Perovskite film, photoelectric device, preparation method of perovskite film and photoelectric device, and power utilization device

Abstract

The invention discloses a perovskite film, a photoelectric device, preparation methods of the perovskite film and the photoelectric device, and an electric device. The preparation method of the perovskite film comprises the following steps: coating a substrate with a solution containing BX2 or CX and DX3 to form a film layer; placing the film layer in an environment atmosphere containing HX gas and A deprotonation gas for reaction to obtain a perovskite film; wherein the perovskite chemical formula in the perovskite film comprises ABX3 or A2CDX6, A is at least one monovalent organic cation, B is at least one divalent metal cation, C is at least one monovalent metal cation, D is at least one trivalent metal cation, and X is at least one monovalent anion. According to the preparation method, the defect state density of the perovskite film can be reduced, and the grain size and uniformity in the perovskite film can be improved, so that the conversion efficiency and stability of a device can be improved when the prepared perovskite film is applied to a solar cell.

Description

Technical Field

[0001] The present application belongs to the technical field of perovskite materials, and specifically relates to a perovskite film and a photoelectric device, and a preparation method and an electrical device thereof. Background Art

[0002] Perovskite materials are a class of semiconductor nanomaterials with uniform size and high color purity. Their elemental composition has a crystal structure similar to that of the mineral CaTiO3, including single perovskite and double perovskite. Perovskite materials have strong light absorption capacity and a wide absorption range, and have great advantages in the field of optoelectronics. For example, perovskite solar cells (PSCs) with organic-inorganic hybrid perovskite materials as light-absorbing layers are developing rapidly.

[0003] There are two methods for preparing perovskite films: solution method and gas phase method. Since the cost of gas phase vacuum evaporation is too high and not suitable for large-scale production, in order to reduce costs, perovskite films are generally prepared based on the solution method. However, the film quality of perovskite films prepared by the solution method is poor. Summary of the invention

[0004] In view of the above problems, the present application provides a perovskite film and a photoelectric device and a preparation method and an electrical device thereof, aiming to solve the technical problem of how to improve the quality of perovskite film formation.

[0005] In a first aspect, an embodiment of the present application provides a method for preparing a perovskite film, comprising the following steps:

[0006] Coating a solution containing BX2 or containing CX and DX3 on a substrate to form a film layer;

[0007] The film layer is placed in an environment atmosphere containing HX gas and A deprotonated gas to react to obtain a perovskite film;

[0008] The perovskite chemical formula in the perovskite film includes ABX3 or A2CDX6, A is at least one monovalent organic cation, B is at least one divalent metal cation, C is at least one monovalent metal cation, D is at least one trivalent metal cation, and X is at least one monovalent anion.

[0009] After the solution containing BX2 or containing CX and DX3 is coated to form a film, the perovskite is generated by reacting in an ambient atmosphere containing HX gas and A deprotonated gas, and the perovskite film is prepared. In this process, there is a two-phase reaction system of the film layer solid phase and the gas phase, so that the solid phase film layer can fully convert the film-forming metal salt BX2 (or CX and DX3) into perovskite under gas phase induction to reduce the residual metal salt cation or anion content, thereby reducing the defect state density of the perovskite film; and due to gas phase induction, the metal salt BX2 gradually crystallizes to form perovskite crystals, which can improve the grain size and uniformity in the perovskite film. Therefore, the high-quality perovskite film that can be prepared by the preparation method improved in the embodiment of the present application can be used in solar cells to improve the conversion efficiency and stability of the device.

[0010] In some embodiments, the step of placing the film layer in an ambient atmosphere containing HX gas and A deprotonating gas for reaction comprises:

[0011] The substrate coated with the film layer is placed in a mixed gas containing HX gas, and then A deprotonated gas is introduced to form an ambient atmosphere for reaction.

[0012] By first placing the film layer in a mixed gas containing HX gas and then introducing A deprotonated gas, an environmental atmosphere suitable for the perovskite reaction can be easily formed, so that the metal salt BX2 (or CX and DX3) in the film layer can fully contact and react with the HX gas and A deprotonated gas in the environmental atmosphere.

[0013] In some embodiments, before introducing the deprotonating gas A, the membrane layer is first placed downward, and then the deprotonating gas A is introduced under the membrane layer.

[0014] Since deprotonated gas A is generally lighter than HX gas, after introducing the mixed gas containing HX gas, the membrane layer will be first facing downward and then deprotonated gas A will be introduced, so that the deprotonated gas A can fully contact and react with the HX gas and the membrane layer.

[0015] In some embodiments, the carrier gas in the mixed gas includes at least one of air, nitrogen, and argon.

[0016] The above-mentioned carrier gas has good stability and can provide a carrier for HX gas transmission, facilitating the controllable contact between HX gas and the membrane layer. At the same time, it serves as a carrier gas for HX gas and A deprotonation gas, providing a suitable environmental atmosphere carrier for the solid-gas reaction of perovskite, making the perovskite synthesis reliable.

[0017] In some embodiments, in the ambient atmosphere containing HX gas and A deprotonated gas, the volume fraction of HX gas in the total volume is 0.001% to 0.1%, and the volume fraction of A deprotonated gas in the total volume is 0.001% to 0.1%.

[0018] Under the ambient atmosphere conditions of the above volume fractions of HX gas and A deprotonated gas, not only is the perovskite synthesis reaction safe, but it can also fully react.

[0019] In some embodiments, the volume fraction of the HX gas in the total volume is 0.01% to 0.05%, and the volume fraction of the A deprotonated gas in the total volume is 0.01% to 0.05%.

[0020] Under the above volume fractions of HX gas and A deprotonated gas, the comprehensive effects of safety and efficiency of the perovskite synthesis reaction are better.

[0021] In some embodiments, the pressure of the ambient atmosphere is 1 to 1.25 standard atmospheres.

[0022] The gas-solid reaction of perovskite synthesis can be promoted in an ambient atmosphere of 1 to 1.25 standard atmospheric pressures, and the reaction system is safe and reliable.

[0023] In some embodiments, the temperature of the reaction in ambient atmosphere is 20-30°C.

[0024] The ambient atmosphere condition of 25 to 30°C is mild and easy to achieve, so that the gas-solid reaction of perovskite synthesis can be carried out under mild and controllable conditions.

[0025] In some embodiments, the reaction time in ambient atmosphere is 2 to 10 minutes.

[0026] The gas-solid reaction of perovskite synthesis can be fully completed within the reaction time of 2 to 10 minutes, thereby reducing the process time.

[0027] In some embodiments, after the reaction is carried out in the ambient atmosphere, an annealing treatment at 80-160° C. is further included.

[0028] After the reaction is completed, further annealing at 80-160° C. can fully volatilize the residual solvent in the film layer to form a perovskite film with better nucleation effect.

[0029] In some embodiments, the molar ratio of HX gas, A deprotonated gas and BX2 in the solution is (1-3): (1-3): 1; or,

[0030] The ratio of HX gas, A deprotonated gas and the total molar amount of CX and DX3 in the solution is (1~3):(1~3):1.

[0031] Excess HX gas and A deprotonating gas are used to react with the halide salt in the membrane layer, so that the metal salt BX2 or CX and DX3 in the membrane layer are fully converted into perovskite.

[0032] In some embodiments, the solution contains BX2, and the perovskite chemical formula in the resulting perovskite film is ABX3,

[0033] Among them, A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of, B includes Pb 2 + Sn 2+ 、Be 2+ Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ 、Zn 2+ ,Ge 2+ , Fe 2+ 、Co 2+ and Ni 2+ At least one of X includes F - , Cl - Br - and I - At least one of .

[0034] By selecting the specific types of solution BX2, HX gas and A deprotonating gas, a perovskite film of organic-inorganic hybrid perovskite material ABX3 with large grain size, good uniformity and low defect state density can be obtained.

[0035] In some embodiments, the solution contains CX and DX3, and the perovskite chemical formula in the resulting perovskite film is A2CDX6,

[0036] Among them, A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of C including Ag + and Na + At least one of D includes Bi 3+ andIn 3+ At least one of X includes F - , Cl - Br - and I - At least one of .

[0037] By selecting the specific types of CX and DX3, as well as HX gas and A deprotonation gas in the solution, a perovskite film of an organic-inorganic hybrid perovskite material A2CDX6 with large grain size, good uniformity and low defect state density can be obtained.

[0038] In some embodiments, the HX gas is selected from at least one of HF, HCl, HBr and HI; and / or

[0039] A deprotonating gas is selected from at least one of CH3NH2, CH3CH2NH2, CH3CH2CH2NH2 and CH2(NH2)2.

[0040] The HX gas and the A deprotonated gas react with the film layer to form X sites and A sites in the perovskite accordingly.

[0041] In a second aspect, an embodiment of the present application provides a perovskite film, and the perovskite film is prepared by the preparation method of the embodiment of the present application.

[0042] The perovskite film is prepared by utilizing the unique preparation method of the embodiment of the present application. The perovskite film has a large grain size, good uniformity, and low defect state density, and therefore has good photoelectric conversion efficiency and stability.

[0043] In some embodiments, the average grain size of the perovskite grains in the perovskite film is 700-900 nm.

[0044] The above-mentioned perovskite film with large grain size has better photoelectric conversion efficiency and stability.

[0045] In a third aspect, an embodiment of the present application provides a photoelectric device, which includes the perovskite film of an embodiment of the present application.

[0046] Because the optoelectronic device of the embodiment of the present application includes a unique perovskite film, such a perovskite film has a large grain size, good uniformity, and low defect state density, so that the optoelectronic device using the perovskite film has good photoelectric conversion efficiency and stability.

[0047] In some embodiments, the optoelectronic device comprises a solar cell.

[0048] The solar cell uses the perovskite film unique to the embodiment of the present application, which can better convert light energy into electrical energy, so that the solar cell has good photoelectric conversion efficiency and stability.

[0049] In some embodiments, the optoelectronic device includes a stacked first electrode, a hole transport layer, a perovskite layer, an electron transport layer, and a second electrode; wherein the perovskite layer contains a perovskite film of an embodiment of the present application.

[0050] The optoelectronic device with this structure is beneficial to the transport of holes and electrons in the device, and can improve the carrier transport performance of the device, thereby further improving the photoelectric conversion efficiency.

[0051] In a fourth aspect, an embodiment of the present application provides a method for preparing an optoelectronic device, comprising:

[0052] The perovskite layer is prepared, and the steps of preparing the perovskite layer include: preparing a perovskite film using the preparation method of the embodiment of the present application.

[0053] By preparing a perovskite film using the perovskite film preparation method provided in the first aspect of the embodiment of the present application when preparing the perovskite layer of the optoelectronic device, the perovskite layer prepared in this way has a large grain size, good uniformity, and low defect state density, so that the prepared optoelectronic device has good photoelectric conversion efficiency and stability.

[0054] In a fifth aspect, an embodiment of the present application provides an electrical device, which includes the optoelectronic device of an embodiment of the present application.

[0055] By adopting the optoelectronic device provided in the third aspect of the embodiment of the present application, such an electrical device has high photoelectric conversion efficiency and good stability, and can work better.

[0056] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0058] Figure 1 It is a schematic diagram of the process of preparing the perovskite film according to an embodiment of the present application;

[0059] Figure 2 is a schematic structural diagram of a solar cell according to an embodiment of the present application;

[0060] Figure 3 This is a SEM image of the perovskite film obtained in Example 1 of the present application;

[0061] Figure 4 This is a SEM image of the perovskite film obtained in Example 2 of the present application;

[0062] Figure 5This is a SEM image of the perovskite film obtained in Example 3 of the present application;

[0063] Figure 6 This is a SEM image of the perovskite film obtained in Example 4 of the present application;

[0064] Figure 7 is a SEM image of the perovskite film obtained in Example 5 of the present application;

[0065] Figure 8 This is a SEM image of the perovskite film obtained in Comparative Example 1 of the present application;

[0066] Fig. 9 This is a SEM image of the perovskite film obtained in Comparative Example 2 of the present application.

[0067] Description of reference numerals:

[0068] 1-first electrode, 2-hole transport layer, 3-perovskite layer, 4-electron transport layer, 5-second electrode. DETAILED DESCRIPTION

[0069] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0070] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0071] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0072] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0073] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0074] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces). "At least one" refers to more than one (including one, two, three, etc.).

[0075] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0076] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0077] As traditional energy resources are increasingly scarce, the development of new energy sources has received increasing attention. Due to the new demand for green energy in modern society, solar cells that convert light energy into electrical energy through the photoelectric effect have developed rapidly. At present, solar cells have developed to the third generation, namely perovskite solar cells (PSCs). Perovskite solar cells have the advantages of high photoelectric conversion efficiency and low power generation cost, and have the potential to be integrated with buildings. They are expected to become a substitute for curtain wall decoration of high-rise buildings, thereby achieving lighting and power generation at the same time.

[0078] Perovskite solar cells are solar cells that use perovskite-type organic metal halide semiconductors as light-absorbing materials. Perovskite, as a synthetic material, has become popular since it was applied to the field of photovoltaic power generation due to its excellent performance, low cost and huge commercial value. The quality of the perovskite film layer, as the light-absorbing layer in perovskite solar cells, directly affects the conversion efficiency and stability of the device.

[0079] The existing perovskite film forming methods include solution method and gas phase method. The solution method includes one-step solution method and two-step solution method, and the gas phase method includes vacuum evaporation method and dual-source gas phase evaporation method. The gas phase deposition method is too expensive and not suitable for large-scale production. Therefore, in order to reduce costs, perovskite films are generally prepared based on the solution method. However, the quality of perovskite films prepared by the solution method is difficult to control, and the uniformity needs to be improved. Therefore, the perovskite film layer formed by the solution film affects the device performance.

[0080] Based on the above considerations, in order to overcome the defect of poor film quality of the current perovskite film solution, the present application embodiment designs a method for preparing a perovskite film by synthesizing perovskite with the aid of gas. After the halide solution is coated to form a film, the perovskite is generated by reacting in an ambient atmosphere containing HX gas and A deprotonated gas. Such a perovskite film has a large grain size, good uniformity, and low defect state density, and can be well used in optoelectronic devices. Therefore, the following technical solution is proposed.

[0081] Preparation method of perovskite film

[0082] In the first aspect, the present invention provides a method for preparing a perovskite film. Figure 1 The method for preparing the perovskite film of the embodiment of the present application comprises the following steps:

[0083] S01: coating a solution containing BX2 or containing CX and DX3 on a substrate to form a film layer;

[0084] S02: placing the film layer in an environment atmosphere containing HX gas and A deprotonated gas to react and obtain a perovskite film;

[0085] The perovskite chemical formula in the perovskite film includes ABX3 or A2CDX6, A is at least one monovalent organic cation, B is at least one divalent metal cation, C is at least one monovalent metal cation, D is at least one trivalent metal cation, and X is at least one monovalent anion.

[0086] The metal salt BX2 in the solution corresponds to BX2 formed by divalent metal cation B and monovalent anion X in the single perovskite ABX3, and the metal salts CX and DX3 in the solution correspond to CX and DX3 formed by monovalent metal cation C and trivalent metal cation D in the double perovskite A2CDX6 and monovalent anion X, respectively. The solution containing BX2 or containing CX and DX3 can be prepared by dissolving the above metal salts in a solvent. The above solution is coated on a substrate to form a film layer containing metal salt BX2 or containing CX and DX3, so that it can react with subsequent HX gas and A deprotonated gas to synthesize perovskite by gas-solid reaction.

[0087] HX gas is a gas formed by the combination of monovalent anion X in the perovskite ABX3 or A2CDX6 with hydrogen, and A deprotonated gas is a gas formed after the deprotonation of monovalent organic cation A in the perovskite ABX3 or A2CDX6. The ambient atmosphere containing HX gas and A deprotonated gas can be understood as the ambient atmosphere of the gas-solid reaction system provided when the film layer containing BX2 or containing CX and DX3 formed in the above steps is subjected to the perovskite synthesis reaction with HX gas and A deprotonated gas. The gas-solid reaction referred to in the embodiment of the present application refers to the simultaneous existence of a solid phase and a gas phase in the reaction system. For example, in the embodiment of the present application, the film layer is placed in an ambient atmosphere containing HX gas and A deprotonated gas for reaction, so that the solid phase film layer and the gas phase HX gas and A deprotonated gas undergo a perovskite synthesis reaction.

[0088] The preparation method of the perovskite film provided in the embodiment of the present application, after the solution is coated to form a film, the perovskite is generated by reacting in an ambient atmosphere containing HX gas and A deprotonated gas, because there is a two-phase reaction system of the film layer solid phase and gas phase in the process, so that the solid phase film layer can fully convert the film-forming metal salt BX2 (or CX and DX3) into perovskite under gas phase induction, so as to reduce the residual metal salt cation or anion content, thereby reducing the defect state density of the perovskite film; and due to gas phase induction, the metal salt BX2 gradually crystallizes to form perovskite crystals, which can improve the grain size and uniformity in the perovskite film. Therefore, the high-quality perovskite film that can be prepared by the preparation method improved in the embodiment of the present application, and the perovskite film obtained in this way can be used in solar cells to improve the conversion efficiency and stability of the device.

[0089] In some embodiments, if the prepared perovskite film is a single perovskite ABX3, the reaction raw materials are BX2, HX gas and A deprotonation gas; if the prepared perovskite film is a double perovskite A2CDX6, the reaction raw materials are CX and DX3, HX gas and A deprotonation gas. Both perovskite films can be achieved.

[0090] Step S01 is a solution film forming step.

[0091] The solution containing BX2 or containing CX and DX3 can be prepared by dissolving the corresponding metal salt in a solvent, wherein the solvent can be water, or at least one of dimethyl sulfoxide (DMSO), γ-butyrolactone (GBL), 1-methyl-2-pyrrolidone (NMP) and N,N-dimethylformamide (DMF). In the solution containing CX and DX3, CX and DX3 can be prepared in an equal molar ratio. The above solution is coated on a substrate to form a film layer containing BX2 or containing CX and DX3.

[0092] In some embodiments, the concentration of the metal salt in the solution containing BX2 or containing CX and DX3 can be 1 to 2 M (mol / L), specifically, BX2 can be dissolved in a solvent to prepare a 1 to 2 M solution containing BX2, or equimolar amounts of CX and DX3 can be dissolved in a solvent to prepare a 1 to 2 M solution containing CX and DX3. The metal salt is uniformly dispersed within the above concentration range.

[0093] In one embodiment, the solution can be coated on the substrate by spin coating, wherein the spin coating speed can be 1000-5000 rpm / s. After spin coating, heat treatment is performed at 60-100° C. to obtain a film layer containing BX2 or containing CX and DX3.

[0094] In some embodiments, the solution contains BX2, and the perovskite chemical formula in the obtained perovskite film is ABX3, wherein A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of, B includes Pb 2+ Sn 2+ 、Be 2+ Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ 、Zn 2+ ,Ge 2+ , Fe 2+ 、Co 2+ and Ni 2+ At least one of X is a halogen anion including F - , Cl - Br - and I - At least one of .

[0095] By selecting the specific types of halide salt BX2 in the solution and HX gas and A deprotonated gas in the ambient atmosphere, a perovskite film of organic-inorganic hybrid perovskite material ABX3 with large grain size, good uniformity and low defect state density can be obtained.

[0096] In some embodiments, the solution contains CX and DX3, and the perovskite chemical formula in the obtained perovskite film is A2CDX6, wherein A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of C including Ag + and Na + At least one of D includes Bi 3+ andIn 3+ At least one of X is a halogen anion including F - , Cl - Br - and I - At least one of .

[0097] By selecting the specific types of halide salts CX and DX3 in the solution and HX gas and A deprotonated gas in the ambient atmosphere, a perovskite film of organic-inorganic hybrid perovskite material A2CDX6 with large grain size, good uniformity and low defect state density can be obtained.

[0098] Step S02 is a step of generating a perovskite film by gas-solid reaction.

[0099] In some embodiments, the step of placing the film layer in an ambient atmosphere containing HX gas and A deprotonated gas for reaction includes: placing the substrate coated with the film layer in a mixed gas containing HX gas, and then introducing A deprotonated gas to form an ambient atmosphere for reaction.

[0100] Specifically, the mixed gas containing HX gas is a mixed gas formed by HX gas and carrier gas. By first placing the film layer in the mixed gas containing HX gas and then introducing A deprotonated gas, an environment atmosphere suitable for perovskite reaction can be easily formed, so that the metal salt BX2 (or CX and DX3) of the film layer is fully contacted and reacted with the HX gas and A deprotonated gas in the environment atmosphere.

[0101] In one embodiment, the above reaction process can be carried out in a sealed container that can pass gas. Specifically, the substrate coated with the film layer is placed in a sealed container that can pass gas, and a mixed gas containing HX gas is first introduced into the sealed container, and then A deprotonated gas is introduced to form an ambient atmosphere, and the ambient atmosphere is maintained for reaction. The sealed container that can pass gas provides a gas-solid reaction space for perovskite synthesis. The embodiment of the present application can directly introduce an ambient atmosphere containing HX gas and A deprotonated gas into the sealed container, but in order to better control the reaction system, a mixed gas containing HX gas can be introduced into the sealed container first, and then A deprotonated gas can be introduced, so that an ambient atmosphere suitable for perovskite synthesis can be formed conveniently and controllably, so that the metal salt BX2 (or CX and DX3) of the film layer is fully contacted and reacted with the HX gas and A deprotonated gas in the ambient atmosphere.

[0102] In some embodiments, the substrate coated with the film layer is placed in a mixed gas containing HX gas, and then the film layer is facing downward, and A deprotonated gas is introduced below the film layer to form an ambient atmosphere, and the ambient atmosphere is maintained for reaction. That is, before introducing A deprotonated gas, the film layer is first facing downward, and then A deprotonated gas is introduced below the film layer. Because A deprotonated gas is generally lighter than HX gas, after introducing the mixed gas containing HX gas, the film layer can be first facing downward and then A deprotonated gas can be introduced, so that A deprotonated gas can fully contact and react with HX gas and the film layer.

[0103] In some embodiments, the above reaction process can be carried out in a sealed container that can pass gas. Specifically, the substrate coated with the film layer is placed in a sealed container that can pass gas, and a mixed gas containing HX gas is first introduced into the sealed container, and then the sealed container is inverted and then A deprotonated gas is introduced to form an ambient atmosphere, and the ambient atmosphere is maintained for reaction. Because A deprotonated gas is generally lighter than HX gas, after the mixed gas containing HX gas is introduced, the sealed container is inverted and then A deprotonated gas is introduced, so that A deprotonated gas can fully contact and react with HX gas and the film layer, so that the raw materials for perovskite synthesis can fully contact and react.

[0104] In some embodiments, the carrier gas in the mixed gas containing HX gas includes at least one of air, nitrogen and argon. The mixed gas containing HX gas is a mixed gas that uses the carrier gas as a carrier to assist the transmission of HX gas.

[0105] The above-mentioned carrier gas has good stability and can provide a carrier for HX gas transmission, so that HX gas can be controlled to be input into a closed container. At the same time, it can be used as a carrier gas for HX gas and A deprotonation gas, and provide a carrier for the solid-gas reaction of perovskite, so that the synthesis of perovskite is reliable. In this way, the carrier gas of the mixed gas containing HX gas is the same as the carrier gas of the ambient atmosphere containing HX gas and A deprotonation gas.

[0106] Specifically, the carrier gas may be at least one of dry air, nitrogen and argon.

[0107] In some embodiments, after the A deprotonating gas is introduced, a carrier gas is also introduced to form an ambient atmosphere. Specifically, the substrate coated with the film layer is placed in a sealed container that can pass gas, and a mixed gas containing HX gas is first introduced into the sealed container, and then the A deprotonating gas is introduced, and then the carrier gas is further introduced to form an ambient atmosphere, thereby maintaining the ambient atmosphere for reaction. After the mixed gas containing HX gas and the A deprotonating gas are introduced in sequence, the carrier gas is finally introduced, so that the ambient atmosphere with the required air pressure can be controllably and adjustably formed.

[0108] In some embodiments, in the ambient atmosphere containing HX gas and A deprotonated gas, the volume fraction of HX gas in the total volume is 0.001% to 0.1%, and the volume fraction of A deprotonated gas in the total volume is 0.001% to 0.1%. In the exemplary embodiment, the volume fraction of HX gas can be 0.001%, 0.005%, 0.01%, 0.015%, 0.018%, 0.02%, 0.025%, 0.028%, 0.03%, 0.035%, 0.038%, 0.04%, 0.045%, 0.05%, 0.06%, 0.065%, 0.07%, 0.075%, 0.08%, 0.085%, 0.09%, 0.1%, etc. The volume fraction of the deprotonated gas A can be 0.001%, 0.005%, 0.01%, 0.015%, 0.018%, 0.02%, 0.025%, 0.028%, 0.03%, 0.035%, 0.038%, 0.04%, 0.045%, 0.05%, 0.06%, 0.065%, 0.07%, 0.075%, 0.08%, 0.085%, 0.09%, 0.1%, etc. Under the above volume fraction HX gas and A deprotonated gas ambient atmosphere conditions, not only is the perovskite synthesis reaction safe, but it can also fully react.

[0109] In some embodiments, the volume fraction of HX gas in the total volume is 0.01% to 0.05%, and the volume fraction of A deprotonated gas in the total volume is 0.01% to 0.05%. Under the above volume fractions of HX gas and A deprotonated gas, the safety and efficiency of the perovskite synthesis reaction are better.

[0110] In some embodiments, the pressure of the ambient atmosphere containing the HX gas and the A deprotonating gas is 1 to 1.25 standard atmospheres.

[0111] Standard atmospheric pressure (atmosphere, atm) refers to the air pressure of 1 atm under standard conditions. The standard state of the embodiment of the present application may refer to a standard state measured at a temperature of 293.15K (20°C) and a pressure of 101.325KPa. In the exemplary embodiment, the pressure of the ambient atmosphere containing HX gas and A deprotonated gas may be 1 standard atmosphere, 1.1 standard atmospheres, 1.15 standard atmospheres, 1.2 standard atmospheres, 1.25 standard atmospheres, and other typical but non-restrictive pressures. In an ambient atmosphere of 1 to 1.25 standard atmospheres, the gas-solid reaction of perovskite synthesis can be promoted, and the reaction system is safe and reliable.

[0112] In some embodiments, the temperature of the reaction in the ambient atmosphere containing HX gas and A deprotonating gas is 20-30° C. In an exemplary embodiment, the temperature may be 20° C., 25° C., 26° C., 28° C., 30° C., etc., which are typical but non-limiting temperatures.

[0113] Specifically, the film layer is placed in the above-mentioned ambient atmosphere containing HX gas and A deprotonated gas, and the ambient atmosphere is maintained at 20-30° C. for perovskite synthesis. The ambient atmosphere under this temperature condition is mild and easy to achieve, so that the gas-solid reaction of perovskite synthesis can be carried out in a mild and controllable manner.

[0114] In some embodiments, the reaction time in the ambient atmosphere containing HX gas and A deprotonating gas is 2 to 10 minutes. In exemplary embodiments, the above time can be 2 minutes, 3 minutes, 5 minutes, 8 minutes, 10 minutes, etc., which are typical but not limiting.

[0115] Specifically, the film layer is placed in the above-mentioned environment atmosphere containing HX gas and A deprotonated gas to react for 2 to 10 minutes, so that the gas-solid reaction of perovskite synthesis can be fully completed, thereby reducing the process time.

[0116] In some embodiments, after the reaction is carried out in the ambient atmosphere, an annealing treatment at 80-160° C. is further included. Specifically, after the film layer is placed in the ambient atmosphere containing the HX gas and the A deprotonating gas for reaction, an annealing treatment at 80-160° C. is performed. In the exemplary embodiment, the annealing temperature can be 80° C., 85° C., 88° C., 90° C., 92° C., 95° C., 98° C., 100° C., 105° C., 110° C., 120° C., 130° C., 140° C., 150° C., 160° C., and other typical but non-limiting temperatures.

[0117] After the perovskite synthesis reaction is completed, further annealing at 80-160° C. can fully volatilize the residual solvent in the film layer to form a perovskite film with better nucleation effect. Furthermore, the annealing time can be 2-10 minutes.

[0118] In some embodiments, the molar ratio of HX gas, A deprotonated gas and halide salt in the halide salt solution is (1-3): (1-3): 1. In exemplary embodiments, the molar ratio of HX gas and A deprotonated gas to halide salt (BX2, or the total amount of CX and DX3) can be 1:1:1, 1.5:1.5:1, 1.7:1.7:1, 2:2:1, 2.5:2.5:1, 2.8:2.8:1, 3:3:1, etc.

[0119] By using excess HX gas and A deprotonated gas to react with the metal salt in the film layer, not only can the required gas pressure of the ambient atmosphere for the perovskite reaction be formed, but also the metal salt BX2 (or CX and DX3) in the film layer be fully converted into perovskite.

[0120] Furthermore, the molar ratio of HX gas and A deprotonated gas to the halide salt in the halide salt solution can be (1-2): (1-2): 1. Under the same other conditions, the perovskite generated by this molar ratio has fewer surface defects and is more stable.

[0121] In some embodiments, the HX gas is selected from at least one of HF, HCl, HBr and HI; the A deprotonating gas is selected from at least one of CH3NH2, CH3CH2NH2, CH3CH2CH2NH2 and CH2(NH2)2. The HX gas and the A deprotonating gas react with the film layer to form the X-site element and the A-site element in the perovskite.

[0122] Perovskite film

[0123] In a second aspect, the embodiment of the present application provides a perovskite film, which is prepared by the preparation method of the embodiment of the present application. Specifically, the perovskite film of the embodiment of the present application is obtained by coating a solution containing BX2 or containing CX and DX3 on a substrate to form a film layer, and then placing it in an ambient atmosphere containing HX gas and A deprotonated gas for reaction.

[0124] The embodiment of the present application prepares a perovskite film by utilizing a preparation method unique to the embodiment of the present application. Such a perovskite film has a large grain size, good uniformity, and low defect state density, and therefore has excellent photoelectric conversion efficiency and stability.

[0125] In some embodiments, the perovskite chemical formula in the perovskite film of the embodiment of the present application is ABX3, and the perovskite film is prepared by the preparation method of the embodiment of the present application; wherein A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of B including Pb 2+ Sn2+ 、Be 2+ Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ 、Zn 2+ ,Ge 2+ , Fe 2+ 、Co 2+ and Ni 2+ At least one of X includes F - , Cl - Br - and I - At least one of the following. The embodiments of the present application provide a perovskite film of an organic-inorganic hybrid perovskite material ABX3 with large grain size, good uniformity, and low defect state density.

[0126] In some embodiments, the perovskite chemical formula in the perovskite film of the embodiment of the present application is A2CDX6, and the perovskite film is prepared by the preparation method of the embodiment of the present application; wherein A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of C including Ag + and Na + At least one of D includes Bi 3+ andIn 3+ At least one of X includes F - , Cl - Br - and I - At least one of the following. The embodiments of the present application provide a perovskite film of an organic-inorganic hybrid perovskite material A2CDX6 with large grain size, good uniformity, and low defect state density.

[0127] Specifically, the perovskite material in the perovskite film includes but is not limited to at least one of CH3NH3PbI3 (abbreviated as MAPbI3) and CH(NH2)2PbI3 (abbreviated as FAPbI3). The band gap of the perovskite film can be 1.20 to 2.30 eV, and the band gap measurement method is to test the perovskite film through ultraviolet absorption spectrum, obtain the ultraviolet absorption curve, and then calculate the perovskite band gap through the Tauc equation.

[0128] Specifically, the thickness of the perovskite film is between 400 and 1000 nm, such as 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, and 1000 nm. The perovskite film within this thickness range has a uniform size and reduced surface grain boundaries, which can greatly improve the performance of optoelectronic devices.

[0129] In some embodiments, the average grain size of the perovskite grains in the perovskite film is 700-900 nm.

[0130] The average particle size represents a scale of the geometric size of a solid particle group. In this application, the average particle size is represented by D50, which is the particle size corresponding to when the cumulative particle size distribution percentage of a sample reaches 50%. In the embodiment of this application, the average particle size D50 of the perovskite grains in the perovskite film can be 700nm, 750nm, 800nm, 850nm, 900nm, etc. The average particle size D50 of the perovskite grains in the perovskite film is 700-900nm, which has better photoelectric conversion efficiency and stability.

[0131] Furthermore, the main size of the perovskite grains in the perovskite film of the present application is 800-1000 nm, and the average grain size D50 is 700-900 nm. The perovskite film with a large grain size has better photoelectric conversion efficiency and stability.

[0132] Optoelectronic devices

[0133] In a third aspect, an embodiment of the present application provides a photoelectric device, which includes the perovskite film of an embodiment of the present application.

[0134] Because the optoelectronic device of the embodiment of the present application includes a unique perovskite film, that is, the perovskite film prepared by the preparation method of the embodiment of the present application, such a perovskite film has a large grain size, good uniformity, and low defect state density, so that the optoelectronic device using the perovskite film has good photoelectric conversion efficiency and stability.

[0135] In some embodiments, the optoelectronic device includes a solar cell. The solar cell uses a perovskite film unique to the embodiments of the present application, which can better convert light energy into electrical energy, so that the solar cell has good photoelectric conversion efficiency and stability.

[0136] In some embodiments, Figure 2 As shown, the optoelectronic device includes a stacked first electrode 1, a hole transport layer 2, a perovskite layer 3, an electron transport layer 4, and a second electrode 5; wherein the perovskite layer 3 contains a perovskite film of the embodiment of the present application, the perovskite film has a large grain size, good uniformity, and a low defect state density. Specifically, the perovskite material chemical formula in the perovskite layer 3 satisfies ABX3 or A2CDX6, and is prepared by a unique preparation method of the embodiment of the present application. The optoelectronic device of this structure is conducive to the transmission of holes and electrons in the device, and can improve the carrier transport performance of the device, thereby further improving the photoelectric conversion efficiency.

[0137] In some embodiments, the first electrode 1 can be a transparent conductive substrate, including but not limited to the following materials: fluorine-doped tin oxide (FTO), indium-doped tin oxide (ITO), aluminum-doped zinc oxide (AZO), boron-doped zinc oxide (BZO), indium-doped zinc oxide (IZO), etc.

[0138] In some embodiments, the hole transport layer 2 can be at least one of the following materials and their derivatives and materials obtained by doping or passivation: poly [bis (4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA), poly-3-hexylthiophene (P3HT), triphenylamine with triptycene as the core (H101), 3,4-ethylenedioxythiophene-methoxytriphenylamine (EDOT-OMeTPA), N- (4-aniline) carbazole-spirobifluorene (CzPAF-SBF), poly (3,4-ethylenedioxythiophene): poly (styrene sulfone) (PEDOT:PSS), polythiophene, nickel oxide (NiO x ), molybdenum oxide (MoO3), cuprous iodide (CuI), cuprous oxide (CuO), etc.

[0139] In some embodiments, the electron transport layer 4 can be at least one of the following materials and their derivatives and materials obtained by doping or passivation: [6,6]-phenyl C61 butyric acid methyl ester (PC61BM), [6,6]-phenyl C71 butyric acid methyl ester (PC71BM), fullerene C60 (C60), fullerene C70 (C70), tin dioxide (SnO2), zinc oxide (ZnO), etc.

[0140] In some embodiments, the second electrode 5 may be a metal electrode, or may be one or more of a conductive oxide electrode.

[0141] Method for preparing optoelectronic device

[0142] In a fourth aspect, an embodiment of the present application provides a method for preparing an optoelectronic device, comprising:

[0143] The perovskite layer is prepared, and the steps of preparing the perovskite layer include: preparing a perovskite film using the preparation method of the embodiment of the present application.

[0144] The method for preparing the optoelectronic device of the embodiment of the present application adopts the method for preparing the perovskite film provided in the embodiment of the present application to prepare the perovskite film when preparing the perovskite layer of the optoelectronic device. Therefore, the perovskite layer prepared in this way has a large grain size, good uniformity, and low defect state density, so that the prepared optoelectronic device has good photoelectric conversion efficiency and stability.

[0145] Taking the photoelectric device as a perovskite solar cell as an example, the preparation method includes: providing a first electrode 1, preparing a hole transport layer 2 on the first electrode 1, preparing a perovskite layer 3 on the hole transport layer 2 (specifically, the perovskite film is prepared by the preparation method of the embodiment of the present application), preparing an electron transport layer 4 on the perovskite layer 3, and preparing a second electrode 5 on the electron transport layer 4. The specific steps are as follows:

[0146] Step 1: Etch and clean the first electrode 1 (such as a transparent conductive glass substrate), blow dry and set aside;

[0147] Step 2: Prepare a hole transport layer 2 on the first electrode 1 for later use;

[0148] Step 3: preparing a perovskite layer 3 on the hole transport layer 2. The perovskite layer 3 is prepared by solid-gas reaction. Specifically, a halide solution containing BX2 or CX and DX3 is coated on the substrate of the hole transport layer 2 to form a film layer, and then placed in an environment containing HX gas and A deprotonated gas for reaction;

[0149] Step 4: preparing an electron transport layer 4 on the perovskite layer 3 for standby use;

[0150] Step 5: Prepare a second electrode 5 on the electron transport layer 4 and test its efficiency and stability.

[0151] The specific material types of the first electrode 1 , the hole transport layer 2 , the perovskite layer 3 , the electron transport layer 4 , and the second electrode 5 have been described in detail above.

[0152] Electrical devices

[0153] In a fifth aspect, the present application also provides an electrical device, which includes the optoelectronic device of the above-mentioned application. The optoelectronic device can be used as a photoelectric conversion device of the electrical device to convert light energy into electrical energy. Therefore, the electrical device of the present application has high photoelectric conversion efficiency and good stability.

[0154] The electrical device of the embodiment of the present application can be, but is not limited to, household lighting and power supply. For example, when the photovoltaic device used is a solar cell, the electrical device can be installed on a roof or a courtyard to convert solar energy into electrical energy to provide lighting and power supply for the household. As another example, the electrical device can be a solar power station. For example, solar cells can be used to build a solar power station to convert solar energy into electrical energy and transmit it to the power grid to provide clean energy for the city.

[0155] Example

[0156] Hereinafter, the embodiments of the present application will be described. The embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If no specific techniques or conditions are indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be obtained commercially.

[0157] Example 1

[0158] A solar cell includes a stacked ITO substrate, a hole transport layer, a perovskite layer, an electron transport layer and a copper electrode. The preparation steps are as follows:

[0159] Step 1: Take 20 pieces of ITO conductive glass with a specification of 2.0*2.0cm, remove 0.35cm of ITO at both ends by laser etching, and expose the glass substrate; ultrasonically clean the etched ITO conductive glass several times with water, acetone, and isopropanol in turn; blow the ITO conductive glass dry with a nitrogen gun, and put it into a UV ozone machine for further cleaning to obtain an ITO substrate treated with UV ozone;

[0160] Step 2: Spin-coat 2 mg / mL of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) at a rate of 5000 rpm / s on the UV-ozone treated ITO substrate, and anneal on a hot plate at 100° C. for 10 minutes to obtain a hole transport layer.

[0161] Step 3: Spin-coat 50uL of 1.4M lead iodide DMF solution on the hole transport layer at 3000rpm / s, treat at 100℃ for 1min to form a film layer containing lead iodide, and then place it in a sealed container that can pass gas, with the film layer facing up and fixed at the bottom of the sealed container, and let dry air + hydrogen iodide pass. After the pressure rises to 1 standard atmosphere, turn the container upside down, and then pass methylamine gas, and then add dry air to raise the total gas pressure to about 1.25 standard atmospheres to form an ambient atmosphere (including 0.07mol hydrogen iodide gas and 0.07mol methylamine gas). The ambient atmosphere is maintained at 20℃ for 5min, and the reaction can be stopped after the gas pressure drops, and then annealed at 100℃ for 5min to obtain a MAPbI3 perovskite layer.

[0162] Step 4: Spin-coat [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on the perovskite layer at 1000 rpm / s, anneal at 100°C for 10 min, and then spin-coat its passivation layer bathocuproin (BCP) at 5000 rpm / s to obtain an electron transport layer.

[0163] Step 5, placing the wafer obtained in step 4 into a vapor deposition machine, and vapor depositing a copper electrode to 80 nm at a rate of 1 A / s to complete the preparation of the entire device.

[0164] Example 2

[0165] A solar cell includes a stacked ITO substrate, a hole transport layer, a perovskite layer, an electron transport layer and a copper electrode. The preparation steps are as follows:

[0166] Step 1: Take 20 pieces of ITO conductive glass with a specification of 2.0*2.0cm, remove 0.35cm of ITO at both ends by laser etching, and expose the glass substrate; ultrasonically clean the etched ITO conductive glass several times with water, acetone, and isopropanol in turn; blow the ITO conductive glass dry with a nitrogen gun, and put it into a UV ozone machine for further cleaning to obtain an ITO substrate treated with UV ozone;

[0167] Step 2: Spin-coat 2 mg / mL of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) at a rate of 5000 rpm / s on the UV-ozone treated ITO substrate, and anneal on a hot plate at 100° C. for 10 minutes to obtain a hole transport layer.

[0168] Step 3: Spin-coat 50uL of 1.4M lead iodide DMF solution on the hole transport layer at 3000rpm / s, treat at 100℃ for 1min to form a film layer containing lead iodide, and then place it in a gas-permeable sealed container, with the film layer facing up and fixed at the bottom of the sealed container, and let dry air + hydrogen iodide pass through. After the pressure rises to 1 standard atmosphere, invert the container, and then pass methylamine gas, and then add dry air to raise the total gas pressure to about 1.25 standard atmospheres to form an ambient atmosphere (including 0.125mol hydrogen iodide gas and 0.125mol methylamine gas). The ambient atmosphere is maintained at 20℃ for 5min, the reaction can be stopped after the pressure drops, and then annealed at 100℃ for 5min to obtain a MAPbI3 perovskite layer.

[0169] Step 4: Spin-coat [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on the perovskite layer at 1000 rpm / s, anneal at 100°C for 10 min, and then spin-coat its passivation layer bathocuproin (BCP) at 5000 rpm / s to obtain an electron transport layer.

[0170] Step 5: Place the wafer obtained in step 4 into a vapor deposition machine, and vapor-deposit the copper electrode to 80 nm at a rate of 1 A / s to complete the preparation of the entire device.

[0171] Example 3

[0172] A solar cell includes a stacked ITO substrate, a hole transport layer, a perovskite layer, an electron transport layer and a copper electrode. The preparation steps are as follows:

[0173] Step 1: Take 20 pieces of ITO conductive glass with a specification of 2.0*2.0cm, remove 0.35cm of ITO at both ends by laser etching, and expose the glass substrate; ultrasonically clean the etched ITO conductive glass several times with water, acetone, and isopropanol in turn; blow the ITO conductive glass dry with a nitrogen gun, and put it into a UV ozone machine for further cleaning to obtain an ITO substrate treated with UV ozone;

[0174] Step 2: Spin-coat 2 mg / mL of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) at a rate of 5000 rpm / s on the UV-ozone treated ITO substrate, and anneal on a hot plate at 100° C. for 10 minutes to obtain a hole transport layer.

[0175] Step 3: Spin-coat 50uL of 1.4M lead iodide DMF solution on the hole transport layer at 3000rpm / s, treat at 100℃ for 1min to form a film layer containing lead iodide, and then place it in a gas-permeable sealed container, with the film layer facing up and fixed at the bottom of the sealed container, and let dry air + hydrogen iodide pass through. After the pressure rises to 1 standard atmosphere, invert the container, and then pass methylamine gas, and then add dry air to raise the total gas pressure to about 1.25 standard atmospheres to form an ambient atmosphere (including 0.175mol hydrogen iodide gas and 0.175mol methylamine gas). The ambient atmosphere is maintained at 20℃ for 5min, the reaction can be stopped after the gas pressure drops, and then annealed at 100℃ for 5min to obtain a MAPbI3 perovskite layer.

[0176] Step 4: Spin-coat [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on the perovskite layer at 1000 rpm / s, anneal at 100°C for 10 min, and then spin-coat its passivation layer bathocuproin (BCP) at 5000 rpm / s to obtain an electron transport layer.

[0177] Step 5: Place the wafer obtained in step 4 into a vapor deposition machine, and vapor-deposit the copper electrode to 80 nm at a rate of 1 A / s to complete the preparation of the entire device.

[0178] Example 4

[0179] A solar cell includes a stacked ITO substrate, a hole transport layer, a perovskite layer, an electron transport layer and a copper electrode. The preparation steps are as follows:

[0180] Step 1: Take 20 pieces of ITO conductive glass with a specification of 2.0*2.0cm, remove 0.35cm of ITO at both ends by laser etching, and expose the glass substrate; ultrasonically clean the etched ITO conductive glass several times with water, acetone, and isopropanol in turn; blow the ITO conductive glass dry with a nitrogen gun, and put it into a UV ozone machine for further cleaning to obtain an ITO substrate treated with UV ozone;

[0181] Step 2: Spin-coat 2 mg / mL of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) at a rate of 5000 rpm / s on the UV-ozone treated ITO substrate, and anneal on a hot plate at 100° C. for 10 minutes to obtain a hole transport layer.

[0182] Step 3: Spin-coat 50uL of 1.4M lead iodide DMF solution on the hole transport layer at 3000rpm / s, treat at 100℃ for 1min to form a film layer containing lead iodide, and then place it in a sealed container that can pass gas, with the film layer facing up and fixed at the bottom of the sealed container, pass a mixed gas of dry air + hydrogen iodide + methylamine gas, and invert the container to raise the total air pressure of the sealed container to about 1.25 standard atmospheres. The mixed gas forms an ambient atmosphere (including 0.125mol hydrogen iodide gas and 0.125mol methylamine gas). The ambient atmosphere is maintained at 20℃ for 5min. The reaction can be stopped after the air pressure drops, and then annealed at 100℃ for 5min to obtain a MAPbI3 perovskite layer.

[0183] Step 4: Spin-coat [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on the perovskite layer at 1000 rpm / s, anneal at 100°C for 10 min, and then spin-coat its passivation layer bathocuproin (BCP) at 5000 rpm / s to obtain an electron transport layer.

[0184] Step 5: Place the wafer obtained in step 4 into a vapor deposition machine, and vapor-deposit the copper electrode to 80 nm at a rate of 1 A / s to complete the preparation of the entire device.

[0185] Example 5

[0186] A solar cell includes a stacked ITO substrate, a hole transport layer, a perovskite layer, an electron transport layer and a copper electrode. The preparation steps are as follows:

[0187] Step 1: Take 20 pieces of ITO conductive glass with a specification of 2.0*2.0cm, remove 0.35cm of ITO at both ends by laser etching, and expose the glass substrate; ultrasonically clean the etched ITO conductive glass several times with water, acetone, and isopropanol in turn; blow the ITO conductive glass dry with a nitrogen gun, and put it into a UV ozone machine for further cleaning to obtain an ITO substrate treated with UV ozone;

[0188] Step 2: Spin-coat 2 mg / mL of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) at a rate of 5000 rpm / s on the UV-ozone treated ITO substrate, and anneal on a hot plate at 100° C. for 10 minutes to obtain a hole transport layer.

[0189] Step 3: Spin-coat 50uL of 1.4M lead iodide DMF solution on the hole transport layer at 3000rpm / s, treat at 100℃ for 1min to form a film layer containing lead iodide, and then place it in a sealed container that can pass gas, with the film layer facing up and fixed at the bottom of the sealed container, and let dry air + hydrogen iodide pass through. After the pressure rises to 1 standard atmosphere, keep the container fixed (that is, the container is not inverted), and then pass methylamine gas, and then add dry air to raise the total gas pressure to about 1.25 standard atmospheres to form an ambient atmosphere (including 0.125mol hydrogen iodide gas and 0.125mol methylamine gas). The ambient atmosphere is maintained at 20℃ for 5min, the reaction can be stopped after the pressure drops, and then annealed at 100℃ for 5min to obtain a MAPbI3 perovskite layer.

[0190] Step 4: Spin-coat [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on the perovskite layer at 1000 rpm / s, anneal at 100°C for 10 min, and then spin-coat its passivation layer bathocuproin (BCP) at 5000 rpm / s to obtain an electron transport layer.

[0191] Step 5, placing the wafer obtained in step 4 into a vapor deposition machine, and vapor depositing a copper electrode to 80 nm at a rate of 1 A / s to complete the preparation of the entire device.

[0192] Comparative Example 1

[0193] A solar cell comprises a stacked ITO substrate, a hole transport layer, a perovskite layer, an electron transport layer and a copper electrode. Except for the different steps for preparing the perovskite layer, the other steps are the same as those in Example 1.

[0194] The steps for preparing the perovskite layer of this comparative example include: spin coating 1.4M MAPbI3 perovskite precursor solution on the hole transport layer at 3000 rpm / s, annealing at 100°C for 30 minutes, and cooling to room temperature to obtain the MAPbI3 perovskite layer.

[0195] Comparative Example 2

[0196] A solar cell comprises a stacked ITO substrate, a hole transport layer, a perovskite layer, an electron transport layer and a copper electrode. Except for the different steps for preparing the perovskite layer, the other steps are the same as those in Example 1.

[0197] The preparation steps of the perovskite layer in this comparative example include: spin coating a mixed solution containing 1.4M lead iodide and 1.4M hydrogen iodide on the hole transport layer at 3000rpm / s, drying at room temperature, placing in methylamine vapor for 20s, and then annealing at 100°C to obtain the MAPbI3 perovskite layer.

[0198] Performance Testing

[0199] (1) SEM morphology

[0200] The SEM morphology images of the perovskite layers in the solar cells of Examples 1-5 and Comparative Examples 1-2 are respectively: Figure 3-Figure 9 .from Figure 3-Figure 7 It can be seen that the perovskite film prepared in the embodiment of the present application has large grains and good uniformity. Figure 8-Figure 9 The perovskite film prepared in the comparative example shown has small grains and uneven particles.

[0201] (2) Under standard simulated sunlight (AM 1.5G, 100mW / cm 2 ) to test the efficiency of the battery under continuous illumination and to test its light stability.

[0202] a. Photovoltaic conversion efficiency test of perovskite solar cells:

[0203] In standard simulated sunlight (AM 1.5G, 100mW / cm 2 ) irradiation, the solar cell is tested to obtain the IV curve. According to the IV curve and the data fed back by the test equipment, the short-circuit current Jsc (unit: mA / cm 2 ), open circuit voltage Voc (unit V), maximum light output current Jmpp (unit mA) and maximum light output voltage Vmpp (unit V). The fill factor FF of the cell is calculated by the formula FF = Jsc × Voc / (Jmpp × Vmpp), unit %. The photoelectric conversion efficiency PCE of the cell is calculated by the formula PCE = Jsc × Voc × FF / Pw, unit %; Pw represents the input power, unit mW.

[0204] b. Perovskite solar cell stability test:

[0205] The prepared solar cell device was placed in a dry room at 65°C hot stage for accelerated testing, where the humidity was about 5%. The device efficiency was retested after 10 days, and the ratio of the efficiency to the initial efficiency was calculated. The specific experimental results are shown in Table 1.

[0206] Table 1

[0207] Implementation Photoelectric conversion efficiency (PCE, %) Ratio of 10-day efficiency to initial efficiency (%) Example 1 17.84 77.3 Example 2 18.36 82.0 Example 3 17.32 69.2 Example 4 16.57 59.8 Example 5 16.24 56.1 Comparative Example 1 16.15 53.7 Comparative Example 2 13.21 41.5

[0208] It can be seen from the test results in Table 1 that the perovskite film of the solar cell of the present application uses a unique preparation method. Compared with the comparative examples 1-2, the embodiments 1-5 of the present application not only have better light conversion efficiency, but also the efficiency stability of the solar cell device of the embodiments of the present application is better; further, by appropriately increasing the amount of HX gas and A deprotonated gas, the device performance can be further improved, and at the same time, inverting the sealed container for reaction can also further improve the device performance.

[0209] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A method for preparing a perovskite film, characterized in that: The steps include: Coating a solution containing BX2 or containing CX and DX3 on a substrate to form a film layer; Placing the film layer in an ambient atmosphere containing HX gas and A deprotonated gas to react and obtain a perovskite film; The perovskite chemical formula in the perovskite film includes ABX3 or A2CDX6, A is at least one monovalent organic cation, B is at least one divalent metal cation, C is at least one monovalent metal cation, D is at least one trivalent metal cation, and X is at least one monovalent anion.

2. The preparation method according to claim 1, characterized in that The step of placing the film layer in an ambient atmosphere containing HX gas and A deprotonated gas for reaction comprises: The substrate coated with the film layer is placed in a mixed gas containing the HX gas, and then the A deprotonated gas is introduced to form the ambient atmosphere for reaction.

3. The preparation method according to claim 2, before introducing the deprotonating gas A, the membrane layer is first turned downward, and then the deprotonating gas A is introduced under the membrane layer.

4. The preparation method according to claim 2, wherein the carrier gas in the mixed gas comprises at least one of air, nitrogen and argon.

5. The preparation method according to any one of claims 1 to 4, characterized in that: In the environment atmosphere containing HX gas and A deprotonated gas, the volume fraction of the HX gas in the total volume is 0.001% to 0.1%, and the volume fraction of the A deprotonated gas in the total volume is 0.001% to 0.1%.

6. The preparation method according to claim 5, characterized in that: The volume fraction of the HX gas in the total volume is 0.01% to 0.05%, and the volume fraction of the A deprotonated gas in the total volume is 0.01% to 0.05%.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The pressure of the ambient atmosphere is 1 to 1.25 standard atmospheres.

8. The preparation method according to any one of claims 1 to 7, characterized in that: The temperature for carrying out the reaction in the ambient atmosphere is 20-30°C.

9. The preparation method according to any one of claims 1 to 8, characterized in that: The reaction time in the ambient atmosphere is 2 to 10 minutes.

10. The preparation method according to any one of claims 1 to 9, characterized in that: After the reaction is carried out in the ambient atmosphere, an annealing treatment at 80-160° C. is further included.

11. The preparation method according to any one of claims 1 to 10, characterized in that: The molar ratio of the HX gas, the A deprotonated gas and the BX2 in the solution is (1-3): (1-3): 1; or, The ratio of the HX gas, the A deprotonated gas and the total molar amount of CX and DX3 in the solution is (1-3): (1-3):

1.

12. The preparation method according to any one of claims 1 to 11, characterized in that: The solution contains BX2, and the perovskite chemical formula in the obtained perovskite film is ABX3, Among them, A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of, B includes Pb 2+ Sn 2 + 、Be 2+ Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ 、Zn 2+ ,Ge 2+ , Fe 2+ 、Co 2+ and Ni 2+ At least one of X includes F - , Cl - Br - and I - At least one of .

13. The preparation method according to any one of claims 1 to 11, characterized in that: The solution contains CX and DX3, and the perovskite chemical formula in the obtained perovskite film is A2CDX6, Among them, A includes CH3NH3 + 、CH3CH2NH3 + 、CH3CH2CH2NH3 + and CH(NH2)2 + At least one of C including Ag + and Na + At least one of D includes Bi 3+ andIn 3+ At least one of X includes F - , Cl - Br - and I - At least one of .

14. The preparation method according to any one of claims 1 to 13, characterized in that: The HX gas is selected from at least one of HF, HCl, HBr and HI; and / or The deprotonated gas A is selected from at least one of CH3NH2, CH3CH2NH2, CH3CH2CH2NH2 and CH2(NH2)2.

15. A perovskite film, characterized in that: The perovskite film is prepared by the preparation method according to any one of claims 1 to 14.

16. The perovskite film according to claim 15, characterized in that The average particle size of the perovskite grains in the perovskite film is 700 to 900 nm.

17. A photoelectric device, characterized in that: The optoelectronic device comprises the perovskite film according to claim 15 or 16.

18. The optoelectronic device according to claim 17, characterized in that The photovoltaic device includes a solar cell.

19. The optoelectronic device according to claim 17 or 18, characterized in that: The photoelectric device comprises a stacked first electrode, a hole transport layer, a perovskite layer, an electron transport layer and a second electrode; wherein the perovskite layer contains the perovskite film.

20. A method for preparing a photoelectric device, characterized in that: include: The step of preparing a perovskite layer comprises: preparing a perovskite film by the preparation method according to any one of claims 1 to 14.

21. An electrical device, characterized in that: The electrical device comprises the optoelectronic device according to any one of claims 17-19.

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