Manufacturing of organic-inorganic composite halide films

Abstract

The present invention relates to the field of materials science, namely to a method for producing a film made of a crystalline material. The crystalline material film obtained by the method of the invention can be used, for example, in semiconductor-based optoelectronic devices, in particular solar cells. The technical result achieved by using the invention is an improvement in the homogeneity of the obtained film of organic-inorganic complex halide by reducing the number of pinholes and the surface roughness of the film, which contributes to an improvement in the overall quality of the film when used as a light absorbing material in thin-film solar cells. The technical result of the invention is achieved by an improvement in the method for producing a film of organic-inorganic complex halide with a perovskite-like structure, comprising the following steps: (I) forming a layer of reagent B or B' on a carrier substrate; II) interacting the layer of reagent B or B' with reagents AX and X2; III) effecting a reactive transformation of the applied reagents; thus, to carry out step II, the film obtained in step I is immersed in a solution of a mixture of reagents AX and X2 in an organic solvent, resulting in the reaction B' / B+AX+X2→A n BX (nz+k) +Y' [wherein B represents a metal, B' represents an oxide or salt of B, AX represents an organic or inorganic halide, X2 represents a molecular halogen, and A n BX (nz+k) represents an organic-inorganic complex halide (OICH), Y' is a reaction by-product, z=1, 2; k=2, 3, 4; n=0-4, and is kept in solution until the reactive transformation is complete to ensure proper progression of the reaction. The invention includes 19 claims, 3 tables, and 4 figures.

Description

Technical Field

[0001] The present invention relates to the field of materials science, namely, a method for manufacturing a film made of a crystalline material. The crystalline material film obtained by the method of the present invention can be used, for example, in semiconductor applications, particularly in the manufacture of solar cells.

Background Art

[0002] Organic-inorganic composite halides, particularly perovskite-like lead halides, are advanced materials used as light-absorbing materials in semiconductor devices, such as solar cells, photodetectors, LEDs, etc. Thin films of these compounds are used in the manufacture of planar semiconductor devices such as solar cells. At present, there are a wide variety of methods for obtaining the above-mentioned films in order to fabricate solar cells (so-called perovskite solar cells) based on hybrid lead halide films having a perovskite-like structure. The review article (Non-Patent Document 1) discloses the main scalable approaches for the synthesis of hybrid lead halide films for the time being. In most cases, the production of such compounds can be regarded as a binary reaction between a lead salt and an organic halide. For example, the reaction of the so-called 3D perovskite-like lead halide with the most common model compound MAPbI3 (MA = CH3NH3 ,

[0002] ) PbI2 + MAI → MAPbI3. In almost all cases, this synthetic scheme is carried out in one step (crystallization of the precursor solution applied to the substrate, simultaneous gas-phase deposition of the precursor) or two steps (each of the precursors is applied to the substrate separately using, for example, a solution or vapor-phase method, and then conditions for the completion of the chemical reaction between the compounds are created, two-step method).

[0003] [[ID=IS]]

[0004] Another precursor is a metal lead film and a reactive molten polyhalide (RPM). Their use was first described in Patent Document 1.In this case, the semiconductor material film is produced by depositing, for example, the RPM of a mixture AX-X2 onto a Pb (or Pb compound) film, where AX is an organic or inorganic halide and B2 is a halogen. This method has several advantages over classical methods, as it does not require a lead salt solution and can use a metal as the initial precursor. Metal films can be technologically advanced precursors, as there are many proven industrial approaches for their application, such as vacuum magnetron sputtering.

[0005] A drawback of known methods is that uniformly applying stoichiometric amounts of RPM to the surface of the metal (metal-containing precursor) to impart the desired functional properties to the final film is technically complex.

[0006] The problem of difficulty in uniformly applying RPM to the surface of the precursor film is partially solved by using an RPM solution instead of a pure reactive polyhalide. (Similar solutions are disclosed in Patent Documents 2 and 3). This approach is also described in Non-Patent Document 2. The above publications disclose a method based on applying an AX-X2 mixture, together with a solvent or inhibitor for its reaction with the metal-containing precursor, onto a film of the metal-containing precursor.

[0007] A potential drawback of these methods is that they essentially require the metering and administration of a liquid containing AX and X2 to a metal or metal-containing precursor, which complicates the synthesis procedure.

[0008] The methods described in Patent Documents 4 and 5, and in the papers [Non-Patent Document 3] and [Non-Patent Document 4], are the closest in technical essence to the present invention. Within the framework of the approaches described in these publications, a film of metallic lead or tin is immersed in an alcoholic solution of an organic halide (AX) and iodine (X2), thereby oxidizing the metal and forming a hybrid halide film having a perovskite-like structure. The drawback of these approaches is the selection of an isopropyl alcohol-based solvent system to carry out this experimental scheme, which leads to the formation of films with suboptimal morphology and suboptimal functional properties. As a result, the power conversion efficiency of perovskite solar cells produced by these methods does not exceed 5%.

[0009] The technical problem that the present invention aims to solve is the need to overcome the inherent shortcomings of analogs and prototypes at the expense of creating a simpler and more economical method for producing films of crystalline materials, particularly films of organic-inorganic composite halides, the method characterized by improving the functional characteristics of the manufactured material, in particular increasing the efficiency of solar cells manufactured using the method of the present invention to 13% or more. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] International Publication No. 2018124938 [Patent Document 2] Russian Patent Application Publication No. 2712151 [Patent Document 3] Russian Patent Application Publication No. 2685296 [Patent Document 4] International Publication No. 2017195191 [Patent Document 5] Chinese Patent No. 104250723 Specification [Patent Document 6] U.S. Patent No. 8963368 [Non-patent literature]

[0011] [Non-Patent Document 1] Park, Nam-Gyu, and Kai Zhu. “Scalable fabrication and coating methods for perovskite solar cells and solar modules.” Nature Reviews Materials, (US), (2020): 1-18. [Non-Patent Document 2] Belich, N. a., Petrov, aa, Rudnev, PO, Stepanov, NM, Turkevych, I., Goodilin, EA, & Tarasov, AB “From metallic lead films to perovskite solar cells through lead conversion with polyhalides solutions.” ACS Applied Materials & Interfaces, (US), (2020). [Non-Patent Document 3] Rakita, Yevgeny, et al. "Metal to halide perovskite (HaP): an alternative route to HaP coating, directly from Pb (0) or Sn (0) films." Chemistry of Materials, (US), 29.20 (17): 8620-8629 [Non-Patent Document 4] He, Yingying, et al. "Using elemental Pb surface as a precursor to fabricate large area CH3NH3PbI3 perovskite solar cells." Applied Surface Science, (Netherlands), 389 (2016): 540-546 [Non-Patent Document 5] Tutantsev, Andrei Sergeevich, Natalia N. Udalova, Sergey A. Fateev, Andrey A. Petrov, Wang Chengyuan, Eugene G. Maksimov, Eugene A. Goodilin, and Alexey B. Tarasov.” New Pigeonholing Approach for Selection of Solvents Relevant to Lead Halide Perovskites Processing.” The Journal of Physical Chemistry C, (US), (2020) [Non-Patent Document 6] Hsieh, Tsung-Yu, et al. “Crystal growth and dissolution of methylammonium lead iodide perovskite in sequential deposition: correlation between morphology evolution and photovoltaic performance.” ACS Applied Materials & Interfaces, (US), 9, 10(2017):8623-8633. [Non-Patent Document 7] Wenger, Bernard, et al. “Towards unification of perovskite stability and photovoltaic performance assessment.” arXiv preprint arXiv: 2004. 11590(2020) [Non-Patent Document 8] internet <http: / / konf.x-pdf.ru / 18fizika / 632895-l-fotovoltaicheskie-strukturi-osnove-organicheskih-poluprovodnikov-kvantovih-tochek-cdse.php> [Non-Patent Document 9] GOST R ISO 27911-2015 “National Uniform Measurement Assurance System (NMS).Chemical analysis of the surface. Scanning probe microscopy. Determining and calibrating the lateral resolution of a near-field optical microscope” (Internet<http: / / docs.cntd.ru / document / 1200119068> ) [Non-Patent Document 10] internet <https: / / www.msu.ru / science / main_themes / v-mgu-razrabotali-novuyu-strategiyu-polucheniya-perovskitnykh-solnechnykh-yacheek.html.> [Non-Patent Document 11] internet<https: / / mipt.ru / upload / medialibrary / 17b / skol_partl_pvd_dorozhkin.pdf> [Non-Patent Document 12] Mattox, Donald M. “Handbook of physical vapor deposition (PVD) processing.” William Andrew, 2010, Chapters 6, 7 [Non-Patent Document 13] Han, Sunghoon, et al. “Efficient Planar-Heterojunction Perovskite Solar Cells Fabricated by High-Throughput Sheath-Gas-Assisted Electrospray.” ACS Applied Materials & Interfaces ,(US),10, 8 (2018): 7281-7288. [Non-Patent Document 14] GOST 13.2.004-89. Reprography. Copywriting. Screen printing devices (stencil duplicators). General technical requirements, (Internet<http: / / docs.cntd.ru / document / gost-13-2-004-89> ) [Non-Patent Document 15] Yang, Chunhe, et al. “Preparation of active layers in polymer solar cells by aerosol jet printing.” ACS applied materials & interfaces,(US),3, 10 (2011): 4053-4058. [Non-Patent Document 16] Bag, Santanu, James R. Deneault, and Michael F. Durstock. “Aerosol-Jet-Assisted Thin-Film Growth of CH3NH3PbI3 Perovskites - A Means to Achieve High Quality, Defect-Free Films for Efficient Solar Cells.” Advanced Energy Materials, (US), 7, 20 (2017): 1701151 [Non-Patent Document 17] Petrov, Andrey A., and Alexey B. Tarasov. “Methylammonium polyiodides in perovskite photovoltaics: from fundamentals to applications.” Frontiers in Chemistry, (Switzerland), 8 (2020): 418. [Overview of the project] [Problems that the invention aims to solve]

[0012] The technical problem that the present invention aims to solve is the need to overcome the inherent shortcomings of analogs and prototypes at the expense of creating a simpler and more economical method for producing films of crystalline materials, particularly films of organic-inorganic composite halides, the method characterized by improving the functional properties of the manufactured material, in particular by increasing the efficiency of solar cells manufactured using the method of the present invention by 13% or more. [Means for solving the problem]

[0013] The technical achievements achieved by using this invention are an increase in the homogeneity of organic-inorganic composite halide films by reducing the number of pinholes and lowering the surface roughness of the film, which contributes to improving the efficiency of the film when used as a light-absorbing material in thin-film solar cells.

[0014] The advantages of the method of the present invention also include the simplicity of the synthesis procedure: the chemical reaction occurs when the metal-containing precursor film is immersed in the reaction solution, and there is no need to apply a measured solution to the surface of the metal-containing precursor film, thus providing high controllability and reproducibility to the synthesis procedure and increasing the size of the film produced (compared to Patent Documents 2 and 3). Solar cells based on films produced by the method of the present invention are characterized by improved efficiency (13% or more) compared to the prototype.

[0015] The technical results of the present invention are achieved by the fact that a method for producing an organic-inorganic composite halide film having a perovskite-like structure comprises the following steps: I) A step of forming a layer of reagent B or B' on a carrier substrate; II) A step of causing the layer surface of reagent B or B' to interact with reagents AX and X2; III) A step that brings about a reactive transformation of the applied reagent; therefore, in order to carry out step II, the film obtained in step I is immersed in an organic solvent solution of a mixture of reagents AX and X2, and the reaction B' / B + AX ​​+ X2 → A n BX (nz+k)+Y’ [where B represents a metal, B’ represents an oxide or salt of B, AX represents an organic or inorganic halide, X2 represents molecular halogen, and A n BX (nz+k) represents an organic-inorganic composite halide (OICH), Y’ is a reaction by-product, z = 1, 2; k = 2, 3, 4; n = 0 to 4, where n includes non-integer values]. It is held in solution until the reaction conversion is complete to ensure the proper progression of 60 、PCBM、PEIE、TaTm、NPD、CuI、CuO x 、Cu2O、PTAA、Spiro-TTB、CuGaO2 or a mixture thereof. One or a mixture of the following metals is used as reagent B: Pb, Sn, Bi, Cu, Eu, Sb, Cd, Ge, Ni, Mn, Fe, Co, Yb, Pd. Reagent B’ is a halide, chalcogenide, nitrate, or carbonate of B. The thickness of layer B or B’ is selected in the range of 10 - 1000 nm. Reagent B(B’) is applied using methods related to the compounds of the listed classifications, i.e., by vacuum, gas, or solution methods. As reagent X2, one or a mixture of the halogens I2, Br2, Cl2 is selected. The anions of the halogens (I - 、Br - 、Cl - ), SCN - or a mixture thereof is used as component X in reagent AX. Inorganic and organic cations and mixtures thereof are used as component A in reagent AX. Li + 、Na + 、K + 、Rb + 、Cs + 、NH4 + 、Cu + 、Pd + 、Pt + 、Ag+ Au + , Rh + , Ru + , or mixtures thereof, are used as inorganic cation A. Various organic substituents (R) containing functional groups such as aromatic fragments, diene groups, oxygen-containing functional groups (hydroxyl, carbonyl, carboxyl), nitrogen-containing functional groups (amino group, cyano group, etc.), sulfur-containing functional groups (thiol, sulfoxide, etc.), or monovalent substituted ammonium cations (NR) having H atoms. 1 R 2 R 3 R 4 ) + This is used as organic cation A. As the organic solvent for reagents AX and X2, a solvent belonging to the category of inert or weak solvents for organic-inorganic composite halides is used, characterized by the following parameters: (DN (number of donors) ≤ 20 kCal / mol, μ (dipole moment) ≤ 2.5 D, δ HB (Hansen parameter) ≤ 10 (MPa) 1 / 2). Chloroform, chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p-xylene, toluene, dichloromethane, benzene, diethyl ether, anisole, iodobenzene, phenethole, decane, hexane, m-xylene, dibenzyl ether, bromobenzene, mesitylene, styrene, ethylbenzene, heptane, diethyl carbonate, 1,2-dichloroethane, ethylbenzene, ethyl acetate, tetrahydrofuran, dioxane, etc., and mixtures thereof are used as organic solvents. The solvent further contains an additive of 10% by volume or less of a solvent that is not inert or weak to organic-inorganic composite halides, i.e., isopropyl alcohol, ethyl alcohol, or butyl alcohol. The concentration of AX in the solution is 0.001 mg / ml to 500 mg / ml, and the concentration of X2 in the solution is 1 to 500 mg / ml. In step II, the substrate and solution temperatures are maintained at -20°C to 200°C. In step II, the substrate is treated with a solution for a period of time ranging from 1 second to 48 hours. The film treated with the solution is then subjected to additional post-treatment, which includes washing the substrate in an organic solvent, heat treatment at a temperature of 30 to 400°C for 1 to 7200 seconds, treatment in a vacuum, inert gas environment, dry air, humid air, methylamine dimethylformamide (DMF) vapor, dimethyl sulfoxide (DMSO), halogen vapor, irradiation with visible light, UV light, or IR light, treatment with a solution solvent, or a combination of the above post-treatment methods.

[0016] A key feature of the present invention's approach is that the organic solvents for reagents AX and X2 belong to the category of solvents that are inert or weak solvents for organic-inorganic composite halides. Such solvents are characterized by the following parameters: DN (donor number) ≤ 20 kCal / mol, μ (dipole moment) ≤ 2.5 D, δ HB (Hansen parameter) ≤ 10 (MPa) 1 / 2). Here, DN (donor number) is one indicator of the basicity of the solvent, and in a 1,2-dichloroethane solution, the solvent molecules and 3-10 mol / L of Lewis acid (SbCl) 5 This is the value of -ΔH (kCal / mol) representing the heat of reaction (enthalpy) when ) reacts with ).In particular, examples of this type of solvent include chloroform, chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p-xylene, toluene, dichloromethane, benzene, diethyl ether, anisole, iodobenzene, phenethole, decane, hexane, m-xylene, dibenzyl ether, bromobenzene, mesitylene, styrene, ethylbenzene, heptane, diethyl carbonate, 1,2-dichloroethane, ethylbenzene, ethyl acetate, tetrahydrofuran, dioxane, and mixtures thereof. A more detailed description of this classification type of organic solvent is provided in publication [Non-Patent Literature 5].

[0017] The use of this solvent type avoids the degradation of the target film's morphology that can occur with alcohol solvents used in solutions that are the closest to the technical essence (Patent Documents 4 and 5). For example, isopropanol, ethanol, methanol, and butanol are δ HB Because they have a coefficient of >15, classical alcohols do not meet the selection criteria for the optimal solvent described within the scope of the present invention.

[0018] The recrystallization process of hybrid perovskite films in alcoholic solvents and the resulting degradation of morphology are described, for example, in publication [Non-Patent Literature 6]. According to the authors of this paper, in an organic iodide-containing alcoholic solvent [PbI4] 2- Partial dissolution of lead compounds, accompanied by ion generation, occurs, leading to changes in membrane morphology and the formation of pinholes within the membrane. In solvents that are inert or weak solvents for organic-inorganic composite halides, the effect of dissolution and recrystallization of such lead-containing compounds is reduced. Consequently, when hybrid perovskites are incubated in this type of solvent, membrane recrystallization accompanied by pinhole formation is not observed.

[0019] The present invention will be explained with reference to the following diagrams. [Brief explanation of the drawing]

[0020] [Figure 1]The image on the left is a micrograph of a film of the perovskite-like hybrid halide CH3NH3PbI3 (MAPbI3) produced by the method of the present invention. The diffractogram of this film is shown on the right (reflections related to MAPbI3 are marked with an asterisk). Experts will clearly recognize the relatively large crystal size within the film (supporting the improved functional properties of the film) and the absence of impurities such as unreacted components of the reaction, like metallic Pb. [Figure 2] The left graph shows the IV curve of a perovskite solar cell having an FTO / TiO2 / SnO2 / MAPbI3 / Spiro-OMeTAD / Au structure, where the MAPbI3 film is manufactured by the method of the present invention. The right graph shows the time dependence of the power conversion efficiency of a given solar cell. This is obtained by tracking the maximum power point. The resulting power conversion efficiency is substantially higher than that of the closest patents, Patent Documents 4 and 5. [Figure 3] The image on the left is a micrograph of a film of the perovskite-like hybrid halide MAxFA1-xPbIyBr3-y (MA=CH3NH3+,FA=(NH2)2CH+) produced by the method of the present invention. The diffractogram of this film is shown on the right (reflections related to MAxFA1-xPbIyBr3-y are marked with an asterisk). Experts will clearly recognize the relatively large crystal size within the film (supporting the improvement of the film's functional properties) and the absence of impurities such as unreacted components of the reaction, including metallic Pb. [Figure 4] This is a photograph of a film MAxFA1-xPbIyBr3-y with an area of ​​approximately 30 cm², produced by the method of the present invention. The visual homogeneity of the film suggests the possibility of further scaling up this synthesis method. [Modes for carrying out the invention]

[0021] Terms used The following are selected terms and definitions used in the description of this invention to best understand its essence.

[0022] Perovskite-like structures (both the perovskite structure itself and structures derived from the perovskite structural type). For the purposes of this application, the terms “perovskite-like compound” or “perovskite-like phase” refer to compounds and phases having a perovskite-like structure.

[0023] Halides having a perovskite-like structure of formula ABX3 having a cubic crystal system or any lower crystal system (e.g., tetragonal, orthorhombic), or halide perovskite compounds, and mixtures of halide perovskites of various phases. The structure of a halide perovskite is a central atom-component B (cation B) n+ ) and 6 atoms X (anion X) - The compound consists of a three-dimensional framework of vertex-connected octahedra [BX6] or distorted octahedra, comprising ABX3. In particular, it includes so-called layered perovskite phases whose formula differs from ABX3. Such compounds contain, in at least one plane, layers of vertex-connected octahedra or distorted octahedra (perovskite layers) of [BX6] composition, and this plane alternately contains other layers (e.g., Aurivillius phase, Ruddlesden-Popper phase, Dion-Jacobson phase).

[0024] Organic-inorganic composite halides (OICH) are those whose composition is A n BX (nz+k) It can be described as a monovalent or divalent organic cation A z+ (z=1, 2), polyvalent metal cation B k+ (k=2, 3, 4) and halide or pseudohalide ions X - It is a compound containing, and the ratio A / B=n is B k+ Depending on the coordination number, valency, and crystal structure motif, the values ​​can range from 0 to 4 (including non-integer values ​​for n). In certain cases, OICH may have a perovskite-like structure.

[0025] An inert or weak solvent for organic-inorganic composite halides is an organic solvent that satisfies the following parameters: DN (number of donors) ≤ 20 kCal / mol, μ (dipole moment) ≤ 2.5D δ HB (Hansen parameter) ≤ 10 (MPa) 1 / 2 .

[0026] A more detailed description of this classification type of organic solvent is given in publication [Non-Patent Document 5].

[0027] In this application, the term "solar cell stabilization efficiency" refers to the solar cell efficiency obtained by tracking the maximum power point and evaluating the power conversion efficiency value approximately 120 seconds after the start of efficiency tracking. This efficiency measurement method is disclosed, for example, in Patent Document 6 and Non-Patent Document 7.

[0028] The spin coating method used in a particular variation of the embodiment of the present invention is, for example, Paper (Non-Patent Document 8); -Non-patent document 9; -Non-patent literature 10 It is disclosed to [the relevant authority].

[0029] Vacuum sputtering techniques used in specific variations of the present invention (e.g., resistance thermal sputtering, magnetron sputtering, electron beam ("e-beam") sputtering) are, for example, -Literature (non-patent literature 11); -This book (Non-Patent Document 12) It is disclosed to [the relevant authority].

[0030] The solution application methods used in specific modifications of the present invention (inkjet printing, screen printing, substrate immersion in precursor solution (dip coating), blade coating, slot die coating, aerosol spraying, ultrasonic spraying) are, for example, - Paper (Non-Patent Document 1) It is disclosed to [the relevant authority].

[0031] In particular, the slot die coating method is a method of applying a solution to a moving substrate by pushing the solution through a slit die located near the substrate.

[0032] The electrospray method used in a specific variation of the method of the present invention is, for example, -Disclosed in the paper (Non-Patent Document 13).

[0033] The screen printing method used in a particular modification of the present invention is, for example, -Non-patent document 14 It is disclosed to [the relevant authority].

[0034] The aerosol jet printing method used in a specific modification of the present invention is, for example, - Paper (Non-Patent Document 15) - Paper (Non-Patent Document 16) It is disclosed to [the relevant authority].

[0035] Implementation of the invention In carrying out the method of the present invention, the following key steps of the process for producing a crystalline material film are highlighted.

[0036] Step I: A layer of reagent B(B') is formed on the top layer of the carrier substrate (hereinafter, B(B') refers to reagent B, or B' which is an oxide or salt of B). Step II: Immerse the film obtained in Step I in a solution of a mixture of reagents AX and X2. Step III: Remove the film from the solution and perform post-treatment. The post-treatment step is an additional step.

[0037] The present invention can be carried out using known means and methods, including those under industrial production conditions.

[0038] It has been experimentally demonstrated that the physical and chemical processes occurring in all the basic steps of the proposed process are independent of the properties of the substrate material or the top layer of the substrate, provided that the substrate material or the top layer of the substrate is selected from materials that are inert to reagents B(B'), AX, and X2, and to the solvents used in the synthesis process under experimental conditions (pressure, temperature, irradiation, etc.). For the purposes of this invention, the term "top layer" of the carrier substrate refers to the portion of the substrate to which reagent B(B') is coated in step I.

[0039] The carrier substrate may be glass, a polymer film (e.g., polyethylene terephthalate, polydimethylsiloxane, polymethyl methacrylate, polyimide, etc.), or any other optoelectronic device such as a solar cell.

[0040] In its most important practical applications, transparent conductive oxide materials (including ITO, FTO, IZO, IO:H, nickel, tin, indium, and zirconium-based and other alloy oxide materials), and other conductive materials (TiO2, SnO2, C 60 , PCBM), hole-conducting oxide materials (CuI, CuO x Materials such as Cu2O, CuGaO2, and NiO, and combinations thereof, are used as the top layer of the substrate. Potentially, materials that are sufficiently chemically inert to the reagents used in the synthesis (the most chemically active reagents in the scheme of this invention are halogens and mixtures of halogens with organic halides and organic solvents) can be used as the top layer of the substrate.

[0041] The metal can be used as reagent B. Most preferred are Pb, Sn, Bi, Cu, or mixtures thereof. Reagent B may also contain additives, and Eu, Sb, Cd, Ge, Ni, Mn, Fe, Co, Yb, Pd, or other elements may be used as additives (less than 20% by weight). The wide range of metals that can be used as reagents in the implementation of this invention is due to their similar chemical properties in interacting with numerous polyhalides (AX+X2): each of the indicated metals can be oxidized by a polyhalide to form a corresponding metal halide or composite metal halide. The reaction capacity of polyhalides is described in particular in the paper [Non-Patent Literature 17].

[0042] Reagent B' contains component B, and can be a halide, chalcogenide, nitrate, or carbonate of the above metal, as well as other salts of the above metal and mixtures thereof. Most preferably, reagents B and B' are: Pb, Sn, PbI2, SnI2, PbBr2, PbCl2, PbCO3, and mixtures thereof.

[0043] In most practical applications, reagent B films with a thickness of 10–1000 nm are used. In the best cases, a PbI2 film with a thickness of 100–500 nm or metallic Pb with a thickness of 10–200 nm is used as reagent B.

[0044] Reagent B(B') can be applied using methods related to the listed compound classifications, such as vacuum (resistive thermal evaporation, magnetron sputtering, e-beam sputtering), gas (CVD and similar methods), or solution methods (aerosol spraying including spin coating, inkjet printing, screen printing, air jet printing, dip coating, blade coating, slot die coating, electrostatic spraying, and ultrasonic spraying).

[0045] Reagent X2 can be a halogen I2, Br2, Cl2, or a mixture thereof. The most preferred is I2. - , Br - Cl - ), SCN - Alternatively, these mixtures can be used as component X of reagent AX.

[0046] Reagent AX can be a compound containing component X and cation A, and inorganic and organic cations, as well as mixtures thereof, can be used as cation A. For example, Cs + Li is most preferred for the role of inorganic cation A. + na + , K + , Rb + , and Cs + These mixtures, including the mixture itself, can be used in the role of inorganic cation A. Monovalent substituted ammonium cations (NR) having various organic substituents (R) 1 R 2 R 3 R 4 ) +In most practical variations of the method of the present invention, this can be used as organic cation A; the above organic substituents, in turn, have various functional groups such as aromatic fragments, diene groups, oxygen-containing functional groups (hydroxyl, carbonyl, carboxyl), nitrogen-containing functional groups (amino group, cyano group, etc.), sulfur-containing functional groups (thiol, sulfoxide, etc.), or represent a H atom. In most practically important implementations, the following cations are used in the role of organic cations: Cs + , Rb + , K + CH3NH3 + , (NH2)2CH + , C(NH2)3 + CH3(CH2) n NH3 + (n=1-15, including these isomers), phenylethylammonium cation, substituted phenylethylammonium cation, and mixtures thereof.

[0047] Organic solvents belonging to the category of inert or weak solvents for organic-inorganic composite halides are used as solvents for reagents A and X2. Such solvents are characterized by the following parameters: DN (donor number) ≤ 20 kCal / mol, μ (dipole moment) ≤ 2.5 D, δ HB (Hansen parameter) ≤ 10 (MPa) 1 / 2 ). In particular, examples of this type of solvent include chloroform, chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p-xylene, toluene, dichloromethane, benzene, diethyl ether, anisole, iodobenzene, phenethole, decane, hexane, m-xylene, dibenzyl ether, bromobenzene, mesitylene, styrene, ethylbenzene, heptane, diethyl carbonate, 1,2-dichloroethane, ethylbenzene, ethyl acetate, tetrahydrofuran, dioxane, and mixtures thereof. Further details regarding this classification type of organic solvent are described in publication [Non-Patent Literature 5]. In particular, this publication describes the above parameters (DN, μ, δ HBThis document describes how solvents with different values ​​of ) interact with organic-inorganic lead halides. It has been experimentally shown that so-called "inert or weak solvents for organic-inorganic complex halides" are characterized by weak solubility in lead halide components having a perovskite-like structure. For example, the use of this type of solvent is a prerequisite for the successful implementation of the present invention, as it leads to a low recrystallization rate of the perovskite film due to the mechanism described in paper [Non-Patent Literature 6].

[0048] In some embodiments of the present invention, the solvent may contain an additive (<10% by volume) of a solvent that is neither an inert nor a weak solvent for the organic-inorganic composite halide, such as an additive of isopropyl alcohol, ethyl alcohol, or butyl alcohol.

[0049] Solutions of reagents AX and X2 can be prepared by adding the required amounts of powdered AX and X2 to a suitable solvent or solvent mixture. The solvent / reagent mixture is then stored in a sealed container for the time required to reach the desired solution concentration for reagents AX and X2.

[0050] To implement the present invention, the concentration of AX in the solution can be 0.001 mg / ml to 500 mg / ml, and the concentration of X2 in the solution can be 0.1 to 500 mg / ml.

[0051] During the solution preparation process, temperature influence (temperature maintenance) within the range of -20°C to +200°C can be additionally utilized.

[0052] In the process of carrying out the present invention, the following chemical reaction scheme is performed: B+AX+X2→A n BX (nz+k) or B'+AX+X2→A n BX (nz+k) +Y', In the formula, B' / B is either B' (a substance containing component B) or pure substance B directly, and Y' is a by-product of the reaction, which occurs when an oxide or salt (B') is used as a precursor of component B. z=1, 2; k=2, 3, 4; n=0~4, and includes non-integer values ​​of n, not pure substance B.

[0053] In step II, film B(B') is treated with AX+X2 solution for 1 second to 48 hours while maintaining the temperature of the substrate and solution between -20°C and 200°C; after which the substrate is removed from the solution.

[0054] After completing the above steps, the film may be subjected to further post-treatment (Step III) by heat treatment at a temperature of 30-400°C for 1-7200 seconds, or storage in an inert gas environment, dry air, humid air, solvent vapor (e.g., DMF, DMSO, methylamine, etc.), halogen vapor, or exposure to visible light, UV light, or IR light, or solvent treatment, or a combination of the above post-treatment types.

[0055] Specific implementation examples Case 1 To form the substrate, a layer of fluorine-doped tin oxide (resistance approximately 7Ω / □) is applied to a cleaned glass substrate (substrate carrier), followed by TiO2 (approximately 20nm, spray pyrolysis) and SnO x A continuous layer (approximately 7 nm thick, chemically deposited from solution) was applied (top substrate layer). To perform step II, a 62 nm thick layer of metallic lead (reagent B) was applied on top of the top layer of the substrate using vacuum thermal resistance evaporation. The substrate temperature and quartz thickness gauge were maintained at approximately 10°C during sputtering. After evaporation, the substrate was transferred to an argon-filled glove box.

[0056] 10 mg of ammonium methyliodide (MAI) and 200 mg of I2 (reagents AX and X2) were added to 10 ml of toluene, and the mixture was then stirred in a sealed container at room temperature for 8 hours. After 8 hours, the sealed container was opened to remove the polyhalogen MAI distributed on the walls and bottom of the container. X It also contained a solution containing MAI and I2 in toluene. XSynthesis was performed by taking single-dose volumes of MAI and I2 solutions that were free of inclusions.

[0057] Next (Process II) substrate Pb / SnO x TiO2 / FTO / glass was immersed in a toluene solution of MAI+I2 in a sealed container and stored at room temperature for 20 minutes. Next, (Step III) the substrate was extracted from the solution and washed sequentially with toluene and anhydrous isopropyl alcohol. The substrate was then moved to a glove box (relative humidity <5%) and annealed at 100°C for 30 minutes.

[0058] Next, a layer of p-conductive Spiro-OMeTAD material was applied to a substrate, and electrodes (Au) were sputtered onto it. The stabilized power conversion efficiency of the perovskite solar cell obtained by tracking the maximum power point was 13%. This demonstrates the potential importance of the solution of the present invention in further practical applications.

[0059] Figure 1 shows the results of scanning electron microscopy and X-ray diffraction phase analysis of the MAPbI3 film obtained by the method of the present invention.

[0060] Figure 2 shows the IV curve and time behavior of the efficiency of a solar cell assembled using this film.

[0061] Case Study 2 100 mg of formamidinium iodide (FAI), 17 mg of methylammonium bromide (MABr), and 2 g of I2 were added to 100 ml of toluene, and the mixture was then stirred in a sealed container at room temperature for 12 hours. Next, 5 ml of the resulting solution was transferred to another container, where a Pb@SnO2@TiO2@FTO substrate was immersed. The container was heated to 50°C and stored for 35 minutes, after which the substrate was removed from the container (step III) and washed sequentially with toluene and anhydrous isopropanol.

[0062] MA obtained by the method of the present invention x FA 1-x PbI y Br 3-y Figure 3 shows the results of scanning electron microscopy and X-ray phase analysis of the film.

[0063] Composition MA x FA 1-x PbI y Br 3-y A large (6 × 5 cm) membrane was obtained using the same method. A photograph of this membrane is shown in Figure 4.

[0064] Case Study 3 Table 1 below shows the materials obtained using the synthesis method of the present invention. The table shows the selected reagents B(B'), AX, X2, their amounts, solvent, solution temperature in step 2, and processing time in step 2, respectively. The final composition of the film was determined by X-ray diffraction phase analysis (XRD). This list demonstrates the basic possibility of obtaining films of various classifications of crystalline materials, particularly transition metal halides and hybrid halides (e.g., CuI and MACu2I3), halide perovskites (so-called 3D perovskites having the general formula ABX3), and organic-inorganic composite halides (2D perovskites such as BA2MAPb2I7) using the method of the present invention.

[0065] [Table 1]

[0066] Case 4 Table 2 shows options for manufacturing materials using the method of the present invention on various substrates with different top layers.

[0067] [Table 2]

[0068] The above results demonstrate that it is potentially possible to obtain organic-inorganic composite halide films on any flat substrate that has sufficient chemical inertness to the reagents used in the synthesis process (specifically, many oxides and iodides have such inertness) using the method of the present invention.

[0069] Case Study 5 Table 3 below shows the options for obtaining materials based on the method of the present invention using different options for the post-treatment (Step III) of the halide film having a fabricated perovskite-like structure. The halide film MAPbI3 having a perovskite-like structure was obtained on a SnO x / TiO2 / FTO substrate as follows: Vacuum thermal evaporation of a metallic lead film with a thickness of about 62 nm was applied on the SnO x / TiO2 / FTO substrate, and then the substrate was immersed in a toluene solution of MAI (1 mg / ml) + I2 (20 mg / ml) and stored in this solution at room temperature for 40 minutes. Next, the obtained substrate was subjected to one of the 7 types of post-treatments shown in Table 3. For example, as part of the post-treatment No. 4, the substrate was washed with toluene and then with anhydrous isopropyl alcohol, and then dried in an argon stream and annealed at 100 °C for 30 minutes.

[0070] Then, the obtained substrate was examined by X-ray diffraction phase analysis (XRD), and a test solar cell having a structure of FTO / TiO2 / SnO x / MAPbI3 / Spiro-OMeTAD / Au was assembled from this substrate. Representative values of the power conversion efficiency of the fabricated solar cells are shown in Table 3.

[0071]

Table 3

Claims

1. A method for producing organic-inorganic composite halides having a perovskite-like structure, I) A step of forming a layer of reagent B or B' on a carrier substrate; II) The layer of reagent B or B' is made of reagents AX and X ２ A process of causing interaction with; III) A step of bringing about a reactive transformation of the applied reagent, To carry out step II, the film obtained in step I is mixed with reagents AX and X ２ Immerse in a solution consisting of a mixture of and an organic solvent. Reaction B' / B + AX ​​+ X ２ →A ｎ BX （ｎｚ＋ｋ） +Y' [In the formula, B is a metal, B' is an oxide or salt of B, AX is an organic or inorganic halide, X ２ It is a molecular halogen, A ｎ BX （ｎｚ＋ｋ） It is an organic-inorganic composite halide (OICH), Y' is a reaction byproduct, z = 1, 2; k = 2, 3, 4; n = 0 to 4, including non-integer values ​​of n. The solution is kept in place until the reactive transformation described above is completed. The aforementioned organic solvent has the following parameters: DN (number of donors) ≤ 20 kCal / mol, μ (dipole moment) ≤ 2.5D, δ ＨＢ (Hansen parameter) ≤ 10 (MPa) １／２ ) Characterized by, Inorganic and organic cations, and mixtures thereof, are used as component A in reagent AX. A method characterized in that various organic functional groups having aromatic fragments, diene groups, oxygen-containing functional groups (hydroxyl, carbonyl, carboxyl), nitrogen-containing functional groups (amino group, cyano group), or sulfur-containing functional groups (thiol, sulfoxide), or monovalent substituted ammonium cations having an H atom are used as the organic cation.

2. The layer of reagent B or B' consists of reagent B or B', AX and X ２ The method according to claim 1, wherein the film is formed on the uppermost layer of a carrier substrate made of a material that is inert to the same material.

3. The material of the uppermost layer of the substrate is a transparent conductive oxide material (ITO, FTO, IZO, InO:H, NiO, or an alloy oxide material, which is an alloy oxide material based on an oxide of a metal selected from the group consisting of nickel, tin, indium, and zirconium), or other conductive material (C ６０ , PCBM, PEIE, TaTm, NPD, CuI, CuO ｘ ,Cd ２ O, PTAA, Spiro-TTB, CuGaO ２ The method according to claim 2, which is selected from ), or a mixture thereof.

4. The method according to claim 1, wherein one of the following metals or a mixture thereof is used as reagent B: Pb, Sn, Bi, Cu, Eu, Sb, Cd, Ge, Ni, Mn, Fe, Co, Yb, Pd.

5. The method according to claim 1, wherein reagent B' is a halide, chalcogenide, nitrate, or carbonate of B.

6. The method according to claim 1, wherein the thickness of layer B or B' is selected within the range of 10 to 1000 nm.

7. The method according to claim 1, wherein reagent B (B') is applied using a method related to the listed classification of compounds, i.e., by vacuum, gas, or solution method.

8. The following halogens or mixtures thereof are used in Reagent X ２ The method according to claim 1, selected as: ２ , Br ２ , Cl ２ .

9. Halogen anions (I － , Br － , Cl － The method according to claim 1, wherein ) or a mixture thereof is used as component X in reagent AX.

10. Li ＋ Na ＋ _K ＋ , Rb ＋ , Cs ＋ NH ４ ＋ ,Cd ＋ , Pd ＋ , Pt ＋ Ag ＋ Au ＋ , Rh ＋ Ru ＋ The method according to claim 1, wherein inorganic cation A is used as a mixture thereof.

11. The method according to claim 1, wherein chloroform, chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p-xylene, toluene, dichloromethane, benzene, diethyl ether, anisole, iodobenzene, phenethole, decane, hexane, m-xylene, dibenzyl ether, bromobenzene, mesitylene, styrene, ethylbenzene, heptane, diethyl carbonate, 1,2-dichloroethane, ethylbenzene, ethyl acetate, tetrahydrofuran, dioxane, or a mixture thereof is used as the organic solvent.

12. The method according to claim 1, wherein the organic solvent contains an additive of a solvent that is not an inert solvent or weak solvent for the organic-inorganic composite halide (isopropyl alcohol, ethyl alcohol, or butyl alcohol) in an amount of 10% by volume or less.

13. The concentration of AX in the aforementioned solution is 0.001 mg / ml to 500 mg / ml, and the X in the aforementioned solution ２ The method according to claim 1, wherein the concentration is 1 to 500 mg / ml.

14. The method according to claim 1, wherein in step II, the temperature of the substrate and the solution is maintained between -20°C and 200°C.

15. The method according to claim 1, wherein in step II, the substrate is immersed in the solution for 1 second to 48 hours.

16. The method according to claim 1, wherein the film after immersion in the solution is further post-treated, the post-treatment comprising washing the substrate in an organic solvent, annealing at a temperature of 30 to 400°C for 1 to 7200 seconds, incubation in a vacuum, an inert gas environment, dry air, humid air, methylamine vapor, dimethylformamide (DMF) vapor, dimethyl sulfoxide (DMSO) vapor, halogen vapor, irradiation with visible light, UV light or IR light, treatment with a solution or solvent, or a combination of the above post-treatments.

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