A perovskite film and preparation method thereof, and a perovskite solar cell

Abstract

The present invention relates to the technical field of solar cells, and in particular to a perovskite film and a preparation method thereof, and a perovskite solar cell. The preparation method of the perovskite film comprises: providing a substrate; evaporating an inorganic phase on the substrate to form an inorganic film layer; evaporating an organic phase onto the inorganic film layer by thermal evaporation to form a perovskite film; wherein the inorganic phase comprises a first inorganic salt containing B-site ions and X-site ions in a perovskite material; the organic phase comprises formamidine hydrohalide, and ammonia is introduced during the process of evaporating the organic phase onto the inorganic film layer by thermal evaporation. The perovskite film prepared by the preparation method of the present invention has high repeatability, high overall uniformity of the film layer, and good quality. When applied to a perovskite solar cell, the effect of the actual components of the perovskite film deviating from the set components on the cell conversion efficiency and repeatability can be avoided, and the cell can be ensured to have high repeatability and good conversion efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a perovskite film and a preparation method thereof, and a perovskite solar cell. Background Art

[0002] Perovskite materials refer to compounds with ABX3 crystal structure. Due to their excellent optical and electrical properties, they show great application potential in solar cells, light-emitting diodes (LEDs) and other fields. However, the quality of perovskite films prepared by traditional methods (such as traditional solution method, thermal evaporation technology, etc.) is difficult to control or the precise control of film stoichiometry becomes difficult, which increases the complexity of the experiment.

[0003] At present, perovskite materials (MABX3) with methylammonium (MA) as the A-site ion are very popular in high-efficiency perovskite solar cells, but the volatility of methylammonium is not conducive to device stability, especially under heating conditions. In contrast, perovskite materials with formamidine (FA) and cesium (Cs) as the A-site ions show higher decomposition temperatures. When preparing the perovskite layer by thermal vapor deposition, the organic phase methylammonium salt cannot be well deposited on the substrate, while formamidine can be well monitored by the thickness monitor during the thermal evaporation process, so formamidine has gradually become a commonly used organic phase in thermal vapor deposition.

[0004] However, the inventors found that when the organic phase FAI is evaporated by thermal vapor deposition, the thickness detector cannot accurately monitor the evaporated thickness of the organic phase FAI, resulting in the amount of the obtained organic phase deviating from the calculated amount. The perovskite material thus obtained will seriously deviate from the calculated composition, thereby affecting the actual cell conversion efficiency and repeatability. Summary of the invention

[0005] The purpose of the present invention is to provide a perovskite film and a preparation method thereof, and a perovskite solar cell in view of the existing technical status.

[0006] The perovskite film preparation method of the present invention can better monitor the amount of the evaporated inorganic phase and the organic phase, especially can improve the accuracy of the thickness detector to monitor the evaporated thickness of the formamidine hydrohalide salt, reduce the difference between the set thickness of the organic phase and the actual evaporated thickness, and ensure that the perovskite component of the prepared perovskite film does not deviate. The perovskite film prepared by the preparation method of the present invention has high repeatability, high overall uniformity of the film layer, and good quality. It is applied to perovskite solar cells, and can avoid the influence of the actual components of the perovskite film deviating from the set components on the battery conversion efficiency and repeatability, and ensure that the battery has high repeatability and good conversion efficiency.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] The present invention provides a method for preparing a perovskite film, comprising:

[0009] Providing a substrate;

[0010] Vapor depositing an inorganic phase on the substrate to form an inorganic film layer;

[0011] Depositing the organic phase onto the inorganic film layer by thermal evaporation to form a perovskite film;

[0012] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in a perovskite material; the organic phase includes formamidine hydrohalide, and ammonia is introduced during the process of thermally evaporating the organic phase onto the inorganic film layer.

[0013] In the present invention, an inorganic film layer is prepared first, and then an organic phase is evaporated onto the inorganic film layer by thermal evaporation, so that the organic phase is combined with the inorganic film layer to form a perovskite film. The organic phase and the inorganic phase are evaporated step by step, and the amount of the evaporated inorganic phase and the organic phase can be better monitored; on the other hand, in the organic phase evaporation process, ammonia is introduced to suppress the decomposition of the formamidine hydrohalide salt during the evaporation process, thereby effectively reducing the monitoring interference caused by the thermal decomposition of the formamidine hydrohalide salt to the thickness detector, improving the accuracy of the thickness detector to monitor the evaporation thickness of the formamidine hydrohalide salt, reducing the difference between the set thickness of the organic phase and the actual evaporation thickness, and ensuring that the perovskite component of the obtained perovskite film does not deviate. Thus, the perovskite film obtained by the preparation method of the present invention has high repeatability, high overall uniformity of the film layer, good quality, and is applied to perovskite solar cells. The actual components of the perovskite film can be avoided from deviating from the set components on the battery conversion efficiency and repeatability, ensuring that the battery has high repeatability and good conversion efficiency.

[0014] In some embodiments, the flux of the ammonia gas is 10 sccm to 200 sccm.

[0015] The present invention can enhance the inhibitory effect on the decomposition of formamidine hydrohalide by reasonably setting the amount of ammonia gas introduced, and can reasonably control the cost.

[0016] In some embodiments, in the step of depositing the organic phase onto the inorganic film layer by thermal evaporation, the deposition rate is The evaporation temperature is 100°C to 200°C.

[0017] The present invention reasonably sets the plating rate range of the organic phase so that the introduced ammonia gas can more effectively inhibit the decomposition phenomenon in the evaporation process of the formamidine hydrohalide salt, and at the same time, the uniformity and quality of the prepared perovskite film are better.

[0018] In some embodiments, the formamidine hydrohalide salt is any one or more of formamidine hydroiodide, formamidine hydrochloride and formamidine hydrobromide.

[0019] The present invention can enhance the inhibitory effect on the decomposition of formamidine hydroiodide when ammonia is introduced by setting the formamidine hydrohalide salt to any one or more of formamidine hydroiodide, formamidine hydrochloride and formamidine hydrobromide, and is more conducive to reducing the difference between the set thickness of the organic phase and the actual evaporation thickness.

[0020] In some embodiments, the B-site ion is a metal ion, and the X-site ion is a halogen ion.

[0021] In some embodiments, the B-site ion is Mn 2+ Sn 2+ or Pb 2+ , the X-site ion is I - , Cl - Br - Any one or more of .

[0022] In some embodiments, the first inorganic salt includes one or more of SnI2, SnCl2, SnBr2, PbI2, PbCl2, and PbBr2.

[0023] In some embodiments, the inorganic phase further includes a second inorganic salt containing A-site ions and X-site ions in the perovskite material.

[0024] In some embodiments, the second inorganic salt includes one or more of CsBr, CsI, and CsCl.

[0025] In some embodiments, including:

[0026] After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is lower than a preset threshold, and then the substrate is taken out.

[0027] In some embodiments, including:

[0028] After the organic phase evaporation is completed, the substrate is annealed to form a perovskite film. The annealing temperature of the annealing treatment is 140° C. to 170° C., and the annealing time is 10 min to 40 min.

[0029] The present invention also provides a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0030] The present invention also provides a perovskite solar cell, comprising a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0031] In some embodiments, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer and a metal electrode sequentially disposed on the substrate.

[0032] In some embodiments, the solar cell includes a substrate and an electron transport layer, a perovskite film, a hole transport layer and a metal electrode sequentially disposed on the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The present invention is a flowchart of a method for preparing a perovskite film according to an embodiment of the present invention.

[0034] Figure 2 Flow chart of step S330 of an embodiment of the present invention.

[0035] Figure 3 Schematic diagram of the structure of a perovskite solar cell according to an embodiment of the present invention.

[0036] Figure 4 Flow chart of a method for preparing a perovskite solar cell (inverted structure) according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. Examples of embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be construed as limiting the present invention. In addition, it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0038] In the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0039] See also Figure 1 As shown, the present invention provides a method for preparing a perovskite film, comprising:

[0040] S310. Providing a substrate;

[0041] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0042] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film;

[0043] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and ammonia is introduced during the process of thermal evaporation of the organic phase onto the inorganic film layer, wherein the introduced ammonia is dry ammonia.

[0044] Experiments have found that during the thermal evaporation process, as the temperature rises, the formamidine hydrohalide will decompose. The by-products generated by the decomposition will affect the accuracy of the thickness detector in monitoring the evaporation thickness of the organic phase, resulting in inaccurate and large fluctuations in the thickness measured by the thickness detector.

[0045] Specifically, taking formamidine hydroiodide as an example, its thermal decomposition reaction is mainly as follows:

[0046]

[0047] In the present invention, the characteristic that ammonia gas will be generated by thermal decomposition of formamidine hydrohalide salt is utilized, and ammonia gas is introduced during the thermal evaporation and evaporation of formamidine hydrohalide salt, thereby inhibiting the decomposition of formamidine hydrohalide salt during the evaporation and evaporation process, thereby effectively reducing the monitoring interference of the thickness detector caused by the thermal decomposition of the formamidine hydrohalide salt, and improving the accuracy of the thickness detector in monitoring the evaporation thickness of the formamidine hydrohalide salt.

[0048] In the present invention, on the one hand, an inorganic film layer is prepared first, and then the organic phase is evaporated onto the inorganic film layer by thermal evaporation, so that the organic phase is combined with the inorganic film layer to form a perovskite film. The organic phase and the inorganic phase are evaporated step by step, and the amount of the evaporated inorganic phase and the organic phase can be better monitored; on the other hand, during the evaporation of the organic phase, ammonia is introduced to suppress the decomposition of the formamidine hydrohalide salt during the evaporation process, thereby effectively reducing the monitoring interference caused by the thermal decomposition of the formamidine hydrohalide salt to the thickness detector, improving the accuracy of the thickness detector to monitor the evaporation thickness of the formamidine hydrohalide salt, reducing the difference between the set thickness of the organic phase and the actual evaporation thickness, and ensuring that the perovskite component of the obtained perovskite film does not deviate. Thus, the perovskite film obtained by the preparation method of the present invention has high repeatability, high overall uniformity of the film layer, good quality, and is applied to perovskite solar cells. It can avoid the influence of the actual components of the perovskite film deviating from the set components on the battery conversion efficiency and repeatability, and ensure that the battery has high repeatability and good conversion efficiency.

[0049] It is understandable that the substrate refers to the material on which the perovskite film is to be set. The substrate can be a single-layer material or a material composed of multiple layers of materials. In some embodiments, the substrate as the basis of the perovskite cell can adopt a transparent conductive substrate, which is usually made of materials such as fluorine-doped tin oxide (FTO) or indium-doped tin oxide (ITO), and has high light transmittance and good conductivity. Its main function is to introduce sunlight and collect the generated current. The choice of transparent conductive substrate is crucial to the performance of perovskite solar cells because it not only affects the incidence of light, but also affects the derivation of current.

[0050] In some embodiments, the flux of ammonia gas is 10 sccm to 200 sccm.

[0051] Exemplarily, the flux of ammonia gas can be set to 10sccm, 15sccm, 20sccm, 25sccm, 30sccm, 40sccm, 50sccm, 60sccm, 70sccm, 80sccm, 90sccm, 100sccm, 120sccm, 150sccm, 160sccm, 180sccm or 200sccm, but is not limited thereto.

[0052] When too little ammonia is introduced, the inhibitory effect on the decomposition of the formamidine hydrohalide salt is limited, and when too much ammonia is introduced, the cost is increased. Therefore, by reasonably setting the amount of ammonia introduced, the inhibitory effect on the decomposition of the formamidine hydrohalide salt can be enhanced, and the cost can be reasonably controlled.

[0053] In some embodiments, in the step of depositing the organic phase onto the inorganic film layer by thermal evaporation, the deposition rate is The evaporation temperature is 100°C to 200°C.

[0054] For example, the plating rate can be set to or When the organic phase is within this plating rate range, the introduced ammonia gas can more effectively inhibit the decomposition of the formamidine hydrohalide during the evaporation process, and at the same time, the uniformity and quality of the obtained perovskite film are better.

[0055] Exemplarily, the evaporation temperature is 100° C., 110° C., 120° C., 130° C., 140° C., 150° C., 160° C., 170° C., 180° C., 190° C. or 200° C., but not limited thereto. Within this evaporation temperature, it is beneficial to improve the stability of the evaporation rate and to inhibit the decomposition of the formamidine hydrohalide salt during the evaporation process.

[0056] In some embodiments, in the step of evaporating the inorganic phase onto the substrate, the coating rate is The uniformity and quality of the prepared inorganic film layer are better.

[0057] In some embodiments, the formamidine hydrohalide salt is any one or more of formamidine hydroiodide (FAI), formamidine hydrochloride (FACl) and formamidine hydrobromide (FABr).

[0058] In some embodiments, preferably, the formamidine hydrohalide salt is any one or more of formamidine hydroiodide and formamidine hydrobromide.

[0059] In some embodiments, more preferably, the formamidine hydrohalide salt is formamidine hydroiodide, and the introduction of ammonia gas has a better inhibitory effect on the decomposition of formamidine hydroiodide, which is more conducive to reducing the difference between the set thickness of the organic phase and the actual evaporation thickness.

[0060] In some embodiments, the B-site ion is a metal ion and the X-site ion is a halogen ion.

[0061] In some embodiments, preferably, the B-site ion is Mn 2+ Sn 2+ or Pb 2+ , X-site ion is I - , Cl - Br - Any one or more of .

[0062] It is understandable that introducing an appropriate amount of Sn into the perovskite film 2+ Replacement of Pb 2+ , can reduce the toxicity of perovskite films, but Sn 2+ The stability is poor. Based on the battery efficiency and stability, in some embodiments, it is more preferred that the B-site ion is Pb 2+ , the obtained perovskite film has better stability.

[0063] In some embodiments, the first inorganic salt includes one or more of SnI2, SnCl2, SnBr2, PbI2, PbCl2, PbBr2, but is not limited thereto.

[0064] In some embodiments, preferably, the first inorganic salt includes one or more of PbI2, PbCl2, and PbBr2.

[0065] In some embodiments, the inorganic phase further includes a second inorganic salt containing A-site ions and X-site ions in the perovskite material.

[0066] In some embodiments, the second inorganic salt includes one or more of CsBr, CsI, and CsCl.

[0067] It can be understood that when the inorganic phase is the first inorganic salt, the perovskite component of the obtained perovskite film can be FAPbI3, FAPbBr3, FAPbCl3, FAPbI 3-x Br x , FAPbI 3-x Cl x 、FASnI3、FAPb y Sn 1-y I3 or FAPb y Sn 1-y I 3- x Br x When the inorganic phase includes the first inorganic salt and the second inorganic salt, the perovskite component of the obtained perovskite film may be Cs z FA 1-z PbI3、Cs z FA 1-z PbBr3 or Cs z FA 1-z PbCl3, but not limited thereto.

[0068] In some embodiments, see Figure 2 As shown, including:

[0069] S332. After the organic phase evaporation is completed, stop introducing ammonia gas, and introduce nitrogen gas into the chamber to remove ammonia gas in the equipment chamber until the ammonia gas in the equipment chamber is lower than a preset threshold value, and then take out the substrate.

[0070] In some embodiments, see Figure 2 As shown, including:

[0071] S333. Perform annealing treatment on the substrate to form a perovskite film. The annealing temperature of the annealing treatment is 140° C. to 170° C., and the annealing time is 10 min to 40 min.

[0072] Exemplarily, the annealing temperature is 140° C., 145° C., 150° C., 155° C., 160° C., 165° C. or 170° C., but not limited thereto. The retreat time is 10 min, 15 min, 20 min, 25 min, 30 min, 35 min or 40 min, but not limited thereto.

[0073] Through the above annealing treatment, the inorganic phase and the organic phase that are successively evaporated form a perovskite film with high uniformity on the substrate.

[0074] For example, see Figure 2 As shown, in step S330, the steps of depositing the organic phase onto the inorganic film layer by thermal evaporation to form a perovskite film are as follows:

[0075] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0076] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the chamber of the device until the ammonia in the chamber of the device is lower than the preset threshold, and the substrate is removed;

[0077] S333. Annealing the substrate to form a perovskite film.

[0078] In some embodiments, preferably, the preset threshold is 0.1 ppm.

[0079] The present invention also provides a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0080] The perovskite film prepared by the preparation method of the present invention has high repeatability and good overall film quality.

[0081] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0082] The perovskite film prepared by the preparation method of the present invention is applied to perovskite solar cells, which can avoid the influence of the actual components of the perovskite film deviating from the set components on the cell conversion efficiency and repeatability, and ensure that the cell has high repeatability and good conversion efficiency.

[0083] In one embodiment, see Figure 3 As shown, the solar cell includes a substrate 1 and a hole transport layer 2, a perovskite film 3, an electron transport layer 5 and a metal electrode 6 which are sequentially arranged on the substrate.

[0084] Exemplarily, the thickness of the perovskite film is 20 nm to 900 nm, but is not limited thereto.

[0085] In some embodiments, see Figure 3 As shown, preferably, a buffer layer 4 is provided between the electron transport layer and the metal electrode layer. More preferably, the material of the buffer layer may be SnO x Or BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), the buffer layer can be prepared by atomic layer deposition or vacuum coating. Preferably, the thickness is 1nm to 30nm, and the coating rate is

[0086] In another embodiment, a solar cell includes a substrate and an electron transport layer, a perovskite film, a hole transport layer and a metal electrode sequentially disposed on the substrate.

[0087] In some embodiments, the substrate includes a transparent conductive layer.

[0088] Among them, the hole transport layer provides an efficient hole transport channel to promote the transport of holes. The electron transport layer has the functions of transporting electrons, inhibiting electron convergence, and blocking holes. The perovskite film, as a light absorption layer, has good light absorption performance and photoelectric conversion efficiency.

[0089] In some embodiments, the material of the hole transport layer can be an inorganic material or an organic material. For example, the material of the hole transport layer is a semiconductor nickel oxide (NiO x ) or [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphoric acid (Me-4PACz), Spiro-OMeTAD, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine (PTAA), but not limited thereto. The hole transport layer can be prepared by vacuum coating, for example, thermal evaporation or magnetron sputtering. Preferably, the thickness is 1nm to 40nm, and the coating rate is

[0090] In some embodiments, the material of the electron transport layer can be an inorganic material or an organic material. For example, the material of the electron transport layer is tin oxide (SnO x ), titanium dioxide (TiO2), zinc oxide (ZnO), aluminum oxide (Al2O3), tungsten trioxide (WO3) or carbon 60 (C 60 ), but not limited thereto. The electron transport layer can be prepared by vacuum coating, for example, thermal evaporation or magnetron sputtering. Preferably, the thickness is 5nm to 50nm, and the coating rate is

[0091] In some embodiments, see Figure 1 , Figure 2 and Figure 4 As shown, a method for preparing a solar cell provided in an embodiment of the present invention is as follows:

[0092] S100. Clean the surface of the substrate to make the processed side surface clean.

[0093] S200. Preparation of hole transport layer:

[0094] Exemplarily, the material of the hole transport layer is NiO x or Me-4PACz, can be prepared by vacuum coating, for example, thermal evaporation or magnetron sputtering. Preferably, the thickness is 1nm to 40nm, and the coating rate is

[0095] S300. Preparation of perovskite film:

[0096] S310. Providing a substrate (a substrate on which a hole transport layer is evaporated as a substrate);

[0097] S320. Evaporating an inorganic phase on the hole transport layer to form an inorganic film layer;

[0098] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0099] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0100] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and ammonia is introduced during the process of thermal evaporation of the organic phase onto the inorganic film layer;

[0101] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the chamber of the device until the ammonia in the chamber of the device is lower than the preset threshold, and the substrate is removed;

[0102] S333. Annealing the substrate to form a perovskite film.

[0103] S400. Preparation of electron transport layer:

[0104] Exemplarily, the material of the electron transport layer is SnO x or C 60 , can be prepared by vacuum coating method, for example, thermal evaporation or magnetron sputtering. Preferably, the thickness is 5nm to 50nm, and the coating rate is

[0105] S500. Preparation of buffer layer:

[0106] For example, the material of the buffer layer may be SnO x Or BCP, the buffer layer can be prepared by atomic layer deposition or vacuum coating. Preferably, the thickness is 1nm to 30nm, and the coating rate is

[0107] S600. Preparation of metal electrodes:

[0108] Exemplarily, the material of the metal electrode may be one or more of copper, tin, aluminum, silver, gold, chromium, iron, nickel, zinc, ruthenium, palladium, and platinum, but is not limited thereto. Preferably, the material of the metal electrode is silver, which can be prepared by vacuum evaporation or screen printing.

[0109] It is understandable that the perovskite solar cell in the embodiment of the present invention can be set to an upright structure or an inverted structure. When set to an upright structure, the step of preparing the electron transport layer in S400 can be performed first, and then the step of preparing the hole transport layer in S200 can be performed. Similarly, when set to an inverted structure, such as Figure 4As shown, the step of forming a hole transport layer in S200 may be performed first, and then the step of forming an electron transport layer in S400 may be performed. Therefore, S200 and S400 in the above steps may be interchangeable.

[0110] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0111] Example 1

[0112] The present invention provides a specific method for preparing a perovskite film, comprising:

[0113] S310. Providing a substrate;

[0114] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0115] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0116] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0117] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and in the process of thermally evaporating the organic phase onto the inorganic film layer, dry ammonia gas is introduced, the ammonia gas flux is 10 sccm, and the plating rate is The evaporation temperature is 120°C;

[0118] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is less than 0.1 ppm, and the substrate is removed;

[0119] S333. Anneal the substrate at a temperature of 150° C. for 20 minutes to form a perovskite film.

[0120] In this embodiment, the formamidine hydrohalide salt is formamidine hydroiodide (FAI).

[0121] In this embodiment, the inorganic phase is a first inorganic salt, and the first inorganic salt is PbI2.

[0122] The perovskite component of the prepared perovskite film is FAPbI3.

[0123] This embodiment also discloses a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0124] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0125] In this embodiment, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a metal electrode which are sequentially arranged on the substrate.

[0126] In this embodiment, the substrate includes a transparent conductive layer.

[0127] The preparation method of the above solar cell is as follows:

[0128] S100. Clean the surface of the substrate to make the processed side surface clean.

[0129] S200. Preparation of hole transport layer: The material of the hole transport layer is NiO x , thickness is 20nm.

[0130] S300. Preparing a perovskite film: For details, refer to the above-mentioned method for preparing a perovskite film.

[0131] S400. Prepare the electron transport layer: the material of the electron transport layer is C 60 , thickness is 30nm.

[0132] S500. Prepare a buffer layer: the material of the buffer layer is BCP, and the thickness is 15 nm.

[0133] S600. Prepare metal electrode: The material of the metal electrode is Ag.

[0134] Example 2

[0135] The present invention provides another specific method for preparing a perovskite film, comprising:

[0136] S310. Providing a substrate;

[0137] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0138] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0139] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0140] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and in the process of thermally evaporating the organic phase onto the inorganic film layer, dry ammonia gas is introduced, the ammonia gas flux is 100 sccm, and the plating rate is The evaporation temperature is 120°C;

[0141] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is less than 0.1 ppm, and the substrate is removed;

[0142] S333. Anneal the substrate at a temperature of 150° C. for 20 minutes to form a perovskite film.

[0143] In this embodiment, the formamidine hydrohalide salt is formamidine hydroiodide (FAI).

[0144] In this embodiment, the inorganic phase is a first inorganic salt, and the first inorganic salt is PbI2.

[0145] The perovskite component of the prepared perovskite film is FAPbI3.

[0146] This embodiment also discloses a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0147] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0148] In this embodiment, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a metal electrode which are sequentially arranged on the substrate.

[0149] In this embodiment, the substrate includes a transparent conductive layer.

[0150] The preparation method of the above solar cell is as follows:

[0151] S100. Clean the surface of the substrate to make the processed side surface clean.

[0152] S200. Preparation of hole transport layer: The material of the hole transport layer is NiO x , thickness is 20nm.

[0153] S300. Preparing a perovskite film: For details, refer to the above-mentioned method for preparing a perovskite film.

[0154] S400. Prepare the electron transport layer: the material of the electron transport layer is C 60 , thickness is 30nm.

[0155] S500. Prepare a buffer layer: the material of the buffer layer is BCP, and the thickness is 15 nm.

[0156] S600. Prepare metal electrode: The material of the metal electrode is Ag.

[0157] Example 3

[0158] The present invention provides another specific method for preparing a perovskite film, comprising:

[0159] S310. Providing a substrate;

[0160] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0161] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0162] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0163] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and in the process of thermally evaporating the organic phase onto the inorganic film layer, dry ammonia gas is introduced, the ammonia gas flux is 200 sccm, and the plating rate is The evaporation temperature is 120°C;

[0164] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is less than 0.1 ppm, and the substrate is removed;

[0165] S333. Anneal the substrate at a temperature of 150° C. for 20 minutes to form a perovskite film.

[0166] In this embodiment, the formamidine hydrohalide salt is formamidine hydroiodide (FAI).

[0167] In this embodiment, the inorganic phase is a first inorganic salt, and the first inorganic salt is PbI2.

[0168] The perovskite component of the prepared perovskite film is FAPbI3.

[0169] This embodiment also discloses a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0170] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0171] In this embodiment, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a metal electrode which are sequentially arranged on the substrate.

[0172] In this embodiment, the substrate includes a transparent conductive layer.

[0173] The preparation method of the above solar cell is as follows:

[0174] S100. Clean the surface of the substrate to make the processed side surface clean.

[0175] S200. Preparation of hole transport layer: The material of the hole transport layer is NiO x, thickness is 20nm.

[0176] S300. Preparing a perovskite film: For details, refer to the above-mentioned method for preparing a perovskite film.

[0177] S400. Prepare the electron transport layer: the material of the electron transport layer is C 60 , thickness is 30nm.

[0178] S500. Prepare a buffer layer: the material of the buffer layer is BCP, and the thickness is 15 nm.

[0179] S600. Prepare metal electrode: The material of the metal electrode is Ag.

[0180] Example 4

[0181] The present invention provides another specific method for preparing a perovskite film, comprising:

[0182] S310. Providing a substrate;

[0183] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0184] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0185] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0186] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and in the process of thermally evaporating the organic phase onto the inorganic film layer, dry ammonia gas is introduced, the ammonia gas flux is 200 sccm, and the plating rate is The evaporation temperature is 170°C;

[0187] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is less than 0.1 ppm, and the substrate is removed;

[0188] S333. Anneal the substrate at a temperature of 150° C. for 20 minutes to form a perovskite film.

[0189] In this embodiment, the formamidine hydrohalide salt is formamidine hydroiodide (FAI).

[0190] In this embodiment, the inorganic phase is a first inorganic salt, and the first inorganic salt is PbI2.

[0191] The perovskite component of the prepared perovskite film is FAPbI3.

[0192] This embodiment also discloses a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0193] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0194] In this embodiment, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a metal electrode which are sequentially arranged on the substrate.

[0195] In this embodiment, the substrate includes a transparent conductive layer.

[0196] The preparation method of the above solar cell is as follows:

[0197] S100. Clean the surface of the substrate to make the processed side surface clean.

[0198] S200. Preparation of hole transport layer: The material of the hole transport layer is NiO x , thickness is 20nm.

[0199] S300. Preparing a perovskite film: For details, refer to the above-mentioned method for preparing a perovskite film.

[0200] S400. Prepare the electron transport layer: the material of the electron transport layer is C 60 , thickness is 30nm.

[0201] S500. Prepare a buffer layer: the material of the buffer layer is BCP, and the thickness is 15 nm.

[0202] S600. Prepare metal electrode: The material of the metal electrode is Ag.

[0203] Example 5

[0204] The present invention provides another specific method for preparing a perovskite film, comprising:

[0205] S310. Providing a substrate;

[0206] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0207] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0208] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0209] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and in the process of thermally evaporating the organic phase onto the inorganic film layer, dry ammonia gas is introduced, the ammonia gas flux is 100 sccm, and the plating rate is The evaporation temperature is 120°C;

[0210] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is less than 0.1 ppm, and the substrate is removed;

[0211] S333. Anneal the substrate at a temperature of 150° C. for 20 minutes to form a perovskite film.

[0212] In this embodiment, the formamidine hydrohalide salt is formamidine hydroiodide (FAI).

[0213] In this embodiment, the inorganic phase includes a first inorganic salt and a second inorganic salt, the first inorganic salt is PbI2, and the second inorganic salt is CsI.

[0214] The perovskite component of the prepared perovskite film is Cs z FA 1-z PbI3.

[0215] This embodiment also discloses a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0216] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0217] In this embodiment, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a metal electrode which are sequentially arranged on the substrate.

[0218] In this embodiment, the substrate includes a transparent conductive layer.

[0219] The preparation method of the above solar cell is as follows:

[0220] S100. Clean the surface of the substrate to make the processed side surface clean.

[0221] S200. Preparation of hole transport layer: The material of the hole transport layer is NiO x , thickness is 20nm.

[0222] S300. Preparing a perovskite film: For details, refer to the above-mentioned method for preparing a perovskite film.

[0223] S400. Prepare the electron transport layer: the material of the electron transport layer is C60 , thickness is 30nm.

[0224] S500. Prepare a buffer layer: the material of the buffer layer is BCP, and the thickness is 15 nm.

[0225] S600. Prepare metal electrode: The material of the metal electrode is Ag.

[0226] Example 6

[0227] The present invention provides another specific method for preparing a perovskite film, comprising:

[0228] S310. Providing a substrate;

[0229] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0230] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0231] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0232] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and in the process of thermally evaporating the organic phase onto the inorganic film layer, dry ammonia gas is introduced, the ammonia gas flux is 100 sccm, and the plating rate is The evaporation temperature is 120°C;

[0233] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is less than 0.1 ppm, and the substrate is removed;

[0234] S333. Anneal the substrate at a temperature of 150° C. for 20 minutes to form a perovskite film.

[0235] In this embodiment, the formamidine hydrohalide salt is formamidine hydrobromide (FABr).

[0236] In this embodiment, the inorganic phase includes a first inorganic salt and a second inorganic salt, the first inorganic salt is PbBr2, and the second inorganic salt is CsBr.

[0237] The perovskite component of the prepared perovskite film is Cs z FA 1-z PbBr3.

[0238] This embodiment also discloses a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0239] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0240] In this embodiment, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a metal electrode which are sequentially arranged on the substrate.

[0241] In this embodiment, the substrate includes a transparent conductive layer.

[0242] The preparation method of the above solar cell is as follows:

[0243] S100. Clean the surface of the substrate to make the processed side surface clean.

[0244] S200. Preparation of hole transport layer: The material of the hole transport layer is NiO x , thickness is 20nm.

[0245] S300. Preparing a perovskite film: For details, refer to the above-mentioned method for preparing a perovskite film.

[0246] S400. Prepare the electron transport layer: the material of the electron transport layer is C 60 , thickness is 30nm.

[0247] S500. Prepare a buffer layer: the material of the buffer layer is BCP, and the thickness is 15 nm.

[0248] S600. Prepare metal electrode: The material of the metal electrode is Ag.

[0249] Example 7

[0250] The present invention provides another specific method for preparing a perovskite film, comprising:

[0251] S310. Providing a substrate;

[0252] S320. Evaporating the inorganic phase on the substrate to form an inorganic film layer;

[0253] S330. The organic phase is deposited onto the inorganic film layer by thermal evaporation to form a perovskite film:

[0254] S331. The organic phase is deposited onto the inorganic film layer by thermal evaporation;

[0255] The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in the perovskite material; the organic phase includes formamidine hydrohalide, and in the process of thermally evaporating the organic phase onto the inorganic film layer, dry ammonia gas is introduced, the ammonia gas flux is 100 sccm, and the plating rate is The evaporation temperature is 120°C;

[0256] S332. After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is less than 0.1 ppm, and the substrate is removed;

[0257] S333. Anneal the substrate at a temperature of 150° C. for 20 minutes to form a perovskite film.

[0258] In this embodiment, the formamidine hydrohalide salt is formamidine hydroiodide (FAI).

[0259] In this embodiment, the inorganic phase is a first inorganic salt, and the first inorganic salt is PbI2 and SnBr2.

[0260] The perovskite component of the prepared perovskite film is FAPb y Sn 1-y I z Br 3-z .

[0261] This embodiment also discloses a perovskite film, which is prepared by the above-mentioned method for preparing a perovskite film.

[0262] A perovskite solar cell comprises a perovskite film prepared by the above-mentioned method for preparing a perovskite film.

[0263] In this embodiment, the solar cell includes a substrate and a hole transport layer, a perovskite film, an electron transport layer, a buffer layer and a metal electrode which are sequentially arranged on the substrate.

[0264] In this embodiment, the substrate includes a transparent conductive layer.

[0265] The preparation method of the above solar cell is as follows:

[0266] S100. Clean the surface of the substrate to make the processed side surface clean.

[0267] S200. Preparation of hole transport layer: The material of the hole transport layer is NiO x , thickness is 20nm.

[0268] S300. Preparing a perovskite film: For details, refer to the above-mentioned method for preparing a perovskite film.

[0269] S400. Prepare the electron transport layer: the material of the electron transport layer is C 60 , thickness is 30nm.

[0270] S500. Prepare a buffer layer: the material of the buffer layer is BCP, and the thickness is 15 nm.

[0271] S600. Prepare metal electrode: The material of the metal electrode is Ag.

[0272] Comparative Example 1

[0273] The difference between this comparative example and Example 1 is that in step S330, ammonia gas is not introduced during the process of depositing the organic phase onto the inorganic film layer by thermal evaporation.

[0274] 1. On-chip uniformity test:

[0275] 1) Experimental group: Examples 1 to 4 and Comparative Example 1

[0276] 2) Test method:

[0277] The perovskite film was prepared by the preparation method in each experimental group, and the thickness was set to 500 nm. Five test points were taken corresponding to the perovskite film in each experimental group, and the actual thickness was tested at the five test positions. The intra-sheet uniformity u1 of each experimental group was calculated. The calculation formula of u1 is as follows:

[0278] u1=100%×(h max -h min ) / h1, where h max is the maximum thickness of each test point, h min is the minimum thickness of each test point, and h1 is the average thickness of each test point.

[0279] 3) The test results are shown in Table 1 below:

[0280] Table 1 In-chip uniformity test results

[0281] Experimental Group Uniformity within the chip (%) Example 1 98.65 Example 2 99.12 Example 3 98.29 Example 4 99.23 Comparative Example 1 96.67

[0282] 2. Inter-chip uniformity test:

[0283] 1) Experimental group: Examples 1 to 4 and Comparative Example 1

[0284] 2) Test method:

[0285] a. The perovskite films were prepared using the preparation methods in each experimental group. Five test points were taken for each perovskite film. The actual thickness was tested at the five test positions and the average value was taken as the thickness of each perovskite film. Ten perovskite films were prepared in each experimental group and the inter-sheet uniformity u2 of the ten perovskite films was measured. The calculation formula for u2 is as follows:

[0286] u2=100%×(h max -h min ) / h2, where h max is the maximum thickness of the 10 perovskite films in each group, h minis the minimum thickness value among the 10 perovskite films in each group, and h2 is the average value of the 10 perovskite films in each group.

[0287] b. Test the conversion efficiency of the batteries prepared in each experimental group. The conversion efficiency here is the average conversion efficiency of 10 batteries in each group.

[0288] 3) The test results are shown in Table 2 below:

[0289] Table 2 Inter-chip uniformity and conversion efficiency test results

[0290]

[0291]

[0292] By comparing Examples 1 to 4 with Comparative Example 1, it can be seen that the inter-sheet uniformity and intra-sheet uniformity of the perovskite film prepared by Examples 1 to 4 using the preparation method of the present invention are significantly better than those of Comparative Example 1, which shows that the perovskite film prepared by the preparation method of the present invention has better uniformity and high repeatability. Among them, by comparing Examples 1 to 4, it can be seen that the uniformity and quality of the film can be improved by the mutual coordination between the amount of ammonia gas introduced and the organic phase plating rate.

[0293] Secondly, the conversion efficiency of the batteries prepared in Examples 1 to 4 is much higher than that in Comparative Example 1. It can be seen that the perovskite film prepared by the preparation method of the present invention is applied to batteries, which can effectively improve the conversion efficiency of the batteries.

[0294] Experimental results show that the perovskite film prepared by the preparation method of the present invention has better uniformity, a small deviation between the actual thickness and the set thickness, and the prepared perovskite film has high repeatability and good quality, which is beneficial to improving the repeatability and conversion efficiency of the battery.

[0295] In the description of this specification, the description with reference to the terms "some embodiments", "exemplary", "example", or "for example" means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0296] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with the field can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A method for preparing a perovskite film, characterized in that: include: Providing a substrate; Vapor depositing an inorganic phase on the substrate to form an inorganic film layer; Depositing the organic phase onto the inorganic film layer by thermal evaporation to form a perovskite film; The inorganic phase includes a first inorganic salt containing B-site ions and X-site ions in a perovskite material; the organic phase includes formamidine hydrohalide, and ammonia is introduced during the process of thermally evaporating the organic phase onto the inorganic film layer.

2. The method for preparing a perovskite thin film according to claim 1, characterized in that: The flux of the ammonia gas is 10 sccm to 200 sccm.

3. The method for preparing a perovskite thin film according to claim 1, characterized in that: In the step of depositing the organic phase onto the inorganic film layer by thermal evaporation, the plating rate is The evaporation temperature is 100°C to 200°C.

4. The method for preparing a perovskite thin film according to claim 1, characterized in that: The formamidine hydrohalide salt is any one or more of formamidine hydroiodide, formamidine hydrochloride and formamidine hydrobromide.

5. The method for preparing a perovskite thin film according to claim 1, characterized in that: The B-site ions are metal ions, and the X-site ions are halogen ions.

6. The method for preparing a perovskite thin film according to claim 5, characterized in that: The B-site ion is Mn 2 + Sn 2+ or Pb 2+ , the X-site ion is I - , Cl - Br - Any one or more of .

7. The method for preparing a perovskite thin film according to claim 1, characterized in that: The first inorganic salt includes one or more of SnI2, SnCl2, SnBr2, PbI2, PbCl2, and PbBr2.

8. The method for preparing a perovskite thin film according to claim 1, characterized in that: The inorganic phase further includes a second inorganic salt containing A-site ions and X-site ions in the perovskite material.

9. The method for preparing a perovskite thin film according to claim 8, characterized in that: The second inorganic salt includes one or more of CsBr, CsI, and CsCl.

10. The method for preparing a perovskite thin film according to claim 1, characterized in that: include: After the organic phase evaporation is completed, the introduction of ammonia is stopped, and nitrogen is introduced into the chamber to remove the ammonia in the equipment chamber until the ammonia in the equipment chamber is lower than a preset threshold, and then the substrate is taken out.

11. The method for preparing a perovskite thin film according to claim 1, characterized in that: include: After the organic phase evaporation is completed, the substrate is annealed to form a perovskite film. The annealing temperature of the annealing treatment is 140° C. to 170° C., and the annealing time is 10 min to 40 min.

12. A perovskite film, characterized in that: The perovskite film is prepared by the method for preparing a perovskite film according to any one of claims 1 to 11.

13. A perovskite solar cell, characterized in that: It comprises a perovskite film prepared by the method for preparing a perovskite film according to any one of claims 1 to 11.

14. The perovskite solar cell according to claim 13, characterized in that: The solar cell comprises a substrate and a hole transport layer, a perovskite film, an electron transport layer and a metal electrode which are sequentially arranged on the substrate, or, The solar cell comprises a substrate and an electron transport layer, a perovskite film, a hole transport layer and a metal electrode which are sequentially arranged on the substrate.

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