, adheres well to ITO, homogenizes the surface by capping surface defects (e.g., charge traps), and improves the characteristics of the device diode by suppressing dark current.

[0099] Furthermore, a certain perovskite material PV cell may have a so-called "tandem" PV cell having two or more perovskite photoactive layers. For example, both photoactive materials 3908 and 3906 in Figure 2 may be perovskite materials. In such a tandem PV cell, the interface layer between the two photoactive layers, such as IFL3907 in Figure 2, may have a multilayer or composite IFL. In one embodiment, the layer sandwiched between the two photoactive layers of the tandem PV device may include an electrode layer.

[0100] The tandem PV device may include the following layers in top-to-bottom or bottom-to-top order: a first substrate, a first electrode, a first interface layer, a first perovskite material, a second interface layer, a second electrode, a third interface layer, a second perovskite material, a fourth interface layer, and a third electrode. In one embodiment, the first and third interface layers may be hole transport interface layers, and the second and fourth interface layers may be electron transport interface layers. In another embodiment, the first and third interface layers may be electron transport interface layers, and the second and fourth interface layers may be hole transport interface layers. In yet another embodiment, the first and fourth interface layers may be hole transport interface layers, and the second and third interface layers may be electron transport interface layers. In yet another embodiment, the first and fourth interface layers may be electron transport interface layers, and the second and third interface layers may be hole transport interface layers. In a tandem PV device, the first and second perovskite materials may have different band gaps. In one embodiment, the first perovskite material may be lead formamidinium bromide (FAPbBr3) and the second perovskite material may be lead formamidinium iodide (FAPbI3). In another embodiment, the first perovskite material may be lead methylammonium bromide (MAPbBr3) and the second perovskite material may be lead formamidinium iodide (FaPbI3). In yet another embodiment, the first perovskite material may be lead methylammonium bromide (MAPbBr3) and the second perovskite material may be lead methylammonium iodide (MAPbI3).

[0101] Perovskite materials The perovskite material may be incorporated into one or more embodiments of the PV or other devices. The perovskite material according to one embodiment is of the general formula C w M y X zIt may also be represented as CMX3, where C comprises one or more cations (e.g., amines, ammonium, phosphonium, Group 1 metals, Group 2 metals, and / or other cations or cationic compounds), M comprises one or more metals (e.g., having Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr), X comprises one or more anions, and w, y, and z represent real numbers from 1 to 20. In some embodiments, C may have one or more organic cations. In some embodiments, each organic cation C may be larger than each metal M, and each anion X may be able to bond with both cation C and metal M. In certain embodiments, the perovskite material may have the general formula CMX3.

[0102] In one embodiment, C is ammonium, general formula [NR4] + It may have an organic cation, where the R group may be the same or different. Suitable R groups include, but are not limited to, hydrogen, methyl, ethyl, propyl, butyl, pentyl groups or their isomers; any alkane, alkene, or alkyne CxHy, where x=1~20, y=1~42, cyclic, branched, or linear; alkyl halide, C x H y X zx=1~20, y=0~42, z=1~42, X=F, Cl, Br, or I; any aromatic group (e.g., phenyl, alkylphenyl, alkoxyphenyl, pyridine, naphthalene); cyclic complexes containing at least one nitrogen in the ring (e.g., pyridine, pyrrole, pyrrolidine, piperidine, tetrahydroquinoline); any sulfur-containing group (e.g., sulfoxide, thiol, alkyl sulfide); any nitrogen-containing group (nitroxide, amine); any phosphorus-containing group (phosphate); any boron-containing group (e.g., boronic acid); any organic acid (e.g., acetic acid, propanoic acid); and its ester or amide derivatives; any amino acid having α, β, γ and larger derivatives (e.g., glycine, cysteine, proline, glutamic acid, arginine, serine, histidine, 5-ammoniumvaleric acid); any silicon-containing group (e.g., siloxane); and any alkoxy group or reactive group -OC x H y Here, x = 0 to 20 and y = 1 to 42 are included.

[0103] In one embodiment, C is formamidinium, general formula [R2NCRNR2] + The organic cation is included, where the R group may be the same or different. Suitable R groups include, but are not limited to, hydrogen, methyl, ethyl, propyl, butyl, pentyl groups or their isomers; any alkane, alkene, or alkyne C x H y Here, x = 1 to 20, y = 1 to 42, cyclic, branched, or linear; alkyl halide, C x H y X zx=1~20, y=0~42, z=1=42, X=F, Cl, Br, or I; any aromatic compounds (e.g., phenyl, alkylphenyl, alkoxyphenyl, pyridine, naphthalene); cyclic complexes containing at least one nitrogen in the ring (e.g., imidazole, benzimidazole, pyrimidine, (azolidinylidene methyl)pyrrolidine, triazole); any sulfur-containing groups (e.g., sulfoxide, thiol, alkyl sulfide); any nitrogen-containing groups (nitroxide, amine); any phosphorus-containing groups (phosphate); any boron-containing groups (e.g., boronic acid); any organic acids (acetic acid, propanoic acid) and their esters or amide derivatives; any amino acids having α, β, γ and larger derivatives (e.g., glycine, cysteine, proline, glutamic acid, arginine, serine, histidine, 5-ammoniumvaleric acid); any silicon-containing groups (e.g., siloxane); and any alkoxy or reactive group -OC x H y Here, x = 0 to 20 and y = 1 to 42 are included.

[0104] [ka] Chemical formula 1 is as shown above, [R2NCRNR2] + The structure of a formamidinium cation having the general formula is shown. Chemical formula 2 shows some examples of formamidinium cation structures. This may function as the cation "C" in perovskite materials.

[0105] [ka] In one embodiment, C is guanidium, with the general formula [(R2N)2C=NR2] + It has an organic cation, where the R group may be the same or different groups. Suitable R groups include, but are not limited to, hydrogen, methyl, ethyl, propyl, butyl, pentyl groups or their isomers; any alkane, alkene, or alkyne C x H y(x=1~20, y=1~42, cyclic, branched, or linear); alkyl halide, C x H y X z x=1~20, y=0~42, z=1~42, X=F, Cl, Br, or I; any aromatic group (e.g., phenyl, alkylphenyl, alkoxyphenyl, pyridine, naphthalene); cyclic complexes containing at least one nitrogen in the ring (e.g., octahydropyrimido[1,2-a]pyrimidine, pyrimido[1,2-a]pyrimidine, hexahydroimidazo[1,2-a]imidazole, hexahydropyrimidine-2-imine); any sulfur-containing group (e.g., sulfoxide, thiol, alkylsulfur) Finodes; any nitrogen-containing groups (nitroxides, amines); any phosphorus-containing groups (phosphates); any boron-containing groups (e.g., boronic acids); any organic acids (acetic acid, propanoic acid) and their ester or amide derivatives; any amino acids having α, β, gamma and larger derivatives (e.g., glycine, cysteine, proline, glutamic acid, arginine, serine, histidine, 5-ammoniumvaleric acid); any silicon-containing groups (e.g., siloxanes); and any alkoxy or reactive groups -OC x H y Here, x = 0 to 20 and y = 1 to 42 are included.

[0106] [ka] Chemical formula 3 is, as mentioned above, [(R2N)2C=NR2] + The structure of a guanidium cation having the general formula is shown. Chemical formula 4 shows some examples of guanidium cation structures. This may function as the cation "C" in perovskite materials.

[0107] [ka] TIFF0007866813000005.tif73165 In one embodiment, C is an ethenetetramine cation, with the general formula [(R2N)2C=C(NR2)2] +It may have an organic cation, where the R group may be the same or different reactive group. Suitable R groups include, but are not limited to, hydrogen, methyl, ethyl, propyl, butyl, pentyl groups or their isomers; any alkane, alkene, or alkyne C x H y (x=1~20, y=1~42, cyclic, branched, or linear); alkyl halide, C x H y X z x=1~20, y=0~42, z=1~42, X=F, Cl, Br, or I; any aromatic group (e.g., phenyl, alkylphenyl, alkoxyphenyl, pyridine, naphthalene); cyclic complex containing at least one nitrogen in the ring (e.g., 2-hexahydropyrimidine-2-ylidenehexahydropyrimidine, octahydropyrazine[2,3-b]pyrazine, pyrazino[2,3-b]pyrazine, quinoxalino[2,3-b]quinoxaline); any sulfur-containing group (e.g., sulfoxide, thiol, alkyl sulfide); any nitrogen This includes any phosphorus-containing groups (nitroxides, amines); any phosphorus-containing groups (phosphates); any boron-containing groups (e.g., boric acid); any organic acids (e.g., acetic acid, propanoic acid) and their esters or amide derivatives; any amino acids having α, β, γ and larger derivatives (e.g., glycine, cysteine, proline, glutamic acid, arginine, serine, histidine, 5-ammoniumvaleric acid); any silicon-containing groups (e.g., siloxanes); and any alkoxy or reactive groups, -OCxHy, where x=0 to 20 and y=1 to 42.

[0108] [ka] As mentioned above, chemical formula 5 is [(R2N)2C=C(NR2)2] + The structure of an ethenetetramine cation having the general formula is shown. Chemical formula 6 shows some examples of ethenetetramine ion structures. This may function as the cation "C" in perovskite materials.

[0109] [ka] TIFF0007866813000008.tif85170 In one embodiment, C is an imidazolium cation, general formula [CRNRCRNRCR] + It may have an aromatic cyclic organic cation. Here, the R group may be the same or different groups. Suitable R groups include, but are not limited to, hydrogen, methyl, ethyl, propyl, butyl, pentyl groups or their isomers; alkanes, alkenes or alkynes. x H y (x=1~20, y=1~42, cyclic, branched or linear); alkyl halides, C x H y X z x=1~20, y=0~42, z=1~42, X=F, Cl, Br, or I; any aromatic group (e.g., phenyl, alkylphenyl, alkoxyphenyl, pyridine, naphthalene); cyclic complexes containing at least one nitrogen in the ring (e.g., 2-hexahydropyrimidine-2-ylidenehexahydropyrimidine, octahydropyrazine[2,3-b]pyrazine, pyrazino[2,3-b]pyrazine, quinoxalino[2,3-b]quinoxaline); any sulfur-containing group (e.g., sulfoxide, thiol, alkyl sulfide) ); any nitrogen-containing group (nitroxide, amine); any phosphorus-containing group (phosphate); any boron-containing group (e.g., boric acid); any organic acid (acetic acid, propanoic acid) and ester or amide derivatives; any amino acid having α, β, γ and larger derivatives (e.g., glycine, cysteine, proline, glutamic acid, arginine, serine, histidine, 5-ammoniumvaleric acid); any silicon-containing group (e.g., siloxane); and any alkoxy or reactive group, -OCxHy, where x = 0 to 20, y = 1 to 42.

[0110] [ka] In some embodiments, X may comprise one or more halides. In some embodiments, instead of or in addition to these, X may comprise a Group 16 anion. In some embodiments, the Group 16 anion may be an oxide, sulfide, selenide, or telluride. In some embodiments, instead of or in addition to these, X may comprise one or more pseudohalides (e.g., cyanides, cyanates, isocyanates, fulminates, thiocyans, isothiocyans, azides, tetracarbonylcobaltic acids, carbamoyldicyanomethanides, dicyanonitrosomethanides, dicyanamides, and tricyanomethanides).

[0111] In one embodiment, the perovskite material may have the empirical formula CMX3, where C has one or more cations, group 1 metals, group 2 metals, and / or other cations or cationic compounds, M has one or more metals (e.g., Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr), and X has one or more anions.

[0112] In another embodiment, the perovskite material may have the empirical formula C'M2X6, where C' has a 2+ charged cation, which includes the one or more cations mentioned above, diammonium butane, group 1 metals, group 2 metals, and / or other cations or cationic compounds. M has one or more metals (e.g., Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Ti, Zn, Cd, Hg, and Zr), and X has one or more anions mentioned above.

[0113] In one embodiment, the perovskite material may have the empirical formula C3M2X9, where C comprises one or more cations, Group 1 metals, Group 2 metals, and / or other cations or cationic compounds, M comprises one or more metals (e.g., Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr), and X comprises one or more anions.

[0114] In one embodiment, the perovskite material may have the empirical formula CM2X7, where C has one or more cations, group 1 metals, group 2 metals, and / or other cations or cationic compounds, M has one or more metals (e.g., Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr), and X has one or more anions.

[0115] In one embodiment, the perovskite material may have the empirical formula C2MX4, where C comprises one or more cations, group 1 metals, group 2 metals, and / or other cations or cationic compounds, M comprises one or more metals (e.g., Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr), and X comprises one or more anions.

[0116] Furthermore, perovskite materials have a mixed ion-forming product in which C, M, or X have two or more chemical species, for example, Cs 0.1 FA 0.9 Pb(I 0.9 Cl 0.1 )3;Rb 0.1 FA 0.9 Pb(Cl 0.1 )3, Cs 0.1 FA 0.9PbI3; FAPb 0.5 Sn 0.5 I3; FA 0.83 Cs 0.17 Pb(I 0.6 Br 0.4 )3; FA 0.83 Cs 0.12 Rb 0.05 Pb(I 0.6 Br 0.4 )3 and FA 0.85 MA 0.15 Pb(I 0.85 Br 0.15 )3 may also be included.

[0117] Composite Perovskite Material Device Design In some embodiments, the Disclosure may provide composite designs of PVs and other similar devices (e.g., batteries, hybrid PV batteries, FETs, LEDs, nonlinear optical systems (NLOs), waveguides, etc.) having one or more perovskite materials. For example, one or more perovskite materials may function as either or both of the first and second active materials (e.g., active materials 3906a and 3908a in Figure 3) in some embodiments. More generally, some embodiments of the Disclosure provide PVs or other devices having an active layer comprising one or more perovskite materials. In such embodiments, the perovskite material (i.e., any material having one or more perovskite materials) may be used as the active layer of various architectures. The perovskite material may also function as any one or more components of the active layer (e.g., charge transport material, mesoporous material, photoactive material, and / or interface material, each of which will be discussed in more detail below). In some embodiments, the same perovskite material may contribute to multiple such functions. However, in other embodiments, multiple perovskite materials may be contained in the device, and each perovskite material may perform one or more such functions. In any particular embodiment, whatever role the perovskite material plays, it may be prepared and / or provided in the device in various states. For example, in some embodiments, it may be substantially solid. A solution or suspension may be coated or otherwise deposited within the device (e.g., on another component of the device, such as a mesoporous layer, interface layer, charge transport layer, photoactive layer, or other layer and / or electrode). In some embodiments, the perovskite material may be formed in situ on the surface of another component of the device (e.g., by vapor deposition as a thin-film solid). Any other suitable means may be used to form a layer having the perovskite material.

[0118] Generally, a perovskite material device has a first electrode, a second electrode, and an active layer having a perovskite material, the active layer being located at least in part between the first and second electrodes. In some embodiments, the first electrode may be either an anode or a cathode, and the second electrode may be the other of an anode and a cathode. The active layer according to a particular embodiment may have any one or more active layer members, including charge transport materials, liquid electrolytes, mesoporous materials, photoactive materials (e.g., dies, silicon, cadmium telluride, cadmium sulfide, cadmium selenide, copper indium gallium selenide, gallium arsenide, germanium indium phosphide, semiconductor polymers, other photoactive materials), and interface materials. One or more of these active layer components may have one or more perovskite materials. In some embodiments, some or all of the active layer components may be located in a sublayer, either entirely or partially. For example, the active layer may include any one or more of the following: an interface layer having an interface material, a mesoporous layer having a mesoporous material, and a charge transport layer having a charge transport material. Furthermore, in some embodiments, the interface layer may be included between any two or more other layers of the active layer and / or between the active layer member and the electrode. In this application, reference to a layer includes the final arrangement (e.g., substantially separate portions of each material that can be defined separately within the device), and / or reference to a layer may mean the arrangement during the construction of the device, even with the possibility of subsequent intermixing of the materials in each layer. In some embodiments, the layers may be discrete and have substantially adjacent materials (e.g., the layers may be as stylistically shown in Figure 2).

[0119] In one embodiment, the perovskite material device may be a field-effect transistor (FET). The FET perovskite material device may have a source electrode, a drain electrode, a gate electrode, a dielectric layer, and a semiconductor layer. In one embodiment, the semiconductor layer of the FET perovskite material device may be made of perovskite material.

[0120] A perovskite material device according to one embodiment may include one or more substrates, if necessary. In some embodiments, either or both of the first and second electrodes may be coated or otherwise deposited on the substrate, and the electrodes may be substantially positioned between the substrate and the active layer. In various embodiments, the material of the device composition (e.g., substrate, electrodes, active layer and / or active layer members) may be rigid or flexible, either entirely or partially. In some embodiments, the electrodes may function as the substrate, thereby eliminating the need for another substrate.

[0121] In addition, in certain embodiments, the perovskite material device may include an anti-reflective layer or anti-reflective coating (ARC) if necessary. The perovskite material device may also include any one or more additives, such as any one or more of the additives shown in relation to certain embodiments of this disclosure.

[0122] A description of some of the materials that may be included in the perovskite material device is made in part with reference to Figure 2. Figure 2 is a stylized diagram of a perovskite material device 3900 according to one embodiment. The various components of the device 3900 are shown as separate layers having adjacent materials, but it is understood that Figure 2 is a stylized diagram. Thus, embodiments thereafter may include such separate layers and / or substantially intermixed non-adjacent layers, which is consistent with the use of “layers” described above. The device 3900 has first and second substrates 3901 and 3913. The first electrode 3902 is located on the inner surface of the first substrate 3901, and the second electrode 3912 is located on the inner surface of the second substrate 3913. The active layer 3950 is sandwiched between the two electrodes 3902 and 3912. The active layer 3950 comprises a mesoporous layer 3904, first and second photoactive materials 3906 and 3908, a charge transport layer 3910, and several interface layers. Furthermore, Figure 2 shows an exemplary device 3900 according to an embodiment, in which the sublayers of the active layer 3950 are separated by interface layers, and the interface layers are further arranged on each electrode 3902 and 3912. In particular, the second, third, and fourth interface layers 3905, 3907, and 3909 are arranged between the mesoporous layer 3904, the first photoactive material 3906, the second photoactive material 3908, and the charge transport layer 3910, respectively. The first and fifth interface layers 3903 and 3911 are located (i) between the first electrode 3902 and the mesoporous layer 3904, and (ii) between the charge transport layer 3910 and the second electrode 3912, respectively. Thus, the architecture of the exemplary device shown in Figure 2 is characterized as substrate-electrode-active layer-electrode-substrate. The architecture of the active layer 3950 is characterized as interface layer-mesoporous layer-interface layer-photoactive material-interface layer-photoactive material-interface layer-charge transport layer-interface layer. As described above, in some embodiments, interface layers may not be present, or one or more interface layers may be included, but not all, only in part, between certain active layer components and / or device components.

[0123] The substrates, such as either or both of the first and second substrates 3901 and 3913, may be flexible or rigid. If two substrates are included, at least one must be transparent or translucent to electromagnetic (EM) radiation (e.g., ultraviolet, visible, or infrared). If only one substrate is included, this may also be transparent or translucent, however, this is not required as long as part of the device allows EM radiation to come into contact with the active layer 3950. Suitable substrate materials include any one or more of the following: glass, sapphire, magnesium oxide (MgO), mica, polymers (e.g., PEN, PET, PEG, polyolefin, polypropylene, polyethylene, polycarbonate, PMMA, polyamide, vinylkapton, etc.), ceramics, carbon, composite materials (e.g., glass fiber, Kevlar®, carbon fiber), fabrics (e.g., cotton, nylon, silk, wool), wood, drywall, tiles (e.g., ceramic, composite, or clay), metals, silver, gold, aluminum, magnesium, concrete, and any combination thereof.

[0124] As described above, the electrodes (for example, one of electrodes 3902 and 3912 in Figure 2) may be either an anode or a cathode. In one embodiment, one electrode may function as a cathode and the other as an anode. One or both of electrodes 3902 and 3912 may be coupled to leads, cables, wires, or other means to enable charge transport to and from device 3900. The electrodes are made of any conductive material, and at least one electrode must be transparent or translucent to EM radiation and / or arranged to allow EM radiation to come into contact with at least a portion of the active layer 3950. Suitable electrode materials may include indium tin oxide or tin-doped indium oxide (ITO); fluorine-doped tin oxide (FTO); cadmium oxide (CdO); zinc-indium tin oxide (ZITO); aluminum zinc oxide (AZO); aluminum (Al); gold (Au); silver (Ag); calcium (Ca); chromium (Cr); magnesium (Mg); titanium (Ti); steel; carbon (and their allotropes); doped carbon (e.g., nitrogen-doped); core-shell nanoparticles (e.g., silicon-carbon core-shell structure); and any one or more of these combinations.

[0125] The mesoporous material (for example, the material contained in the mesoporous layer 3904 in Figure 2) may contain any pore-containing material. In one embodiment, the pores may have a diameter in the range of about 1 to about 100 nm. In another embodiment, the pore diameter may be in the range of about 2 to about 50 nm. Suitable mesoporous materials include any interface material and / or mesoporous material discussed elsewhere in this application; aluminum (Al); bismuth (Bi); cerium (Ce); hafnium (Hf); indium (In); molybdenum (Mo); niobium (Nb); nickel (Ni); silicon (Si); titanium (Ti); vanadium (V); zinc (Zn); zirconium (Zr); any one or more oxides of the above metals (e.g., alumina, ceria, titania, zinc oxide, zirconia, etc.); any one or more sulfides of the above metals; any one or more nitrides of the above metals; and any one or more combinations thereof. In one embodiment, any material described in this application as IFL may be a mesoporous material. In another embodiment, the device shown in Figure 2 may not include a mesoporous material layer and may have only a non-mesoporous thin film or a "compact" IFL.

[0126] The photoactive material (e.g., the first or second photoactive material 3906, 3908 in Figure 2) may have any photoactive compound, for example, silicon (e.g., polycrystalline silicon, monocrystalline silicon, or amorphous silicon), cadmium telluride, cadmium sulfide, cadmium selenide, copper indium gallium selenide, copper indium selenide, copper zinc sulfide, gallium arsenide, germanium, germanium indium phosphide, indium phosphide, one or more semiconductor polymers (e.g., polythiophene (poly(3-hexylthiophene)) and its derivatives, or P3HT); polyheptadecanyl carbazole Carbazole copolymers such as thielbenzothiadiazole and its derivatives (e.g., PCDTBT); other copolymers such as polycyclopentadithiophene-benzothiadiazole and its derivatives (e.g., PCPDTBT), polybenzodithiophenyl-thienothiophenediyl and its derivatives (e.g., PTB6, PTB7, PTB7-th, PCE-10); poly(triarylamine) compounds and their derivatives (e.g., PTAA); polyphenylenevinylene and its derivatives (e.g., MDMO-PPV, MEH-PPV), and one or more combinations thereof.

[0127] In some embodiments, the photoactive material may instead or in addition to the photoactive material include a dye (e.g., N719, N3, or other ruthenium-based dyes). In some embodiments, the dye (of some composition) may be coated onto another layer (e.g., a mesoporous layer and / or an interfacial layer). In some embodiments, the photoactive material may include one or more perovskite materials. The perovskite material-containing photoactive material may be in solid form, or in some embodiments, in the form of a dye having a suspension or solution containing the perovskite material. Such a solution or suspension may be coated onto other device components in a similar manner to other dyes. In some embodiments, the solid perovskite-containing material may be deposited by any suitable means (e.g., vapor deposition, solution deposition, direct placement of the solid material, etc.). Devices according to various embodiments may include one, two, three, or more photoactive compounds (e.g., one, two, three, or more perovskite materials, dyes, or combinations thereof). In some embodiments having multiple dyes or other photoactive materials, each of two or more dyes or other photoactive materials may be separated by one or more interfacial layers. In some embodiments, the multiple dyes and / or photoactive compounds may be mixed together, at least partially.

[0128] The charge transport material (e.g., the charge transport material of the charge transport layer 3910 in Figure 2) may include a solid-state charge transport material (i.e., colloquially labeled solid electrolyte) or a liquid electrolyte and / or ionic liquid. Liquid electrolytes, ionic liquids, and solid charge transport materials can all be referred to as charge transport materials. As used in this application, “charge transport material” means any material, solid, liquid, or otherwise capable of collecting and / or transporting charge carriers. For example, in a PV device according to one embodiment, the charge transport material may be capable of transporting charge carriers to electrodes. The charge carriers may have holes (their transport can form a charge transport material, such as a appropriately labeled “hole transport material”) and electrons. Holes are transported toward the anode, electrons toward the cathode, and depending on the arrangement of the charge transport material, they are transported in relation to either the cathode or anode in a PV or other device. Suitable examples of charge transport materials according to one embodiment may include one or more of the following: perovskite materials; I - / I 3-Co complexes; polythiophenes (e.g., poly(3-hexylthiophene) and its derivatives, or P3HT); carbazole copolymers such as polyheptadecanylcarbazole dithienylbenzothiadiazole and its derivatives (e.g., PCDTBT); polycyclopentadithiophene-benzothiadiazole and its derivatives (e.g., PCPDTBT); polybenzodithiophenyl-thienothiophenediyl and its derivatives (e.g., PTB6, PTB7, PTB7-th, PCE-10); poly(triarylamine) compounds and their derivatives (e.g., PTAA); spiro-OMeTAD polyphenylene vinylene and its derivatives (e.g., MDMO-PPV, MEH-PPV); fullerenes and / or fullerene derivatives (e.g., C60, PCBM); carbon nanotubes; graphite; graphene; carbon black; amorphous carbon; glassy carbon; and combinations thereof. In some embodiments, the charge transport material has any solid or liquid material capable of collecting and / or transporting charge carriers (electrons or holes). Therefore, the charge transport material in some embodiments may be an n-type or p-type active, bipolar, and / or intrinsic semiconductor material. The charge transport material may be located in close proximity to one of the electrodes of the device. In some embodiments, it may be located adjacent to an electrode. However, in other embodiments, an interface layer may be located between the charge transport material and the electrode (e.g., having a fifth interface layer 3911 as shown in Figure 2). In certain embodiments, the type of charge transport material may be selected based on the electrode it is adjacent to. For example, if the charge transport material collects and / or transports holes, it may be located in close proximity to the anode and transport holes to the anode. However, the charge transport material may instead be located in close proximity to the cathode and selected or configured to transport electrons to the cathode.

[0129] As described above, devices according to various embodiments may have an interfacial layer between any two other layers and / or materials, if necessary. However, a device according to a particular embodiment is not required to have any interfacial layers. For example, a perovskite material device may include 0, 1, 2, 3, 4, 5, or more interfacial layers (for example, the exemplary device in Figure 2 has five interfacial layers 3903, 3905, 3907, 3909, and 3911). The interfacial layer may have a thin-film coated interfacial layer according to the embodiments described above (for example, having alumina and / or other metal oxide particles, and / or titanium oxide / metal oxide bilayers, and / or other compounds with thin-film coated interfacial layers as described elsewhere). The interfacial layer according to a particular embodiment may have any suitable material and may enhance charge transport and / or collection between the two layers or materials. This may also help to avoid or reduce the possibility of charge recombination once charge has been transported from one of the materials adjacent to the interfacial layer.A suitable interface material may have any one or more of the following: any mesoporous material and / or interface material discussed elsewhere; Ag; Al; Au; B; Bi; Ca; Cd; Ce; Co; Cu; Fe; Ga; Ge; H; In; Mg; Mn; Mo; Nb; Ni; Pt; Sb; Sc; Si; Sn; Ta; Ti; V; W; Y; Zn; Zr; carbides of any of the aforementioned metals (e.g., SiC, Fe3C, WC); the aforementioned Silicides of any metal (e.g., Mg2Si, SrSi2, Sn2Si); oxides of the aforementioned metals (e.g., alumina, silica, titania, SnO2, ZnO); sulfides of the aforementioned metals (e.g., CdS, MoS2, SnS2); nitrides of the aforementioned metals (e.g., Mg3N2, TiN, BN, Si3N4); selenides of the aforementioned metals (e.g., CdSe, FeS2, ZnSe); Tellurides (e.g., CdTe, TiTe2, ZnTe); phosphides of any of the aforementioned metals (e.g., InP, GaP); arsenides of any of the aforementioned metals (e.g., CoAs3, GaAs, InGaAs, NiAs); antimonides of any of the aforementioned metals (e.g., AlSb, GaSb, InSb); halides of any of the aforementioned metals (e.g., CuCl, CuI, BiI3); pseudohalides of any of the aforementioned metals (e.g., CuSCN, AuCN2); carbonates of any of the aforementioned metals (e.g., CaCO3, Ce2(CO3)3); functionalized or unfunctionalized alkylsilyl groups; graphite; graphene; fullerenes; carbon nanotubes; any mesoporous materials and / or interface materials discussed elsewhere; and combinations thereof (in some embodiments, including bilayers, trilayers, or multilayers of combined materials). In some embodiments, the interface layer may have a perovskite material. Furthermore, the interface layer may have doped embodiments of any of the aforementioned interface materials (e.g., Y-doped ZnO, N-doped single-walled carbon nanotubes). Alternatively, the interface layer may have a compound having the three aforementioned elements (e.g., CuTiO3, Zn2SnO4), or a compound having all four aforementioned elements (e.g., CoNiZnO).

[0130] As an example, Figure 3 shows an embodiment of a perovskite material device 3900a having a structure similar to that of the perovskite material device 3900 shown in Figure 2. Figure 3 is a stylized diagram of a perovskite material device 3900a according to one embodiment. It should be noted that Figure 3 is a stylized diagram, although the various components of device 3900a are shown as separate layers with adjacent materials. Thus, this embodiment may have such separate layers and / or substantially intermixed non-adjacent layers, which may be consistent with the use of “layers” described above. Figure 3 has active layers 3906a and 3908a. In one embodiment, one or both of the active layers 3906a and 3908a may contain any perovskite photoactive material shown with respect to Figure 2. In other embodiments, one or both of the active layers 3906a and 3908a may have any photoactive material of the present application, for example, thin-film semiconductors (e.g., CdTe, CZTS, CIGS), photoactive polymers, dye-sensitized photoactive materials, fullerenes, small-molecule photoactive materials, and crystalline and polycrystalline semiconductor materials (e.g., silicon, GaAs, InP, Ge). In yet another embodiment, one or both of the active layers 3906a and 3908a may have a light-emitting diode (LED), a field-effect transistor (FET), a thin-film battery layer, or a combination thereof. In embodiments, one of the active layers 3906a and 3908a may have a photoactive material, and the other may have a light-emitting diode (LED), a field-effect transistor (FET), a thin-film battery layer, or a combination thereof. For example, the active layer 3908a may include a perovskite material photoactive layer, and the active layer 3906b may include a field-effect transistor layer. Other layers shown in Figure 3, such as layers 3901a, 3902a, 3903a, 3904a, 3905a, 3907a, 3909a, 3910a, 3911a, 3912a, and 3913a, may be similar to the corresponding layers described with respect to Figure 2.

[0131] Furthermore, in some embodiments, the perovskite material may have three or more active layers. As an example, Figure 4 shows an embodiment of the perovskite material device 3900b having a structure similar to the perovskite material device 3900 shown in Figure 2. Figure 3 is a stylized diagram of the perovskite material device 3900b according to one embodiment. It should be noted that Figure 4 is a stylized diagram, although the various components of the device 3900b are shown as separate layers having adjacent materials. Thus, this embodiment may have such separate layers and / or substantially intermixed non-adjacent layers, which may be consistent with the use of “layers” described above. Figure 4 has active layers 3904b, 3906b, and 3908b. In some embodiments, one or more of the active layers 3904b, 3906b, and 3908b may have any of the perovskite photoactive materials shown with respect to Figure 2. In other embodiments, one or more of the active layers 3904b, 3906b, and 3908b may have any photoactive material described in this application, for example, thin-film semiconductors (e.g., CdTe, CZTS, CIGS), photoactive polymers, dye-sensitized photoactive materials, fullerenes, small-molecule photoactive materials, and crystalline and polycrystalline semiconductor materials (e.g., silicon, GaAs, InP, Ge). In yet another embodiment, one or more of the active layers 3904b, 3906b, and 3908b may have a light-emitting diode (LED), a field-effect transistor (FET), a thin-film battery layer, or a combination thereof. In an embodiment, one or more of the active layers 3904b, 3906b, and 3908b may have a photoactive material, while the other may have a light-emitting diode (LED), a field-effect transistor (FET), a thin-film battery layer, or a combination thereof. For example, active layers 3908a and 3906b may both have a perovskite material photoactive layer, and active layer 3904b may have a field-effect transistor layer. Other layers shown in Figure 3, such as layers 3901b, 3902b, 3903b, 3904b, 3905b, 3907b, 3909b, 3910b, 3911b, 3912b, and 3913b, may be similar to the corresponding layers described with respect to Figure 2.

[0132] Additional, more specific exemplary embodiments of perovskite devices are discussed in relation to a more stylized description of the device as an example. The stylized nature of these descriptions in Figures 1 to 4 is not intended to limit the type of device. In some embodiments, this may be comprised of one or more of Figures 1 to 4. That is, the architectures described in Figures 1 to 4 may be adapted by any suitable means (including both those expressly shown elsewhere in this application and other preferred means that will be apparent to those skilled in the art who enjoy the benefits of this disclosure) to provide BHJs, batteries, FETs, hybrid PV batteries, serial multicell PVs, parallel multicell PVs, and other similar devices of other embodiments of this disclosure.

[0133] Formation of the active layer in perovskite materials As mentioned above, in one embodiment, the perovskite material in the active layer is of the general formula CMX 3-y X'y (0≧y≧3), where C has one or more cations (e.g., amines, ammonium, group 1 metals, group 2 metals, formamidinium, guanidinium, ethenetetramine, phosphonium, imidazolium, and / or other cations or cationic compounds), M has one or more metals (e.g., Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr), and X and X' have one or more anions. In one embodiment, the perovskite material is CPbI 3-y Cl y It may have the following properties. In one embodiment, the perovskite material may be deposited on a substrate layer as the active layer of a PV device using the following steps, for example, by drop casting, spin casting, slot-die printing, screen printing, or inkjet printing.

[0134] First, a lead halide precursor ink is formed. In a controlled atmosphere (for example, a controlled atmosphere box with a globe-containing port hole, which allows for handling of the material in an air-free environment), a certain amount of lead halide may be assembled in a clean, dry container. Suitable lead halides include, but are not limited to, lead(II) iodide, lead(II) bromide, lead(II) chloride, and lead(II) fluoride. The lead halide may consist of a single type of lead halide or a mixture of lead halides in precise proportions. In some embodiments, the lead halide mixture may have any binary, ternary, or quaternary ratio of iodide, bromide, chloride, or fluoride in 0.001 to 100 mol%. In some embodiments, the lead halide mixture may contain lead(II) chloride and lead(II) iodide in a ratio of about 10 mol:90 mol. In another embodiment, the lead halide mixture may have lead(II) chloride and lead(II) iodide in a ratio of about 5:95, about 7.5:92.5, or about 15 mol:85 mol.

[0135] Alternatively, a precursor ink may be formed using a lead halide salt together with, or instead of, a lead salt precursor. Suitable precursor salts may have any combination of lead(II) or lead(IV) and the following anions: nitrates, nitrites, carboxylates, acetic acid, acetonyl acetonate, formate, oxalate, sulfate, sulfite, thiosulfate, phosphate, tetrafluoroborate, hexafluorophosphate, tetra(perfluorophenyl)borate, hydride, oxide, peroxide, hydroxide, nitride, arsenate, arsenite, perchlorate, carbonate, bicarbonate, chromate, dichromate, iodate, bromate, chlorate, chlorite, hypochlorite, hypobromite, cyanate, cyanide, isocyanate, fulminate, thiocyanate, isothiocyanate, azide, tetracarbonylcobaltate, carbamoyldicyanomethanide, dicyanonitrosomethanide, dicyanamide, tricyanomethanide, amide, and permanganate.

[0136] Furthermore, the precursor ink may contain, as a salt of the anion, 0 to 100% molar ratio of lead(II) or lead(IV) salt with respect to the following metal ions: Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr.

[0137] Next, a solvent may be added to the container, the lead solid may be dissolved, and a lead halide precursor ink may be formed. Suitable solvents may include, but are not limited to, dry N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof. In one embodiment, the lead solid is dissolved in dry dimethylformamide (DMF). The lead solid may be dissolved at a temperature between about 20 and about 150°C. In one embodiment, the lead solid is dissolved at about 85°C. The lead solid is dissolved if necessary to form a solution, which may be done over a period of up to about 72 hours. The resulting solution forms the base of the lead halide precursor ink. In one embodiment, the lead halide precursor ink may have a lead halide concentration of about 0.001 M to about 10 M. In another embodiment, the lead halide precursor ink has a lead halide concentration of about 1 M.

[0138] If necessary, specific additives may be added to the lead halide precursor ink to affect the crystallinity and stability of the final perovskite. In some embodiments, the lead halide precursor ink may further contain amino acids (e.g., 5-aminovaleric acid, histidine, glycine, lysine), amino acid hydrogen halides (e.g., 5-aminovalerate), IFL surface modifiers (SAMs) (e.g., those described above in the specification), or combinations thereof. In some embodiments, formamidinium chloride may be added to the lead halide precursor ink. In other embodiments, any of the aforementioned cationic halides of this application may be used. In some embodiments, a combination of additives may be added to the lead halide precursor ink, including, for example, a combination of formamidinium chloride and 5-aminovalerate.

[0139] For illustrative purposes only and not intended to limit discussion to any specific mechanism theory, formamidinium chloride and 5-aminovaleric acid are recognized to improve the stability of perovskite PV devices when used as additives or countercations in the fabrication of one-step perovskite devices. Furthermore, in the form of PbCl2, chlorides are recognized to improve the performance of perovskite PV devices when added to a PbI2 precursor solution in a two-step process. The two-step perovskite thin film deposition process is recognized to be improved by directly adding formamidinium chloride and / or 5-aminovalerate to a lead halide precursor solution (e.g., PbI2), allowing the benefits of both to be utilized in a single material. Similarly, other perovskite film deposition processes may also be improved by adding formamidinium chloride, 5-aminovalerate, or PbCl2 to a lead halide precursor solution.

[0140] Depending on the desired properties of the resulting perovskite material, additives having formamidinium chloride and / or 5-aminovalerate may be added to the lead halide precursor ink at various concentrations. In one embodiment, the additive may be added at a concentration of about 1 nM to about 1 M. In another embodiment, the additive may be added at a concentration of about 1 μM to about 1 M. In yet another embodiment, the additive may be added at a concentration of about 1 μM to about 1 mM.

[0141] In some embodiments, water may be added to the lead halide precursor ink if necessary. For illustrative purposes only and not intended to limit discussion to any particular mechanism theory, the presence of water affects the crystal growth of perovskite thin films. Under normal conditions, water can be absorbed from the air as vapor. However, the degree of crystallinity of perovskite PV can be controlled by directly adding water to a specific concentration of lead halide precursor ink. Suitable water includes distilled water, deionized water, or other water sources that are substantially free of contaminants (including minerals). Based on photoIV sweeping, it has been observed that the photo-to-power conversion efficiency of perovskite PV is nearly three times higher with the addition of water compared to a completely dry apparatus.

[0142] Depending on the desired properties of the obtained perovskite material, water may be added to the lead halide precursor ink at various concentrations. In one embodiment, water may be added at a concentration of about 1 nL / mL to about 1 mL / mL. In another embodiment, water may be added at a concentration of about 1 μL / mL to about 0.1 mL / mL. In yet another embodiment, water may be added at a concentration of about 1 μL / mL to about 20 μL / mL.

[0143] Next, a lead halide precursor ink may be deposited on a desired substrate. A suitable substrate layer may have any of the substrate layers identified prior to this disclosure. As previously stated, the lead halide precursor ink is deposited by various means, including, but not limited to, drop casting, spin casting, slot die printing, screen printing, or inkjet printing. In certain embodiments, the lead halide precursor ink may be spin-coated onto the substrate at a speed of about 500 rpm to about 10,000 rpm for a period of about 5 seconds to about 600 seconds. In some embodiments, the lead halide precursor ink may be deposited on the substrate at about 3000 rpm for about 30 seconds. The lead halide precursor ink may be deposited on the substrate in an ambient atmosphere with a humidity range of about 0% to about 50% relative humidity. The lead halide precursor ink may then be dried in a substantially water-free atmosphere, i.e., an atmosphere with a relative humidity of less than 30%, to form a thin film.

[0144] Next, the thin film may be thermally annealed at a temperature of about 20°C to about 300°C for a period of up to about 24 hours. In some embodiments, the thin film may be thermally annealed at a temperature of about 50°C for about 10 minutes. The perovskite material active layer may then be completed by a conventional process. In this case, the precursor film is immersed in or rinsed in a solution containing a solvent or a mixture of solvents (e.g., DMF, isopropanol, methanol, ethanol, butanol, chloroform chlorobenzene, dimethyl sulfoxide, water) and a salt (e.g., methylammonium iodide, formamidinium iodide, guanidinium iodide, 1,2,2-triaminovinylammonium iodide, 5-aminovaleric acid hydroiodide) at a concentration between 0.001 M and 10 M. In some embodiments, the thin film may also be thermally post-annealed in the same manner as in the first line of this paragraph.

[0145] In one embodiment, a lead salt precursor may be deposited on a substrate to form a lead salt thin film. The substrate may have a temperature approximately equal to the ambient temperature, or a controlled temperature between 0°C and 500°C. The lead salt precursor is deposited by various conventional methods, including, but not limited to, spin coating, slot die printing, inkjet printing, gravure printing, screen printing, sputtering, PE-CVD, thermal deposition, or spray coating. The deposition of the lead salt precursor may be carried out in various atmospheres, at atmospheric pressure (e.g., about 1 atmosphere, depending on altitude and atmospheric conditions) or at a pressure lower than atmospheric pressure (e.g., 1 mTorr to 500 mTorr). The deposition atmosphere may be ambient air, a controlled humidity environment (e.g., 0-100 g of H2O / m³ of gas). 3 ), may include pure argon, pure nitrogen, pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO2, or any combination of the aforementioned gases. The controlled humidity environment may have an environment in which the absolute humidity or % relative humidity is maintained at a fixed value, or an environment in which the absolute humidity or % relative humidity changes according to a predetermined setpoint or predetermined function. In certain embodiments, the installation may be carried out in a controlled humidity environment having a % relative humidity of 0% or more and 50% or less. In other embodiments, the installation may be 0 g H2O / m 3 Gas or more, 20g H2O / m³ 3 This may be carried out in a controlled humidity environment below the gas level.

[0146] The lead salt precursor may be a liquid, gas, solid, or a combination of these states, such as a solution, suspension, colloid, foam, gel, or aerosol. In some embodiments, the lead salt precursor may be a solution containing one or more solvents. For example, the lead salt precursor may have one or more of the following: N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof. The lead salt precursor may include a single lead salt (e.g., lead(II) iodide, lead(II) thiocyanate) or any combination disclosed herein (e.g., PbI2 + PbCl2; PbI2 + Pb(SCN)2). The lead salt precursor may also contain one or more additives such as amino acids (e.g., 5-aminovaleric acid hydroiodide), 1,8-diiodooctane, 1,8-dithiooctane, formamidinium halide, acetic acid, trifluoroacetic acid, methylammonium halide, or water. The lead halide precursor ink is dried in a substantially water-free atmosphere, i.e., an atmosphere with a relative humidity of less than 30%, to form a thin film. The thin film may then be thermal annealed at a temperature of about 20°C to about 300°C for a period of up to about 24 hours. Annealing may be carried out in various atmospheres at ambient pressure (e.g., about 1 atmosphere, depending on altitude and atmospheric conditions), or at atmospheric pressure or a pressure lower than ambient (e.g., 1 mTorr to 500 mTorr). The annealing atmosphere may be ambient air, a controlled humidity environment (e.g., 0-100 g of H2O / m³ gas). 3), may have pure argon, pure nitrogen, pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO2, or any combination of the aforementioned gases. The controlled humidity environment may have an environment in which the absolute humidity or % relative humidity is maintained at a constant value, or an environment in which the absolute humidity or % relative humidity changes according to a predetermined set value or predetermined function. In certain embodiments, annealing may be performed in a controlled humidity environment having a % relative humidity of 0% or more and 50% or less. In other embodiments, annealing may be performed 0g H2O / m 3 The above gases, and 20g H2O / m³ 3 This may be carried out in a controlled humidity environment containing the following gases.

[0147] After the lead salt precursor is set, a second salt precursor (e.g., formamidinium iodide, formamidinium thiocyanate, or guanidinium thiocyanate) may be deposited on the lead salt thin film. Here, the lead salt thin film may have a temperature approximately equal to the ambient temperature, or a controlled temperature between 0°C and 500°C. In some embodiments, the second salt precursor may be deposited at ambient temperature or at a high temperature between approximately 25°C and 125°C. The second salt precursor may be deposited by various conventional methods, including, but not limited to, spin coating, slot die printing, inkjet printing, gravure printing, screen printing, sputtering, PE-CVD, thermal deposition, or spray coating. The setting of the second salt precursor may be carried out in various atmospheres at ambient pressure (e.g., approximately 1 atmosphere, depending on altitude and atmospheric conditions), or at atmospheric pressure or a pressure lower than ambient pressure (e.g., 1 mTorr to 500 mTorr). The deposition atmosphere is the ambient air, a controlled humidity environment (e.g., 0-100g of H2O / m³ of gas). 3), may include pure argon, pure nitrogen, pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO2, or any combination of the aforementioned gases. The controlled humidity environment may include an environment in which the absolute humidity or % relative humidity is maintained at a constant value, or an environment in which the absolute humidity or % relative humidity changes according to a predetermined set point or predetermined function. In certain embodiments, deposition may be carried out in a controlled humidity environment having a % relative humidity of 0% or more and 50% or less. In other embodiments, deposition may be carried out in an environment with 0 g H2O / m³ 3 More than 20g H2O / m 3 This may be carried out in a controlled humidity environment containing the following gases.

[0148] In one embodiment, the second salt precursor may be a solution containing one or more solvents. For example, the second salt precursor may contain one or more of the following: dried N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof.

[0149] After deposition of the lead salt precursor and the second salt precursor, the substrate may be annealed. By annealing the substrate, the lead salt precursor and the second salt precursor may be converted into perovskite materials (e.g., FAPbI3, GAPb(SCN)3, FASnI3). Annealing may be carried out in various atmospheres at ambient pressure (e.g., about 1 atmosphere, depending on altitude and atmospheric conditions), or at atmospheric pressure or a pressure lower than ambient pressure (e.g., 1 mTorr to 500 mTorr). The annealing atmosphere may be ambient air, a controlled humidity environment (e.g., 0-100 g of H2O / m³ gas). 3), may have pure argon, pure nitrogen, pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO2, or any combination of the aforementioned gases. The controlled humidity environment may include an environment in which the absolute humidity or % relative humidity is maintained at a constant value, or an environment in which the absolute humidity or % relative humidity changes according to a predetermined setpoint or predetermined function. In certain embodiments, annealing may be performed in a controlled humidity environment having a relative humidity of 0% or more and 50% or less. In other embodiments, annealing may be performed at 0 g H2O / m³ 3 More than 20g H2O / m 3 The process may be carried out in a controlled humidity environment containing the following gases. In some embodiments, the annealing may be carried out at a temperature between 50°C and 300°C. Unless otherwise stated, any annealing or deposition step described herein may be carried out under the aforementioned conditions.

[0150] For example, in certain embodiments, the FAPbI3 perovskite material may be formed by the following process. First, a lead(II) halide precursor having a molar ratio of PbI2 to PbCl2 of about 90:10 dissolved in anhydrous DMF may be deposited on a substrate by spin coating or slot die printing. The lead halide precursor ink may be dried for about 1 hour (±15 minutes) in a substantially water-free atmosphere, i.e., an atmosphere with a relative humidity of less than 30%, to form a thin film. Next, the thin film may be thermal annealed for about 10 minutes at a temperature of about 50°C (±10°C). In other embodiments, the lead halide precursor may be deposited by inkjet printing, gravure printing, screen printing, sputtering, PE-CVD, atomic layer deposition, thermal evaporation, or spray coating. Next, a formamidinium iodide precursor having formamidinium iodide at a concentration of 25-60 mg / mL dissolved in anhydrous isopropyl alcohol may be deposited on the lead halide thin film by spin coating or slot die printing. In other embodiments, the formamidinium iodide precursor may be deposited by inkjet printing, gravure printing, screen printing, sputtering, PE-CVD, atomic layer deposition, thermal deposition, or spray coating. After depositing the lead halide precursor and the formamidinium iodide precursor, a relative humidity of about 25% (about 4-7 g of H2O / m³) is maintained. 3 The substrate may be annealed in air and at a temperature between approximately 125°C and 200°C to form a formamidinium lead iodide (FAPbI3) perovskite material.

[0151] In another embodiment, the perovskite material may have C'CPbX3, where C' is one or more group 1 metals (i.e., Li, Na, K, Rb, Cs). In a particular embodiment, M' may be cesium (Cs). In another embodiment, C' may be rubidium (Rb). In another embodiment, C' may be sodium (Na). In yet another embodiment, C' may be potassium (K). In yet another embodiment, the perovskite material has C' v C w Pby X z The perovskite material may have, where C' is one or more Group 1 metals, and v, w, y, and z represent real numbers between 1 and 20. In certain embodiments, the perovskite material may be deposited on a substrate layer as an active layer using the steps described below, for example, by drop casting, spin casting, gravure coating, blade coating, reverse gravure coating, slot die printing, screen printing, or inkjet printing.

[0152] First, a lead halide solution is formed. In a controlled atmosphere, a certain amount of lead halide is contained in a clean, dry container. Suitable lead halides include, but are not limited to, lead(II) iodide, lead(II) bromide, lead(II) chloride, and lead(II) fluoride. The lead halide may consist of a single type of lead halide or a mixture of lead halides in precise proportions. In some embodiments, the lead halide may contain lead(II) iodide. In certain embodiments, the lead halide mixture may have any binary, ternary, or quaternary ratio of iodide, bromide, chloride, or fluoride in 0.001 to 100 mol%. In some embodiments, the lead halide mixture may contain lead(II) chloride and lead(II) iodide in a ratio of about 10:90 mol. In another embodiment, the lead halide mixture may contain lead(II) chloride and lead(II) iodide in molar ratios of about 5:95, about 7.5:92.5, or about 15:85.

[0153] Alternatively, a lead salt precursor may be used, either together with or instead of a lead halide, to form a lead salt solution. Suitable precursor lead salts may have any combination of lead(II) or lead(IV) and the following anions: nitrates, nitrites, carboxylates, acetic acids, formates, oxalates, oxalates, sulfates, sulfites, thiosulfates, phosphates, tetrafluoroborates, hexafluorophosphates, tetra(perfluorophenyl)borates, hydrides, oxides, peroxides, hydroxides, nitrides, arsenates, arsenites, perchlorates, carbonates, bicarbonates, chromates, dichromates, ioates, bromates, chlorates, chlorites, hypochlorites, hypobromites, cyanides, cyanates, cyanides, isocyanates, fulminates, thiocyanates, isothiocyanates, azides, tetracarbonylcobaltates, carbamoyldicyanomethanides, dicyanonitrosomethanides, dicyanomethanides, tricyanomethanides, amides, and permanganates.

[0154] The lead salt solution may further contain, as a salt of the above anion, lead(II) salt or lead(IV) salt in a molar ratio of 0 to 100% with respect to the following metal ions: Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, Pb, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr.

[0155] Next, a solvent may be added to the container and the lead halide solid may be dissolved to form a lead halide solution. Suitable solvents include, but are not limited to, dry N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide (DMF), dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof. In one embodiment, the lead solid is dissolved in dry dimethylformamide (DMF). The lead halide solid may be dissolved at a temperature of about 20°C to about 150°C. In one embodiment, the lead halide solid is dissolved at about 85°C. The lead halide solid may be dissolved if necessary to form a solution, and this may be done over a period of up to about 72 hours. The resulting solution forms the base of a lead halide precursor ink. In some embodiments, the lead halide precursor ink may have a lead halide concentration of about 0.001 M to about 10 M. In some embodiments, the lead halide precursor ink may have a lead halide concentration of about 1 M. In some embodiments, the lead halide solution may further contain amino acids (e.g., 5-aminovaleric acid, histidine, glycine, lysine), amino acid hydrogen halides (e.g., 5-aminovaleric acid salts), IFL surfactants (SAMs) (e.g., those described in the specification), or combinations thereof.

[0156] Next, a Group 1 metal halide solution is formed. A certain amount of the Group 1 metal halide is contained in a clean, dry container under a controlled atmosphere. Suitable Group 1 metal halides may include, but are not limited to, cesium iodide, cesium bromide, cesium chloride, cesium fluoride, rubidium iodide, rubidium bromide, rubidium chloride, rubidium fluoride, lithium iodide, lithium bromide, lithium chloride, lithium fluoride, sodium iodide, sodium bromide, sodium chloride, sodium fluoride, potassium iodide, potassium bromide, potassium chloride, and potassium fluoride. The Group 1 metal halide may consist of a single type of Group 1 metal halide or a mixture of Group 1 metal halides in precise proportions. In one embodiment, the Group 1 metal halide may include cesium iodide. In another embodiment, the Group 1 metal halide may include rubidium iodide. In another embodiment, the Group 1 metal halide may include sodium iodide. In yet another embodiment, the Group 1 metal halide may include potassium iodide.

[0157] Alternatively, a Group 1 metal salt solution may be formed using a Group 1 metal halide salt together with, or instead of, another Group 1 metal salt precursor. A suitable precursor Group 1 metal salt may have any combination of a Group 1 metal and any of the following anions: nitrates, nitrites, carboxylates, acetic acids, formates, oxalates, sulfates, sulfites, thiosulfates, phosphates, tetrafluoroborates, hexafluorophosphates, tetra(perfluorophenyl)borates, hydrides, oxides, peroxides, hydroxides, nitrides, arsenates, arsenites, perchlorates, carbonates, bicarbonates, chromates, iodates, bromates, chlorates, chlorites, hypochlorites, hypobromites, cyanates, cyanides, isocyanates, fulminates, thiocyanates, isothiocyanates, azides, tetracarbonylcobaltates, carbamoyldicyanomethanides, dicyanonitrosomethanides, dicyanonemethanides, tricyanomethanides, amides, and any combination of permanganates.

[0158] Next, a solvent may be added to the container, and the Group 1 metal halide solid may dissolve to form a Group 1 metal halide solution. Suitable solvents include, but are not limited to, dry N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide (DMF), dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof. In some embodiments, the lead solid is dissolved in dry dimethyl sulfoxide (DMSO). The Group 1 metal halide solid may dissolve at a temperature between about 20 and about 150°C. In some embodiments, the Group 1 metal halide solid is dissolved at room temperature (i.e., about 25°C). The Group 1 metal halide solid may be dissolved if necessary to form a solution, which may be done over a period of up to about 72 hours. The resulting solution forms a Group 1 metal halide solution. In some embodiments, the Group 1 metal halide solution may have a Group 1 metal halide concentration between about 0.001 M and about 10 M. In some embodiments, the Group 1 metal halide solution has a Group 1 metal halide concentration of about 1 M. In some embodiments, the Group 1 metal halide solution may further contain amino acids (e.g., 5-aminovaleric acid, histidine, glycine, lysine), amino acid hydrohalides (e.g., 5-aminovalerate salts), IFL surface modifiers (SAMs) (e.g., those described in the specification), or combinations thereof.

[0159] Next, the lead halide solution and the Group 1 metal halide solution are mixed to form a thin film precursor ink. The lead halide solution and the Group 1 metal halide solution may be mixed in a ratio such that the resulting thin film precursor ink has a molar concentration of Group 1 metal halides between 0% and 25% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides of 1% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides of 5% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides of 10% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides of 15% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides of 20% of the molar concentration of lead halide. In certain embodiments, the thin-film precursor ink may have a molar concentration of Group 1 metal halide that is 25% of the molar concentration of lead halide. In some embodiments, the lead halide solution and the Group 1 metal halide solution may be stirred during or after mixing.

[0160] Next, a thin film precursor ink may be deposited on a desired substrate. Suitable substrate layers may include any substrate layers identified above. As previously stated, the thin film precursor ink may be deposited by various means, including, but not limited to, drop casting, spin casting, gravure coating, blade coating, reverse gravure coating, slot die printing, screen printing, or inkjet printing. In certain embodiments, the thin film precursor ink may be spin-coated onto the substrate at a speed of about 500 rpm to about 10,000 rpm for a time of about 5 seconds to about 600 seconds. In one embodiment, the thin film precursor ink may be spin-coated onto the substrate at about 3000 rpm for about 30 seconds. The thin film precursor ink may be deposited onto the substrate in an ambient atmosphere with a humidity range of about 0% relative humidity to about 50% relative humidity. Next, the thin film precursor ink may be deposited in a substantially water-free atmosphere, i.e., with a relative humidity of less than 30%, or 7 g H2O / m². 3 It may be dried in less than a certain time, and a thin film may be formed.

[0161] Next, the thin film may be thermally annealed at a temperature of about 20°C to about 300°C for a period of up to about 24 hours. In some embodiments, the thin film may be thermally annealed at a temperature of about 50°C for about 10 minutes. The conversion process then completes the perovskite material active layer. In this case, the precursor film is immersed in or rinsed in a salt solution containing a solvent or a mixture of solvents (e.g., DMF, isopropanol, methanol, ethanol, butanol, chloroform chlorobenzene, dimethyl sulfoxide, water) and a salt at a concentration between 0.001 M and 10 M (e.g., methylammonium iodide, formamidinium iodide, guanidinium iodide, 1,2,2-triaminovinylammonium iodide, 5-aminovaleric acid hydroiodide). In some embodiments, the perovskite material thin film may also be thermally post-annealed in the same manner as in the first line of this paragraph.

[0162] In one embodiment, a salt solution may be prepared by collecting the salt in a clean, dry container under a controlled environmental atmosphere. Suitable salts include, but are not limited to, methylammonium iodide, formamidinium iodide, guanidinium iodide, imidazolium iodide, ethenetetramineioiodide, 1,2,2-triaminovinylammonium iodide, and 5-aminovaleric acid hydroiodide. Other suitable salts may have any organic cations listed in the chapter "Perovskite Materials". The salt may consist of a single type of salt or a mixture of salts in precise proportions. In one embodiment, the salt may contain methylammonium iodide. In another embodiment, the salt may contain formamidinium iodide. A solvent may then be added to the container, the salt solid may be dissolved, and a salt solution may be formed. Suitable solvents include, but are not limited to, DMF, isopropanol, methanol, ethanol, butanol, chloroform chlorobenzene, dimethyl sulfoxide, water, and combinations thereof. In one embodiment, a formamidinium iodide salt solid is dissolved in isopropanol. The salt solid may be dissolved at a temperature between about 20 and about 150°C. In one embodiment, the salt solid is dissolved at room temperature (i.e., about 25°C). The salt solid may be dissolved if necessary to form a solution, and this may be done over a period of up to about 72 hours. The resulting solution forms a salt solution. In one embodiment, the salt solution may have a salt concentration of about 0.001 M to about 10 M. In one embodiment, the salt solution has a salt concentration of about 1 M.

[0163] For example, using the method described above, Cs i A perovskite material having the general formula MAPbI3 may be obtained, where i is a number between 0 and 1. As another example, a lead(II) iodide solution, a rubidium iodide solution, and a formamidinium(FA) iodide salt solution may be used to obtain a perovskite material having the general formula Rb iA perovskite material having FAPbI3 may be obtained, where i is equal to a number between 0 and 1. As another example, using a lead(II) iodide solution, a cesium iodide solution, and a formamidinium (FA) iodide salt solution, Cs i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1. As another example, using lead(II) iodide solution, potassium iodide solution, and formamidinium (FA) iodide salt solution, the general formula K i A perovskite material having FAPbI3 may be obtained, where i is a number between 0 and 1. As another example, using a lead(II) iodide solution, a sodium iodide solution, and a formamidinium (FA) iodide salt solution, Na i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1. As another example, using a lead(II) iodide lead-chloride(II) mixed solution, a cesium iodide solution, and a formamidinium (FA) salt solution, Cs i FAPbI 3-y Cl y A perovskite material having the following general formula may be obtained: where i is a number between 0 and 1, and y is a number between 0 and 3.

[0164] In certain embodiments, the lead halide solution described above may have a molar ratio of PbI2 to PbCl2 of 90:10. A cesium iodide (CsI) solution may be added to the lead halide solution by the method described above to form a thin-film precursor ink containing 10 mol% CsI. The FAPbI3 perovskite material may be produced using this thin-film precursor solution by the method described above. As described above, when cesium ions are added via the CsI solution, chloride anions and cesium atoms are incorporated into the FAPbI3 crystal lattice. In this case, the degree of lattice contraction may be greater compared to the case where cesium or rubidium ions are added without the addition of chloride ions, as described above. Table 1 below shows the lattice parameters of FAPbI3 perovskite materials with 10 mol% rubidium and 20 mol% chloride (e.g., 10 mol% PbCl2), 10 mol% cesium, and 10 mol% cesium with 20 mol% chloride. Here, the mol% concentration represents the concentration of the additive relative to the lead atoms in the lead halide solution. As seen in Table 1, the FAPbI3 perovskite materials with added cesium and chloride have smaller lattice parameters than the other two perovskite material samples.

[0165] [Table 1] Furthermore, the data showed that FAPbI3 perovskite materials doped with rubidium, cesium, and / or chloride possessed a Pm3-m cubic structure. FAPbI3 perovskites with 10 mol% Rb and 10 mol% Cl, or 10 mol% Cs, or 10 mol% Cs and 10 mol% Cl were observed to maintain a cubic Pm3-m cubic structure. Figure 29 shows the X-ray diffraction patterns corresponding to each sample shown in Table 1. Tables 2-4 show the X-ray diffraction peaks and intensities for the three perovskite materials shown in Table 1. Data were collected under ambient conditions using a Rigaku Miniflex 600 with a CuKα radiation source at a scanning speed of 1.5°²θ / min.

[0166] [Table 2]

[0167] [Table 3]

[0168] [Table 4] Table 5 shows the geometrically predicted X-ray diffraction patterns of cubic Pm3-m materials with a lattice constant of 6.3375 angstroms under Cu-Kα radiation. As can be seen from the data, each of the perovskite materials prepared with 10 mol% Rb and 10 mol% Cl, 10 mol% Cs, and 10% Cs and 10% Cl exhibits diffraction patterns consistent with those expected for cubic Pm3-m perovskite materials.

[0169] [Table 5] (Enhanced Perovskite) So-called "layered" 2D perovskites are known to form when the perovskite is formed with organic cations having longer alkyl chains than the aforementioned methylammonium and formamidinium cations. Layered 2D perovskites have structures such as the rudolsdene-popper phase, the Dion-Jacobson phase, and the Aurivillius phase. For example, by substituting 1-butylammonium for methylammonium or the other aforementioned cations, a rudolsdene-popper 2D perovskite is produced during perovskite formation in a "one-step" method (not described herein). In such perovskites, 1-butylammonium prevents the perovskite from forming a complete crystal lattice, and instead, the perovskite is formed in a "sheet" of perovskite having the thickness of a single crystal structure. Figure 5 shows the structure of rudolsdene-popper 5500, which has a 1-butylammonium cation 5510. As can be seen in Figure 5, the "tail" of the butylammonium cation causes separation between the lead and iodide portions of the perovskite material and the other lead and iodide structures, resulting in a "sheet" of 2D perovskite. Therefore, the introduction of "bulky" organic cations such as 1-butylammonium or benzylammonium during the formation of the perovskite material is undesirable if the rudrudsdene-popper morph of the perovskite is not desired.

[0170] However, if a diluted amount of 1-butylammonium solution is added before annealing the perovskite material, a perovskite may be formed as shown in Figure 6. Figure 6 shows an embodiment of perovskite material 2000 to which alkylammonium cations have been added for surface passivation. In the shown embodiment, the surface of formamidinium lead iodide (FAPbI3) perovskite material 2010 is shown to have 1-butylammonium cations 2020 on its surface. In some embodiments, 1-butylammonium cations, or other "bulky" organic cations, may diffuse into the perovskite material near the surface of the crystal lattice of the perovskite material. In certain embodiments, 1-butylammonium cations, or other "bulky" organic cations described herein, may be located within 50 nm or less of the crystal lattice surface or grain boundaries in the perovskite material. The inclusion of a "bulky" organic cation, such as 1-butylammonium, on or near the surface of the perovskite material can result in a general formula for the perovskite material that deviates from the "ideal" stoichiometry of the perovskite material described herein. For example, the inclusion of such an organic cation may result in the perovskite material having a general formula that is either quasi-stoichiometric or hyperstoichiometric with respect to the CMX3 formula described herein. In this case, the general formula for the perovskite material is C x M y X z It may also be expressed as follows: where x, y, and z are real numbers. In one embodiment, the perovskite material is given by the general formula C'2C n-1 M n X 3n-1 It may have the formula C'2MX4, where n is an integer. For example, when n=1, the perovskite material has the general formula C'2CM2X7, when n=2, the perovskite material has the general formula C'2CM2X7, and when n=3, the perovskite material has the formula C'2C2M3X 10 Having the following characteristics, if n=4, the perovskite material is given by the general formula C'2C3M4X 13 The same applies hereafter. As shown in Figure 30, the n value indicates the thickness of the inorganic metal halide sublattice of the perovskite material. General formula C'2C n-1M n X 3n-1 Phases of perovskite materials having bulky organic cations may be formed in regions where bulky organic cations are diffused or introduced into the crystal lattice of the perovskite material. For example, such phases may be located within 50 nanometers of the crystal lattice surface (e.g., surface or grain boundary) of the perovskite material having bulky organic cations described in this application.

[0171] The carbon "tail" of the 1-butylammonium ion can provide protective properties to the perovskite surface by effectively keeping other molecules away from the surface. In some embodiments, the alkyl "tail" of the 1-butylammonium ion may be oriented away from the surface of the perovskite material or parallel to the surface of the perovskite material. In particular, the "tail" of 1-butylammonium may have hydrophobic properties, thereby preventing water molecules from coming into contact with the perovskite surface and protecting the surface of the perovskite material 2010 from moisture in the environment. The 1-butylammonium cation may also act to passivate the surface and grain boundaries or defects of the perovskite material 2010. Passivation refers to electrical properties that prevent charge accumulation, or "trapped state," at the surface or grain boundaries of the perovskite material 2010. By acting to passivate a portion of the perovskite material 2010, charge transfer to and from the perovskite material 2010 in 1-butylammonium can be improved, thereby improving the electrical properties of the photoactive layer.

[0172] In some embodiments, other organic cations may be applied instead of or in combination with 1-butylammonium. Examples of other “bulky” organic cations that can act on surface passivated perovskite materials include, but are not limited to, ethylammonium, propylammonium, n-butylammonium; perylene n-butylamine-imide; butane-1,4-diammonium; 1-pentylammonium; 1-hexylammonium; poly(vinylammonium); phenylethylammonium; 3-phenyl-1-propylammonium; 4-phenyl-1-butylammonium; 1,3-dimethylbutylammonium; 3,3-dimethylbutylammonium; 1-heptylammonium; 1-octylammonium; 1-nonylammonium; 1-decylammonium; and 1-icosanylammonium. In addition, in bulky organic cations having a tail containing one or more heteroatoms in addition to the cationic species, the heteroatoms may coordinate, bond, or integrate with the crystal lattice of the perovskite material. The heteroatoms may be any atom in the tail that is not hydrogen or carbon, including nitrogen, sulfur, oxygen, or phosphorus.

[0173] Other examples of "bulky" organic cations may include the following molecules functionalized with ammonium groups, phosphonium groups, or other cationic groups integrated into the surface C-site of perovskite materials: benzene, pyridine, naphthalene, anthracene, xanthene, phenathrene, tetracenechrysene, tetrafen, benzo[c]phenathrene, triphenylene, pyrene, perylene, coronene, substituted dicarboxylate imides, aniline, N-(2-aminoethyl)-2-isoindole-1,3-di On, 2-(1-aminoethyl)naphthalene, 2-triphenylene-O-ethylamine, benzylamine, benzylammonium salt, Nn-butyl-N'-4-aminobutylperylene-3,4,9,10-bis(dicarboximide), 1-(4-alkylphenyl)methaneamine, 1-(4-alkyl-2-phenyl)methaneamine, 1-(4-alkylphenyl)methaneamine, 1-(3-alkyl-5-alkylphenyl)methaneamine, 1-(3-alkyl-5-alkyl-2-phenyl) Nyl)ethanamine, 1-(4-alkyl-2-phenyl)ethanamine, 2-ethylamine-7-alkyl-naphthalene, 2-ethylamine-6-alkyl-naphthalene, 1-ethylamine-7-alkyl-naphthalene, 1-ethylamine-6-alkyl-naphthalene, Nn-aminoalkyl-N'-4-aminobutylperylene-3,4,9,10-bis(dicarboximide), 1-(3-butyl-5-methoxybutylphenyl)methaneamine, 1-(4-pentylphenyl)methaneamine N, 1-[4-(2-methylpentyl)-2-phenyl]ethaneamine, 1-(3-butyl-5-pentyl-2-phenyl)ethaneamine, 2-(5-[4-methylpentyl]-2-naphthyl)ethaneamine, N-7-tridecyl-N'-4-aminobutylperylene-3,4,9,10-bis(dicarboximide), Nn-heptyl-N'-4-aminobutylperylene-3,4,9,10-bis(dicarboximide), 2-(6-[3-methoxylpropyl]-2-naphthyl)ethaneamine. Figures 17 to 28 show the structures of these organic molecules according to specific embodiments. With respect to Figures 17 and 18, each "R group" xR can be any of H, R', Me, Et, Pr, Ph, Bz, F, Cl, Br, I, NO2, OR', NR'2, SCN, CN, N3, or SR', where R' may be any alkyl, alkenyl, or alkynyl chain. Also, the shown R x At least one of the elements is (CH2) n EX y or (CH2) n C(EX y) may also be 2, where n and y = 0, 1, 2 or more, and n and y may be equal or different. Furthermore, with respect to Figure 19, the shown molecules may have any hydrohalide salt of each shown amine, for example, benzylammonium salt, where the shown X group may be F, Cl, Br, I, SCN, CN, or any other pseudohalide. Other non-halogenated anions include nitrates, nitrites, carboxylates, acetates, acetonyl acetonates, formates, oxalates, sulfates, sulfites, thiosulfates, phosphates, tetrafluoroborates, hexafluorophosphates, tetra(perfluorophenyl)borates, hydrides, oxides, peroxides, hydroxides, nitrides, arsenates, arsenites, perchlorates, carbonates, bicarbonates, chromates, dichromates, iodates, bromates, chlorates, hypochlorites, chlorites, hypobromites, cyanides, cyanates, isocyanates, fulminates, thiocyanates, isothiocyanates, azides, tetracarbonylcobaltates, carbamoyl dicyanonemethanide, dicyanonitrosometamide, dicyanonemethanide, tricyanomethanide, amides, and permanganates.Furthermore, preferred R groups include, but are not limited to, hydrogen, methyl, ethyl, propyl, butyl, pentyl groups or their isomers; alkanes, alkenes or alkynes CxHy, where x=1-20, y=1-42, cyclic, branched or linear; alkyl halides, CxHyXz, where x=1-20, y=0-42, z=1-42, X=F, Cl, Br, or I; any aromatic group (e.g., phenyl, alkylphenyl, alkoxyphenyl, pyridine, naphthalene); cyclic complexes containing at least one nitrogen in the ring (e.g., pyridine, pyrrole, pyrrolidine, piperidine, tetra Hydroquinoline; any sulfur-containing group (e.g., sulfoxide, thiol, alkyl sulfide); any nitrogen-containing group (nitrooxide, amine); any phosphorus-containing group (e.g., boronic acid); any organic acid (e.g., acetic acid, propanoic acid); and its ester or amide derivatives; any amino acid having α, β, γ and larger derivatives (e.g., glycine, cysteine, proline, glutamic acid, arginine, serine, histidine, 5-ammoniumvaleric acid); any silicon-containing group (e.g., siloxane); and any alkoxy or -OCxHy group, where x = 0 to 20 and y = 1 to 42.

[0174] In some embodiments, bulky organic cations may also passivate grain boundaries and surface defects in the perovskite material. Figure 7 shows an example of a perovskite material layer 3000. 1-butylammonium 3020 may form a hydrophobic layer that repels water and other polar species, preventing such chemical species from reaching the surface of the perovskite material. As shown in Figure 7, the "tails" of the bulky organic cations do not have to be chemically bonded (e.g., covalently or ionically) to the surface or grain boundaries 3015 of the perovskite material layer 3000. For example, the tail of 1-butylammonium is a butyl group, and the tail of benzylammonium is a benzyl group.

[0175] The tails of bulky organic cations may be assumed to have other configurations with respect to the surface or grain boundaries of the perovskite material. Generally, the cationic "head" of a bulky organic cation does not diffuse beyond 50 nanometers across the surface or grain boundaries of the perovskite material. The tails interact weakly with the perovskite material and are oriented away from the perovskite material grain surface. The tails may also exhibit intermolecular interactions (e.g., dipole-dipole or hydrogen bonds) with the perovskite material grain surface, resulting in a configuration in which the tails are oriented toward the perovskite material grain surface. In some embodiments, the tails of certain bulky organic cations present in the perovskite material may not interact with the surface or grain boundaries of the perovskite material, while the tails of other bulky organic cations in the perovskite material may interact with the surface or grain boundaries of the perovskite material. The tail has a heteroatom or anion (i.e., a zwitterion) having at least one lone pair of electrons, which may covalently interact with the grain surface of the perovskite material via metal atoms (e.g., Pb, Sn, Ge, In, Bi, Cu, Ag, Au) present in the perovskite material (i.e., coordination covalent bond). Alternatively, the tail may have a cationic species such as diammonium butane as described herein, which may be incorporated into the perovskite material by substitution on at least two "C" cationic sites (e.g., formamidinium). Furthermore, the cationic tail may bridge two layers of the 2D perovskite material, tilt across the grain surface of the perovskite material, or be oriented away from the grain surface of the perovskite material in a manner similar to that described with respect to nonionic tails. In another embodiment, bulky organic cations having a sufficiently large tail, such as imidazolium cations, may not be diffused into the perovskite material but may simply be present on the perovskite surface or grain boundaries.

[0176] In other embodiments, bulky organic cations having tail groups of varying length or size may be applied to the perovskite to passivate grain boundaries and surface defects in the perovskite material. Figure 8 shows an exemplary embodiment of the perovskite material layer 4000. A combination of 1-butylammonium 4020, 1-nonylammonium 4021, 1-heptylammonium 4022, and 1-hexylammonium 4023 passivates both the surface and grain boundaries 4015 of the bulk perovskite material 4010. In specific embodiments, any mixture of the aforementioned identified alkylammonium compounds may be applied to the perovskite material described herein. Figure 8 shows an exemplary embodiment of the perovskite material layer 4000. A combination of 1-butylammonium 4020, 1-nonylammonium 4021, 1-heptylammonium 4022, and 1-hexylammonium 4023 passivates both the surface and grain boundaries 4015 of the bulk perovskite material 4010. In certain embodiments, any mixture of the aforementioned identified alkylammonium compounds may be applied to the perovskite material described herein. In some embodiments, the bulky organic cation may have a benzyl group. Figure 8A shows an embodiment as an example of a perovskite material layer 4500. Various bulky organic cations having a benzyl group passivate both the surface and grain boundaries 4515 of the bulk perovskite material 4510.

[0177] As previously mentioned, it has been shown that adding a 1-butylammonium surface coating to perovskite materials increases the high-temperature durability of perovskites in humid environments. Figure 9 shows a comparison of images of perovskite materials with and without a 1-butylammonium ("BAI") surface coating over 48 days. Both perovskite materials had the same composition and were exposed to a temperature environment of 85°C and a relative humidity of 55% for 48 days. As can be seen from the photographs, the perovskite material without the 1-butylammonium surface coating became significantly lighter in color after 1 day of exposure to the environment, indicating significant degradation of the perovskite material. The perovskite material with the 1-butylammonium surface coating gradually lightened in color over 48 days, with some dark areas remaining even after 48 days. This indicates that the perovskite material with the 1-butylammonium surface coating is more robust than the perovskite material without the 1-butylammonium surface coating during long-term exposure to high-temperature environments.

[0178] Figure 10 shows a comparison of images of perovskite materials over 7 days with and without a 1-butylammonium ("BAI") surface coating. Both perovskite materials had the same composition and were exposed to a temperature environment of 85°C at 0% relative humidity for 7 days. As can be seen from the photographs, the perovskite material without the 1-butylammonium surface coating became significantly lighter in color after 1 day of exposure to the environment, indicating significant degradation of the perovskite material. The perovskite material with the 1-butylammonium surface coating showed almost no color change even after 7 days. This indicates that the perovskite material with the 1-butylammonium surface coating was not completely damaged during long-term exposure to a high-temperature, high-humidity environment.

[0179] In another embodiment, as previously described with respect to 1-butylammonium, perylene n-butylamine-imide may be applied to the surface of the perovskite material. Figures 11A-D show various perylene monoimides and diimides that may be applied to the surface of perovskite materials according to this disclosure. Figure 12 shows an embodiment of perovskite material 2500 in which alkylammonium cations are added for surface passivation. In the shown embodiment, it is shown that the surface of formaminium lead iodide (FAPbI3) perovskite material 2510 has surface perylene n-butylamine-imide 2520. Similar to 1-butylammonium shown in Figure 6, the carbon "tail" of the perylene n-butylamine-imide ion may have protective properties on the perovskite surface by effectively detaching other molecules from the surface. In particular, the perylene n-butylamine-imide "tail" has hydrophobic properties, which prevents water molecules from coming into contact with the perovskite surface, thus protecting the surface of the perovskite material 2510 from moisture in the environment. The perylene n-butylamine-imide cation may also act to passivate the surface of the perovskite material 2510 and any grain boundaries or defects. By acting to passivate a portion of the perovskite material 2510, the perylene n-butylamine-imide may improve charge transfer to and from the perovskite material 2510, thereby improving the electrical properties of the photoactive layer.

[0180] The following describes a method for depositing 1-butylammonium before annealing perovskite materials.

[0181] First, a lead halide precursor ink is formed. In a controlled atmosphere environment (for example, a controlled atmosphere box with a glove-containing porthole allows for manipulation of the material in an airless environment), a certain amount of lead halide may be collected in a clean, dry container. Suitable lead halides include, but are not limited to, lead(II) iodide, lead(II) bromide, lead(II) chloride, and lead(II) fluoride. The lead halide may consist of a single type of lead halide or a mixture of lead halides in precise proportions. In certain embodiments, the lead halide mixture may have any binary, ternary, or quaternary ratio of iodide, bromide, chloride, or fluoride in 0.001 to 100 mol%. In some embodiments, the lead halide mixture may contain lead(II) chloride and lead(II) iodide in a ratio of about 10:90 mol:mol. In another embodiment, the lead halide mixture may contain lead(II) chloride and lead(II) iodide in a mol:mol ratio of about 5:95, about 7.5:92.5, or about 15:85.

[0182] Alternatively, other lead salt precursors may be used together with or instead of lead halide to form a precursor ink. Suitable precursor salts may have any combination of lead(II) or lead(IV) and the following anions: nitrates, nitrites, carboxylates, acetic acid, acetonyl acetonate, formate, oxalate, sulfate, sulfite, thiosulfate, phosphate, tetrafluoroborate, hexafluorophosphate, tetra(perfluorophenyl)borate, hydride, oxide, peroxide, hydroxide, nitride, arsenate, arsenite, perchlorate, carbonate, bicarbonate, chromate, dichromate, iodate, bromate, chlorate, chlorite, hypochlorite, hypobromite, cyanide, cyanate, isocyanate, fulminate, thiocyanate, isothiocyanate, azide, tetracarbonylcobaltate, carbamoyldicyanomethanide, dicyanonitrosomethanide, dicyanamide, tricyanomethanide, amide, and permanganate.

[0183] The precursor ink may further contain, as a salt of the above anion, a salt of lead(II) or lead(IV) in a molar ratio of 0 to 100% with respect to the following metal ions: Be, Mg, Ca, Sr, Ba, Fe, Cd, Co, Ni, Cu, Ag, Au, Hg, Sn, Ge, Ga, In, Tl, Sb, Bi, Ti, Zn, Cd, Hg, and Zr.

[0184] Next, a solvent may be added to dissolve the lead solid, forming a lead halide precursor ink. Suitable solvents include, but are not limited to, dry N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof. In one embodiment, the lead solid is dissolved in dry dimethylformamide (DMF). The lead solid can be dissolved at a temperature of about 20 to about 150°C. In one embodiment, the lead solid is dissolved at about 85°C. The lead solid can be dissolved for as long as necessary to form a solution, which may be done over a maximum of about 72 hours. The resulting solution forms the base of the lead halide precursor ink. In one embodiment, the lead halide precursor ink may have a lead halide concentration of about 0.001 M to about 10 M. In another embodiment, the lead halide precursor ink has a lead halide concentration of about 1 M.

[0185] If necessary, additives in the lead halide precursor ink may be added to affect the crystallinity and stability of the final perovskite. In certain embodiments, the lead halide precursor ink may further include amino acids (e.g., 5-aminovaleric acid, histidine, glycine, lysine), amino acid hydrogen halides (e.g., 5-aminovaleric acid hydrochloride), IFL surface modification (SAM) agents (e.g., those described above in the specification), or combinations thereof. In certain embodiments, formamidinium chloride may be added to the lead halide precursor ink. In other embodiments, halides of any of the aforementioned cations of the present application may be used. In certain embodiments, an additive having a combination of, for example, formamidinium chloride and 5-aminovaleric acid hydrochloride may be added to the lead halide precursor ink.

[0186] Additives containing formamidinium chloride and / or 5-aminovaleric acid hydrochloride may be added to the lead halide precursor ink at various concentrations depending on the desired properties of the resulting perovskite material. In certain embodiments, the additive may be added at a concentration of about 1 nM to about 1 M. In another embodiment, the additive may be added at a concentration of about 1 μM to about 1 M. In another embodiment, the additive may be added at a concentration of about 1 μM to about 1 mM.

[0187] In certain embodiments, a halide solution of a Group 1 metal is formed and added to the lead halide precursor ink. An amount of the Group 1 metal halide is collected in a clean and dry container under a controlled atmosphere environment. Suitable Group 1 metal halides include, but are not limited to, cesium iodide, cesium bromide, cesium chloride, cesium fluoride, rubidium iodide, rubidium bromide, rubidium chloride, rubidium fluoride, lithium iodide, lithium bromide, lithium chloride, lithium fluoride, sodium iodide, sodium bromide, sodium chloride, sodium fluoride, potassium iodide, potassium bromide, potassium chloride, potassium fluoride. The Group 1 metal halide may have a single species of the Group 1 metal halide, or may have a mixture of Group 1 metal halides in an exact ratio. In certain embodiments, the halide of the Group 1 metal may have cesium iodide. In another embodiment, the halide of the Group 1 metal may have rubidium iodide. In another embodiment, the halide of the Group 1 metal may have sodium iodide. In another embodiment, the halide of the Group 1 metal may include potassium iodide.

[0188] Alternatively, other Group 1 metal salt precursors may be used together with or instead of the Group 1 metal halide salt to form a Group 1 metal salt solution. Suitable precursor Group 1 metal salts may have a combination of any Group 1 metal and the following anions: nitrate, nitrite, carboxylate, acetate, formate, oxalate, sulfate, sulfite, thiosulfate, phosphate, tetrafluoroborate, hexafluorophosphate, tetra(perfluorophenyl)borate, hydride, oxide, peroxide, hydroxide, nitride, arsenate, arsenite, perchlorate, carbonate, bicarbonate, chromate, iodate, bromate, chlorate, chlorite, hypochlorite, hypobromite, cyanide, cyanate, isocyanate, fulminate, thiocyanate, isothiocyanate, azide, tetracarbonylcobaltate, carbamoyldicyanomethanide, dicyanonitrosomethanide, dicyanonomethanide, tricyanonomethanide, amide, and permanganate.

[0189] Next, a solvent may be added to the container, and the Group 1 metal halide solid may dissolve to form a Group 1 metal halide solution. Suitable solvents include, but are not limited to, dry N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide (DMF), dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof. In some embodiments, the lead solid is dissolved in dry dimethyl sulfoxide (DMSO). The Group 1 metal halide solid may dissolve at a temperature of about 20 to about 150°C. In some embodiments, the Group 1 metal halide solid dissolves at room temperature (i.e., about 25°C). The Group 1 metal halide solid may dissolve for up to about 72 hours, if necessary to form a solution. The resulting solution forms a Group 1 metal halide solution. In some embodiments, the Group 1 metal halide solution may have a Group 1 metal halide concentration between about 0.001 M and about 10 M. In some embodiments, the Group 1 metal halide solution has a Group 1 metal halide concentration of about 1 M. In some embodiments, the Group 1 metal halide solution may further contain amino acids (e.g., 5-aminovaleric acid, histidine, glycine, lysine), amino acid hydrohalides (e.g., 5-aminovalerate salts), IFL surface modifiers (SAMs) (e.g., those described above in the specification), or combinations thereof.

[0190] Next, the lead halide solution and the Group 1 metal halide solution are mixed to form a thin film precursor ink. The lead halide solution and the Group 1 metal halide solution may be mixed in a ratio such that the resulting thin film precursor ink has a molar concentration of Group 1 metal halides between 0% and 25% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides corresponding to 1% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides corresponding to 5% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides corresponding to 10% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides corresponding to 15% of the molar concentration of lead halide. In certain embodiments, the thin film precursor ink may have a molar concentration of Group 1 metal halides corresponding to 20% of the molar concentration of lead halide. In certain embodiments, the thin-film precursor ink may have a molar concentration of Group 1 metal halide equivalent to 25% of the molar concentration of lead halide. In some embodiments, the lead halide solution and the Group 1 metal halide solution may be stirred during or after mixing.

[0191] In some embodiments, water may be added to the lead halide precursor ink if necessary. For illustrative purposes only and without limiting disclosure to any particular theory or mechanism, the presence of water affects the crystal growth of perovskite thin films. Under normal conditions, water can be absorbed from the air as vapor. However, at certain concentrations, the degree of crystallinity of perovskite PV can be controlled by directly adding water to the lead halide precursor ink. Suitable water includes distilled water, deionized water, or any other water source that is substantially free of contaminants (including minerals). Based on optical IV scanning, it has been observed that the photo-to-power conversion efficiency of perovskite PV is nearly three times higher with the addition of water compared to a completely dry apparatus.

[0192] Water may be added to the lead halide precursor ink at various concentrations depending on the desired properties of the resulting perovskite material. In one embodiment, water may be added at a concentration of about 1 nL / mL to about 1 mL / mL. In another embodiment, water may be added at a concentration of about 1 μL / mL to about 0.1 mL / mL. In yet another embodiment, water may be added at a concentration of about 1 μL / mL to about 20 μL / mL.

[0193] Next, the lead halide precursor ink or thin film precursor ink may be deposited on a desired substrate. A suitable substrate layer may have any substrate layer known prior to this disclosure. As previously stated, the lead halide precursor ink or thin film precursor ink may be deposited by various means, but not limited to, drop casting, spin casting, slot die printing, screen printing, or inkjet printing. In certain embodiments, the lead halide precursor ink or thin film precursor ink may be spin-coated onto the substrate at a speed of about 500 rpm to about 10000 rpm over a period of about 5 seconds to about 600 seconds. In one embodiment, the lead halide precursor ink or thin film precursor ink may be spin-coated onto the substrate at about 3000 rpm for about 30 seconds. In some embodiments, multiple subsequent depositions of the precursor ink may be performed to form a thin film layer. The lead halide precursor ink or thin film precursor ink may be deposited onto the substrate in an ambient atmosphere with a relative humidity range of about 0% to about 50%. Next, the lead halide precursor ink or thin film precursor ink may be dried in a substantially water-free atmosphere, i.e., an atmosphere with a relative humidity of less than 30%, to form a thin film.

[0194] After deposition of the lead halide precursor or thin film precursor, a salt solution of one of the aforementioned bulky organic cations (e.g., benzylammonium, phenylethylammonium, ethylammonium, propylammonium, n-butylammonium; butane-1,4-diammonium; 1-pentylammonium; 1-hexylammonium; poly(vinylammonium); phenylethylammonium; 3-phenyl-1-propylammonium; 4-phenyl-1-butylammonium; 1,3-dimethylbutylammonium; 3,3-dimethylbutylammonium; 1-heptylammonium; 1-octylammonium; 1-nonylammonium; 1-decylammonium; 1-icosanylammonium; or any other bulky cation described in this application or shown in Figures 17 to 28) may be placed in the thin film, resulting in the deposition of the lead salt precursor and the second salt precursor. Bulky organic salts may include halides, nitrates, nitrites, carboxylates, acetates, acetonyl acetonates, formates, oxalates, sulfates, sulfites, thiosulfates, phosphates, tetrafluoroborates, hexafluorophosphates, tetra(perfluorophenyl)borates, hydrides, oxides, peroxides, hydroxides, nitrides, arsenides, arsenates, perchlorates, carbonates, bicarbonates, chromates, dichromates, iodates, bromates, chlorates, chlorites, hypochlorites, hypobromites, cyanides, cyanates, isocyanates, fulminates, thiocyanates, isothiocyanates, azides, tetracarbonylcobaltates, carbamoyl dicyanonemethanides, dicyanonitrosometanides, dicyanamides, tricyanomethanides, amides, and / or any permanganates of the aforementioned cations.A bulky organic cation salt solution may be formed by dissolving the bulky organic cation salt in a solvent such as alcohol, dry N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide (DMF), dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof. In certain embodiments, the bulky organic cation salt may be dissolved in isopropyl alcohol. In certain embodiments, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of 0.0001 M to 1.0 M. In other embodiments, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of 0.01 M to 0.1 M. In certain embodiments, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of 0.02 to 0.05 M. In certain embodiments, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of about 0.05 M. The bulky organic cation salt solution may be deposited on a perovskite material precursor thin film by any method described in this application with respect to solution deposition. These methods may include spray coating, drop casting, spin casting, slot die printing, screen printing, gravure printing, or inkjet printing. In some embodiments, the bulky organic cation salt may be 1-butylammonium iodide. In another embodiment, the bulky organic cation salt may be benzylammonium iodide. In yet another embodiment, the bulky organic cation salt may be phenylethylammonium iodide.

[0195] Next, the thin film may be thermally annealed at a temperature of about 20°C to about 300°C for up to about 24 hours. In some embodiments, the thin film may be thermally annealed at a temperature of about 50°C for about 10 minutes. Next, the conversion process may complete the perovskite material active layer. In the conversion process, the precursor film is immersed or rinsed with a solution containing a solvent or mixture of solvents (e.g., DMF, isopropanol, methanol, ethanol, butanol, chloroform chlorobenzene, dimethyl sulfoxide, water) and a salt (e.g., methylammonium iodide, formamidinium iodide, guanidinium iodide, 1,2,2-triaminovinylammonium iodide, 5-aminovalerate) at a concentration of 0.001 M to 10 M. In some embodiments, the thin film may also be thermally post-annealed in the same manner as in the first line of this paragraph.

[0196] In some embodiments, after a thin film is deposited and annealed, a second salt precursor (e.g., formamidinium iodide, formamidinium thiocyanate, or guanidinium thiocyanate) may be deposited on the lead salt thin film. Here, the thin film may have a temperature approximately equal to the ambient temperature, or a controlled temperature between 0°C and 500°C. The second salt precursor may be deposited at ambient temperature or at a heated temperature of about 25°C to 125°C. The second salt precursor may be formed by various conventionally known methods, including, but not limited to, spin coating, slot die printing, inkjet printing, gravure printing, screen printing, sputtering, PE-CVD, thermal deposition, or spray coating. In some embodiments, multiple subsequent depositions of the second salt solution may be carried out to form a thin film layer. In some embodiments, the second salt precursor may be a solution containing one or more solvents. For example, the second salt precursor may include one or more of the following: dried N-cyclohexyl-2-pyrrolidone, alkyl-2-pyrrolidone, dimethylformamide, dialkylformamide, dimethyl sulfoxide (DMSO), methanol, ethanol, propanol, butanol, tetrahydrofuran, formamide, tert-butylpyridine, pyridine, alkylpyridine, pyrrolidine, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, and combinations thereof.

[0197] In some embodiments, any bulky organic cation salt described herein may be combined with a second salt solution before deposition of the second salt solution. In some embodiments, the bulky organic cation salt solution may be prepared as described above and mixed with the second salt solution before deposition of the second salt solution. For example, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of 0.0001 M to 1.0 M. In another embodiment, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of 0.01 M to 0.1 M. In some embodiments, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of 0.02 to 0.05 M. In a particular embodiment, the bulky organic cation salt solution may have a bulky organic cation salt at a concentration of about 0.05 M. In other embodiments, the bulky organic cation salt solution may be deposited on a lead halide thin film formed after deposition of a lead halide precursor ink or thin film precursor ink. In another embodiment, a bulky organic cation salt solution may be deposited on the perovskite precursor thin film after the deposition of the second salt solution.

[0198] Finally, the substrate having the perovskite material precursor thin film may be annealed. By annealing the substrate, the lead salt precursor and the second salt precursor may be converted into a perovskite material (e.g., FAPbI3, GAPb(SCN)3, FASnI3) having a bulky organic cation surface passivation layer. The annealing process may be carried out in various atmospheres at ambient pressure (e.g., about 1 atmosphere (760 Torr) depending on altitude and atmospheric conditions), or at atmospheric pressure or below ambient pressure (e.g., 1 mTorr to 500 mTorr). The annealing atmosphere may be ambient air, a controlled humidity environment (e.g., 0 to 100 g of H2O / m³ of gas). 3The controlled humidity environment may consist of pure argon, pure nitrogen, pure oxygen, pure hydrogen, pure helium, pure neon, pure krypton, pure CO2, or any combination of the aforementioned gases. The controlled humidity environment may be an environment in which the absolute humidity or % relative humidity is maintained at a fixed value, or an environment in which the absolute humidity or % relative humidity changes according to a predetermined setpoint or predetermined function. In certain embodiments, the annealing process may be carried out in a controlled humidity environment having a relative humidity of 0% to 50%. In other embodiments, the annealing process may be carried out in an environment with a relative humidity of 0g H2O / m³. 3 More than 20g H2O / m 3 The process may be carried out in a controlled humidity environment containing the following gases. In one embodiment, the annealing process may be carried out at a temperature between 50°C and 300°C.

[0199] For example, in certain embodiments, the FAPbI3 perovskite material may be formed by the following process: First, a lead(II) halide precursor containing PbI2 to PbCl2 in a molar ratio of about 90:10 dissolved in anhydrous DMF is deposited onto the substrate by spin coating, blade coating, or slot die printing. In a substantially water-free atmosphere, i.e., with a relative humidity of less than 30% or H2O / m³, the material is deposited. 3In an atmosphere of less than 17 g, the lead halide precursor ink is dried for about 1 hour (±15 minutes) to form a thin film. Next, the thin film may be thermally annealed for about 10 minutes at a temperature of about 50°C (±10°C). In other embodiments, the lead halide precursor may be deposited by inkjet printing, gravure printing, screen printing, sputtering, PE-CVD, atomic layer deposition, thermal evaporation, or spray coating. Next, a solution of 1-butylammonium salt having a concentration of 0.05 M in isopropyl alcohol may be deposited on the lead halide thin film. Next, a formamidinium iodide precursor having formamidinium iodide at a concentration of 15-100 mg / mL dissolved in anhydrous isopropyl alcohol may be deposited on the lead halide thin film by spin coating or blade coating. In other embodiments, the formamidinium iodide precursor may be deposited by inkjet printing, gravure printing, screen printing, slot die printing, sputtering, PE-CVD, atomic layer deposition, thermal evaporation, or spray coating. Next, relative humidity of approximately 25% (approximately 4-7g of H2O / m³) 3 The substrate is annealed between approximately 100 and 200°C (with gas), forming a formamidinium lead iodide (FAPbI3) perovskite material having a 1-butylammonium surface layer. In another embodiment, the 1-butylammonium salt solution may be deposited on a thin film formed after the deposition of the formamidinium iodide precursor. In yet another embodiment, the 1-butylammonium salt solution may be combined with the lead halide precursor ink before the deposition of the lead halide precursor ink. In yet another embodiment, the 1-butylammonium salt solution may be combined with the formamidinium iodide precursor before the deposition of the formamidinium iodide precursor. In yet another embodiment, the 1-butylammonium salt solution may be deposited on the thin film after the deposition of the formamidinium iodide precursor and before the thin film and substrate are annealed. In yet another embodiment, the 1-butylammonium salt solution may be deposited on the thin film after the thin film and substrate are annealed.

[0200] In other embodiments, lead(II) iodide solution, cesium iodide solution, methylammonium (MA) salt solution, and 1-butylammonium salt solution are used, and Cs is produced by the method described above. i A perovskite material having the general formula MAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is 1-butylammonium. As another example, using lead(II) iodide solution, rubidium iodide solution, formamidinium(FA) iodide salt solution, and 1-butylammonium salt solution, Rb i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a 1-butylammonium layer. As another example, using a lead(II) iodide solution, a cesium iodide solution, a formamidinium (FA) iodide salt solution, and a 1-butylammonium salt solution, Cs can be obtained by the method described above. i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a 1-butylammonium layer. As another example, using lead(II) iodide solution, potassium iodide solution, formamidinium (FA) iodide salt solution, and 1-butylammonium salt solution, K i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a 1-butylammonium layer. As another example, using lead(II) iodide solution, sodium iodide solution, formamidinium (FA) iodide salt solution, and 1-butylammonium salt solution, Na i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a 1-butylammonium layer. As another example, lead(II) iodide lead-chloride(II) mixture, cesium iodide solution, formamidinium(FA) iodide salt solution, and 1-butylammonium salt solution may be used to obtain Cs i FAPbI 3-y Cl yA perovskite material having the general formula can be obtained, where i is equal to a number between 0 and 1, y is a number between 0 and 3, and the surface layer is a 1-butylammonium layer.

[0201] In another embodiment, the FAPbI3 perovskite material may be formed by the following method: First, a lead halide precursor ink in which PbI2 is dissolved in anhydrous DMF in a molar ratio of about 90:10 to PbCl2 may be deposited onto the substrate by spin coating, blade coating, or slot die printing. The lead halide precursor ink is deposited in a substantially water-free atmosphere, i.e., with a relative humidity of less than 30% or less than 17 g of H2O / m³. 3 The film may be dried in an atmosphere for about 1 hour (±15 minutes) to form a thin film. The thin film may then be heat-annealed at a temperature of about 50°C (±10°C) for about 10 minutes. In other embodiments, the lead halide precursor may be deposited by inkjet printing, gravure printing, screen printing, sputtering, PE-CVD, atomic layer deposition, thermal evaporation, or spray coating. Next, a formamidinium iodide precursor having formamidinium iodide dissolved in anhydrous isopropyl alcohol at a concentration of 15-60 mg / mL may be deposited on the lead halide thin film by spin coating or blade coating. In other embodiments, the formamidinium iodide precursor may be deposited by inkjet printing, gravure printing, screen printing, slot die printing, sputtering, PE-CVD, atomic layer deposition, thermal evaporation, or spray coating. After depositing lead halide precursors and formamidinium iodide precursors, a benzyl ammonium salt solution having a concentration of 0.04 M in isopropyl alcohol may be deposited on the perovskite material precursor thin film. Next, the substrate is subjected to a relative humidity of about 25% (about 4-7 g of H2O / m²). 3The material may be annealed between approximately 100 and 200°C (with gas) to form a formamidinium iodide lead (FAPbI3) perovskite material along with a benzylammonium surface layer. In certain embodiments, the benzylammonium salt solution may be deposited on a lead halide thin film before the deposition of the formamidinium iodide precursor. In another embodiment, the benzylammonium salt solution may be combined with a lead halide precursor ink before the deposition of the lead halide precursor ink. In yet another embodiment, the benzylammonium salt solution may be combined with a formamidinium iodide precursor before the deposition of the formamidinium iodide precursor. In some embodiments, the resulting perovskite material may have a cubic structure in the bulk material away from the surface. If bulky organic cations are present near the surface of the perovskite material, a non-cubic structure may be formed near the surface of the perovskite material.

[0202] In other embodiments, lead(II) iodide solution, cesium iodide solution, methylammonium (MA) salt solution, and 1-butylammonium salt solution are used in the process described above to produce Cs i A perovskite material having the general formula MAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a benzylammonium layer. As another example, using lead(II) iodide solution, rubidium iodide solution, formamidinium(FA) iodide salt solution, and benzylammonium salt solution, Rb may be obtained by the aforementioned process. i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a benzylammonium layer. As another example, using lead(II) iodide solution, cesium iodide solution, formamidinium (FA) iodide salt solution, and benzylammonium salt solution, Cs can be obtained by the aforementioned process. iA perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a benzylammonium layer. As another example, using a lead(II) iodide solution, a potassium iodide solution, a formamidinium (FA) iodide salt solution, and a benzylammonium salt solution, the above process may be used to obtain K i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a benzylammonium layer. As another example, using lead(II) iodide solution, sodium iodide solution, formamidinium (FA) iodide salt solution, and benzylammonium salt solution, Na can be obtained by the aforementioned process. i A perovskite material having the general formula FAPbI3 may be obtained, where i is equal to a number between 0 and 1, and the surface layer is a benzylammonium layer. As another example, using a lead(II) iodide-lead(II) chloride mixture, a cesium iodide solution, a formamidinium (FA) iodide salt solution, and a benzylammonium salt solution, Cs can be obtained by the aforementioned process. i FAPbI 3-y Cl y A perovskite material having the following formula may be obtained: where i is equal to a number between 0 and 1, y is a number between 0 and 3, and the surface layer is a benzylammonium layer.

[0203] The following describes a method for producing perovskite materials using benzylammonium. First, a lead iodide precursor ink is prepared by dissolving PbI2, PbCl2, and cesium iodide (CsI) in a mixture of DMF and DMSO solvents. To prepare the lead iodide precursor, a 1.5 M CsI / DMSO solution is prepared by dissolving CsI in DMSO. In certain embodiments, the CsI / DMSO solution may be prepared by stirring CsI in DMSO at a ratio of 1.5 mmol CsI / 1.0 mL anhydrous DMSO for 1 to 2.5 hours at room temperature. Next, the aforementioned CsI solution is added to a solution of PbI2, PbCl2, and anhydrous DMF solvent to form a 1.28 M Pb 2+A solution is formed. The ratio of Cs to Pb is 1:10, and the ratio of I to Cl is 9:1. In one embodiment, 1.28 M Pb 2+ The solution may also be prepared by adding the CsI solution to 93.8 μL of each CsI solution in a container containing 1.26 mmol of PbI2, 0.14 mmol of PbCl2, and 1.0 mL of anhydrous DMF solvent. 2+ The solution is mixed at a temperature of 50°C to 100°C for 1.5 to 2.5 hours before cooling to form a lead iodide precursor ink. In certain embodiments, Pb 2+ The solution may be cooled by stirring at 85°C for 2 hours, followed by stirring at room temperature for 1 hour. In some embodiments, the lead iodide precursor ink may be filtered before deposition of the lead iodide precursor ink. In certain embodiments, a 0.2 μm filter may be used to filter the lead iodide precursor ink.

[0204] Formamidinium iodide (FAI) and benzylammonium iodide (BzAI) salts are dissolved in anhydrous isopropanol (IPA) to prepare formamidinium iodide (FAI) and benzylammonium iodide (BzAI) solutions, forming a 0.2 M FAI solution and a 0.05 M BzAI solution, respectively. In certain embodiments, both the FAI and BzAI solutions may be kept at 75°C during the following coating process.

[0205] Next, a lead iodide precursor ink is deposited onto a substrate and then annealed to form a lead iodide film. In certain embodiments, the lead iodide precursor ink, held at 45°C, may be blade-coated onto a substrate coated with a thin nickel oxide (NiO) film layer, and then annealed at 50°C for 10 minutes to form a lead iodide film.

[0206] Next, to form the perovskite material layer, the lead iodide film is first primed with one coat of BzAI solution, followed by three coats of FAI solution. Following the deposition of each coating of BzAI and FAI solution, the coating is dried and the subsequent coatings are deposited. In certain embodiments, both the BzAI and FAI solutions may be held at 45°C during the deposition of each respective coating. After the deposition of the third FAI coating, the substrate and coating may be annealed to form the perovskite material layer. In certain embodiments, after the deposition of the third FAI, the substrate is immediately heated at 157°C for 5 minutes to anneal the perovskite material layer.

[0207] The aforementioned method may have several advantages. For example, by depositing a BzAI solution on a lead iodide film before depositing the FAI solution, an intermediate template may be provided for the growth of a 3D FAPbI3 perovskite material by forming a 2D perovskite material. BzAI may react with the lead iodide thin film to form an intermediate 2D perovskite material phase. If BzAI reacts with FAI after the deposition of the FAI solution, BzA in the 2D phase may be formed. + Cation is FA +The cations are completely or partially replaced, forming a 3D FAPbI3 framework. Additionally, BzAI may passivate crystalline defects within the 3D FAPbI3 perovskite material. The photoluminescence intensity of the FAPbI3 thin film formed by the aforementioned process is brighter (higher) than that of the FAbI3 thin film formed by a process without BzAI. Figure 31 shows optical (absorbance) and photoluminescence images of both the perovskite material photovoltaic device 3105 formed without the addition of BzAI and the perovskite material photovoltaic device 3110 formed using the aforementioned BzAI. Figure 31 shows that the optical image of the perovskite material photovoltaic device 3110 is darker, suggesting higher light absorbance, and that the photoluminescence image of the perovskite material photovoltaic device 3110 is brighter than that of the perovskite material photovoltaic device 3105. Furthermore, it has been observed that the power output is greater from perovskite material photovoltaics incorporating BzAI. Figure 32 shows the power output curve 3205 corresponding to a photovoltaic that does not include BzAI, such as photovoltaic 3105, and the power output curve 3210 corresponding to a photovoltaic that includes BzAI, such as photovoltaic 3110 described in this application. The power output measurements shown in Figure 32 are 100 mW / cm² over 180 seconds, with a 30-second dark state measurement intervening, to show steady-state characteristics. 2 Measurements are taken at the maximum power point under AM1.5G illumination. As can be seen from Figure 32, photovoltaic devices with BzAI incorporated during manufacturing are compared to photovoltaic devices without BzAI (15.0 mW / cm²). 2 770mV and 19.5mA / cm² 2 In comparison, the power per unit area (16.0 mW / cm²) 2 ), voltage (785mV), and current per unit area (20.3mA / cm²) 2) becomes larger. Figure 33 shows the current-voltage (IV) scan 3320 of a perovskite material photovoltaic device manufactured without BzAI, labeled as sample "5r", and a perovskite material photovoltaic device manufactured with BzAI, labeled as sample "10r". As can be seen from Figure 33, the perovskite material photovoltaic device manufactured with BzAI forms a current greater than n over a certain range of bias voltages than the perovskite material photovoltaic device manufactured without BzAI. Furthermore, Figure 34 shows box plots for open-circuit voltage (Voc), short-circuit current density (Jsc), packing efficiency (FF), and power conversion efficiency (PCE) for six perovskite photovoltaics fabricated without BzAI (Sample 5, r = reverse scan, f = forward scan, and s = steady-state measurement) and six perovskite photovoltaics fabricated with BzAI (Sample 10). Figure 35 shows the external quantum efficiency (EQE) for six perovskite photovoltaics fabricated without BzAI (plot 3505) and six perovskite photovoltaics fabricated with BzAI (plot 3510). Each EQE curve in Figure 35 is integrated and shown in mA / cm². 2The Jsc in units is estimated. Perovskite material devices fabricated with BzAI are shown to exhibit a higher Jsc (area under the EQE curve) than perovskite material devices fabricated without BzAI. Finally, Figure 36 shows admittance spectroscopy plot 3605 for a perovskite material photovoltaic device fabricated without BzAI, and admittance spectroscopy plot 3610 for a perovskite material photovoltaic device fabricated with BzAI. Admittance spectroscopy plot 3610 shows suppressed ion transfer in the sample device with benzylammonium compared to admittance spectroscopy plot 3605 for the sample device without benzylammonium. Excessive ion transfer is known to have detrimental effects on the properties and durability of perovskite material devices, suggesting that including benzylammonium in perovskite material photovoltaic devices may improve device properties and durability.

[0208] (Diammonium butane cation-reinforced perovskite) The introduction of 1,4-diammonium butane or other polyammonium organic compounds described below into the crystal structure of the perovskite material may improve the properties of the material. In certain embodiments, the addition of 1,4-diammonium butane to FAPbI3 perovskite as described below may provide a perovskite material with advantageous properties. In certain embodiments, 1,4-diammonium butane may be introduced into the perovskite material using a 1,4-diammonium butane salt instead of a bulky organic cation salt in the aforementioned process, and the addition of the 1,4-diammonium butane salt (or other organic polyammonium salts described in this application) may be performed at any stage of the perovskite manufacturing method in which the addition of the aforementioned bulky organic cation salt is performed. By incorporating an organic cation such as 1,4-diammonium butane into the crystal structure of the perovskite material, a general formula of the perovskite material is obtained that deviates from the "ideal" stoichiometric ratio of the perovskite material disclosed in this application. For example, due to the inclusion of such an organic cation, the perovskite material may have a stoichiometric or superstoichiometric general formula represented by the general formula FAPbI3. In this case, the general formula of the perovskite material may be represented by C x M y X z where x, y, and z are real numbers.

[0209] In certain embodiments, the 1,4-diammonium butane salt solution may be added to the lead halide precursor ink solution prior to deposition. In certain embodiments, the 1,4-diammonium butane salt may be added to the lead halide precursor ink solution at a concentration of 0.001 mol% to 50 mol%. In certain embodiments, the 1,4-diammonium butane salt may be added to the lead halide precursor ink solution at a concentration of 0.1 mol% to 20 mol%. In certain embodiments, the 1,4-diammonium butane salt may be added to the lead halide precursor ink solution at a concentration of 1 mol% to 10 mol%.

[0210] In another embodiment, as described above, 1,4-diammonium butane may be added to the formamidinium salt solution before contacting the lead halide precursor thin film. In a particular embodiment, 1,4-diammonium butane may be added to the formamidinium iodide salt solution at a concentration of 0.001 mol% to 50 mol%. In a certain embodiment, 1,4-diammonium butane may be added to the formamidinium iodide salt solution at a concentration of 0.1 mol% to 20 mol%. In a particular embodiment, 1,4-diammonium butane may be added to the formamidinium iodide salt solution at a concentration of 1 mol% to 10 mol%.

[0211] In other embodiments, the 1,4-diammonium butane precursor solution may be deposited on a lead halide thin film formed after the deposition of a lead halide precursor ink, or on a perovskite precursor thin film after the deposition of a formamidinium salt solution. In certain embodiments, the 1,4-diammonium butane precursor solution may have a concentration of 0.001 mol% to 50 mol%. In some embodiments, the 1,4-diammonium butane precursor solution may have a concentration of 0.1 mol% to 20 mol%. In certain embodiments, the 1,4-diammonium butane precursor solution may have a concentration of 1 mol% to 10 mol%.

[0212] An exemplary method for depositing a perovskite material having 1,4-diammoniumbutane comprises the steps of: depositing a lead salt precursor on a substrate to form a lead salt thin film; and depositing an organic cationic salt precursor having a first organic cationic salt on the lead salt thin film to form a perovskite precursor thin film. The lead salt precursor or organic cationic salt precursor may contain 1,4-diammoniumbutane, or the 1,4-diammoniumbutane precursor may be deposited on the lead salt thin film or perovskite precursor thin film. Finally, the substrate and the perovskite precursor thin film may be annealed to form a perovskite material having 1,4-diammoniumbutane. The lead salt precursor and the organic cationic salt precursor may have any of the solutions described herein used to form the perovskite thin film.

[0213] The length between the ammonium groups of 1,4-diammonium butane is approximately the same as the length between formamidinium cations in the crystal lattice of formamidinium lead iodide perovskite material. Therefore, 1,4-diammonium butane may substitute two formamidinium ions during the formation of the FAPbI3 material. In another embodiment, other alkyl polyammonium salts may be added to the lead halide precursor ink during the formation of the perovskite material. For example, 1,8-diammonium octane, bis(4-aminobutyl)amine, and tris(4-aminobutyl)amine may be added. Furthermore, polyammonium polycations having 1,4-diammonium butane may offer the same advantages as the bulky organic cations described above, through a mechanism similar to that described above for bulky organic cations.

[0214] Figure 13 is a schematic diagram illustrating the effect of adding 1,4-diammonium butane salt during the process of producing a perovskite material on the resulting perovskite 7000. As shown in Figure 13, the 1,4-diammonium butane cation 7020 may substitute for two formamidinium cations 7010 in the perovskite material crystal lattice. In FAPbI3 perovskite, the spacing between formamidinium cations is approximately 6.35 Å. The length of the 1,4-diammonium butane cation is approximately 6.28 Å, with a difference of only 0.07 Å. Thus, the 1,4-diammonium butane cation may substitute for the perovskite crystal lattice without significantly altering the properties or structure of the perovskite crystal lattice. In some embodiments, the addition of 1,4-diammonium butane cation to the perovskite material may enhance the properties and stability of the perovskite material. The 1,4-diammonium butane cation acts as a rigid structure within the perovskite material, increasing its structural and chemical durability. For example, in one embodiment, a perovskite material with added 1,4-diammonium butane cation may exhibit superior dry thermal stability compared to a perovskite material without added 1,4-diammonium butane cation. Furthermore, a perovskite material with added 1,4-diammonium butane cation may exhibit a blue shift in the emission spectrum of the perovskite material. In one embodiment, the 1,4-diammonium butane cation may be added to the formamidinium salt solution at a concentration of 0-20 mol%. In another embodiment, the 1,4-diammonium butane cation may be added to the formamidinium salt solution at a concentration of 1-5 mol%. In a particular embodiment, the 1,4-diammonium butane cation was added to the formamidinium salt solution at a concentration of 5 mol%.

[0215] Experimental evidence has shown that the lattice parameters do not shift significantly when 1,4-diammonium butane is added to perovskite materials up to 20%. Figure 14 shows the X-ray diffraction peaks (XRD) of perovskites with 0 mol%, 5 mol%, 10 mol%, and 20 mol% 1,4-diammonium butane ("DABI"). At each concentration, the main peak occurs at the same point, suggesting that the lattice parameters of the perovskite material do not change significantly with the addition of 1,4-diammonium butane at concentrations between 0 mol% and 20 mol%. The addition of 1,4-diammonium butane produces low-intensity diffraction at 2θ positions less than 13° in Cu-Kα radiation, which represents a small amount of 2D or layered perovskite phase.

[0216] Figure 15 shows images of perovskite samples with 0 mol%, 1 mol%, 2.5 mol%, and 5 mol% DABI, exposed to a temperature of 85°C at 0% relative humidity for 7 days. The perovskite material with 0 mol% DABI showed a noticeably brighter color after 1 day and an even more pronounced yellow after 7 days. This indicates that the perovskite material with 0 mol% DABI degraded significantly after 1 day of exposure to the test conditions. The samples of perovskite material with 1 mol%, 2.5 mol%, and 5 mol% DABI all remained dark after 7 days, suggesting that even the addition of a small amount of 1 mol% DABI significantly increases the so-called "dry heat" stability of the perovskite material.

[0217] Furthermore, the addition of 1,4-diammonium butane to the perovskite material may result in a slight blue shift in photoluminescence observed in the perovskite material compared to a perovskite material without 1,4-diammonium butane. This blue shift is obtained by the passivation of trapped states within the perovskite material caused by the addition of 1,4-diammonium butane. This blue shift indicates that the addition of 1,4-diammonium butane to the perovskite material reduces the defect density of the crystal lattice of the perovskite material without changing the crystal structure of the perovskite material. For example, compared to an FAPbI3 perovskite material without 1,4-diammonium butane, the blue shift observed in an FAPbI3 perovskite material with 20 mol% 1,4-diammonium butane added has been observed to change by 0.014 eV, from 1.538 eV in the case without 1,4-diammonium butane to 1.552 eV in the case with 20 mol% 1,4-diammonium butane.

[0218] In another embodiment, other ammonium complexes may be added during the formation of the perovskite material. For example, Figure 16 shows three ammonium compounds: 1,8-diammonium octane, bis(4-aminobutyl)-ammonium, and tris(4-aminobutyl)-ammonium. These may be added to the perovskite material in the same manner as described above with respect to the 1,4-diammonium butane cation. When introduced during the formation of the aforementioned perovskite material, 1,8-diammonium octane may occupy the spaces of two formamidinium cations ("A sites") in the crystal lattice of the FAPbI3 perovskite material. When introduced during the formation of the aforementioned perovskite material, bis(4-aminobutyl)-ammonium may occupy the spaces of three A sites in the crystal lattice of the FAPbI3 perovskite material. When introduced during the formation of the aforementioned perovskite material, tris(4-aminobutyl)-ammonium may occupy the spaces of four A sites in the crystal lattice of the FAPbI3 perovskite material. Figures 16A to 16C show stylized diagrams of the introduction of the three ammonium compounds shown in Figure 16 into the crystal lattice of the FAPbI3 perovskite material. Figure 16A is a stylized diagram of the introduction of 1,8-diammonium octane into the crystal lattice 7100 of the FAPbI3 perovskite material. As shown in Figure 16A, the 1,8-diammonium octane cation 7120 may substitute for two formamidinium cations 7110 in the crystal lattice of the perovskite material. Figure 16B is a stylized diagram of the introduction of bis(4-aminobutyl)-ammonium into the crystal lattice 7200 of the FAPbI3 perovskite material. As shown in Figure 16B, the bis(4-aminobutyl)-ammonium cation 7220 may substitute for three formamidinium cations 7210 in the crystal lattice of the perovskite material. Figure 16C is a stylized diagram of the introduction of tris(4-aminobutyl)-ammonium into the crystal lattice 7300 of the FAPbI3 perovskite material. As shown in Figure 16c, the tris(4-aminobutyl)-ammonium cation 7320 may substitute for four formamidinium cations 7310 in the crystal lattice of the perovskite material.In other embodiments, alkyldiammonium complexes having carbon chains between 2 and 20 carbon atoms may be added to the perovskite material. In some embodiments, combinations of ammonium complexes may be added to the perovskite material.

[0219] Accordingly, the present invention is suitably adapted to achieve the purposes and advantages mentioned, as well as the purposes and advantages inherent to the present invention. The particular embodiments described herein are merely illustrative, and the present invention may be modified and implemented in different equivalent ways that will be apparent to those skilled in the art who have the merits of the teachings of this application. Furthermore, except for the appended claims, the details of the configurations or designs described are not intended to be limiting. Accordingly, it is clear that the particular exemplary embodiments disclosed may be changed or modified, and all such changes will be considered within the scope and spirit of the present invention. In particular, any range of values ​​disclosed herein ("about a to about b," or equivalent "about a to b," or equivalent "about a ~ b") is understood to refer to the power set of the ranges of each value (the set of all subsets), and all ranges encompassed within the broader range of values ​​are described. Also, terms in the claims have their obvious and ordinary meanings unless otherwise explicitly defined by the patentee.

Claims

1. Perovskite material, C Ｘ M Ｙ X Ｚ A perovskite crystal lattice having the general formula, The alkylpolyammonium cation substituted within the perovskite crystal lattice, It has, In the perovskite crystal lattice, the alkylpolyammonium is substituted with at least two C cations. Here, X, Y, and Z are real numbers. C has one or more cations selected from the group consisting of Group 1 metals, Group 2 metals, ammonium, formamidinium, guanidinium, and ethenetetramine. M has one or more metals selected from the group consisting of BE, MG, CA, SR, BA, FE, CD, CO, NI, CU, AG, AU, HG, SN, GE, GA, PB, IN, TL, SB, BI, TI, Zn, CD, HG, ZR, and combinations thereof. X has one or more anions selected from the group consisting of halides, pseudohalides, chalcogenides, and combinations thereof. The alkylpolyammonium cation comprises 1,4-diammoniumbutane, 1,8-diammoniumoctane, bis(4-aminobutyl)ammonium, or tris(4-aminobutyl)ammonium, in a perovskite material.

2. The perovskite material according to claim 1, wherein the alkylpolyammonium cation has a concentration between 1 MOL% and 20 MOL% in the perovskite material.

3. The perovskite material according to claim 1, wherein the alkylpolyammonium cation has a concentration between 1 MOL% and 5 MOL% in the perovskite material.

4. The perovskite material according to claim 1, wherein the alkylpolyammonium cation is present in the perovskite material at a concentration of about 5 MOL%.

5. The perovskite material according to claim 1, wherein C has formamidinium, M has lead, and X has iodide.

6. The perovskite material according to claim 5, wherein the crystal lattice of the perovskite material has a cubic structure.

7. The perovskite material according to claim 5, wherein the ammonium group of the alkylpolyammonium cation is substituted with a formamidinium ion in the perovskite crystal lattice.

8. Formamidinium lead iodide perovskite material, The alkylpolyammonium cation substituted within the perovskite crystal lattice of the formamidinium lead iodide perovskite material, It has, In the perovskite crystal lattice, the alkylpolyammonium is substituted with at least two C cations. The alkylpolyammonium cation comprises 1,4-diammonium butane, 1,8-diammonium octane, bis(4-aminobutyl)amine, or tris(4-aminobutyl)amine, in a perovskite material.

9. The perovskite material according to claim 8, wherein the ammonium group of the alkylpolyammonium cation is substituted with a formamidinium ion in the formamidinium lead iodide perovskite material.

10. The perovskite material according to claim 8, wherein the alkylpolyammonium cation has a concentration between 1 MOL% and 20 MOL% in the perovskite material.

11. The perovskite material according to claim 8, wherein the alkylpolyammonium cation has a concentration between 1 MOL% and 5 MOL% in the perovskite material.

12. The perovskite material according to claim 8, wherein the alkylpolyammonium cation is present in the perovskite material at a concentration of about 5 MOL%.

13. The formamidinium lead iodide perovskite material has a cubic crystal structure, as described in claim 8.

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