A method for passivating a perovskite thin film layer and a perovskite solar cell prepared thereby
By spin-coating a first solution and a second solution onto the perovskite thin film to form a two-dimensional perovskite passivation layer, the problem of deep and shallow energy level defects in the perovskite thin film is solved, thereby improving the photoelectric conversion efficiency and stability of perovskite solar cells.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- WUXI UTMOST LIGHT TECH CO LTD
- Filing Date
- 2022-09-27
- Publication Date
- 2026-06-12
Smart Images
Figure CN115548219B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of solar cell technology, and relates to a passivation method for a perovskite thin film layer and the perovskite solar cell prepared therefrom. Background Technology
[0002] Solar energy is a clean and inexhaustible source of energy. Utilizing solar energy is one of the most promising methods for solving humanity's energy problems, and photovoltaic cells are an effective way to directly convert solar energy into electrical energy. Currently, crystalline silicon solar cells are the most widely used on the market, but their complex manufacturing process, high-temperature processing, and high cost limit their large-scale application. Therefore, people have begun to search for new photovoltaic cells, and emerging photovoltaic devices such as dye (quantum dot) sensitized solar cells, CuInGaSe thin-film solar cells, and organic solar cells have emerged. However, the optimal photoelectric conversion efficiency of these cells is usually only half that of commercial silicon cells, and improving efficiency is extremely difficult. In recent years, perovskite solar cells (PSCs) have emerged as a dark horse, with their photoelectric conversion efficiency rapidly increasing from 3.8% in 2009 to 25.5% in 2021. Due to their simple manufacturing process, low cost, and high photovoltaic performance, they have become the most promising photovoltaic technology to replace silicon-based solar cells.
[0003] Perovskite solar cells typically consist of a fiber-to-oxide (FTO) conductive glass, an electron transport layer (ETL), a perovskite light-absorbing layer, a hole transport layer (HTM), and metal electrodes. However, in the photovoltaic field, the three key factors determining the commercial viability of solar cells are efficiency, stability, and cost. For PSCs, the low-cost solution-based fabrication process results in numerous defects in the perovskite thin film, including defects within the perovskite crystal, at grain boundaries, and on the surface. Further improvements in cell efficiency and stability urgently need to be addressed. These defects directly lead to poorer perovskite crystal quality and energy level matching between layers, increasing the probability of carrier capture and recombination, reducing charge transport efficiency, and accelerating perovskite decomposition, ultimately resulting in decreased cell efficiency and stability.
[0004] Specifically, due to the low-temperature solution process and thermal annealing involved in the fabrication of PSCs, perovskite films often generate a large number of defects and interface states. These defects seriously affect the photoelectric performance and operational stability of PSCs. In particular, most of the defects on the perovskite surface are deep-level defect states, which can cause the following adverse effects on the device: (1) Defect states can capture free charges, causing photogenerated carriers to recombine, resulting in a loss of open-circuit voltage and fill factor; (2) Charges accumulated on the surface can not only cause undesirable bending of the interface band, affecting the transport of carriers, but also cause adverse phenomena such as current and voltage hysteresis in PSCs; (3) Irregular film surface morphology can increase the leakage current of the device and reduce the short-circuit current of the battery. Even defects located inside the bulk can migrate to the surface of the perovskite under the action of an electric field, exacerbating the above adverse phenomena. In addition, the surface of the perovskite film is in contact with other functional layers (such as hole transport layer and electron transport layer) and the external environment. Chemical reactions are prone to occur at the contact interface, accelerating the degradation of the perovskite film and seriously affecting the operational stability of PSCs.
[0005] Therefore, it is desirable in this field to develop a passivation method for perovskite thin films to avoid the aforementioned defects. Summary of the Invention
[0006] To address the shortcomings of existing technologies, the present invention aims to provide a passivation method for perovskite thin films and the resulting perovskite solar cells. This invention employs a first solution and a second solution for composite passivation of the perovskite film. The first solution forms a two-dimensional perovskite layer with the surface and deeper layers of the perovskite film, improving its stability and passivating deep-level defects. The second solution, based on the two-dimensional perovskite, further fills surface vacancies and passivates shallow-level defects using a hydrophobic compound containing iodine ions, further passivating defects and improving the long-term stability of the perovskite solar cell. The method of this invention enhances the hydrophobicity of the perovskite film surface and fills iodine vacancies within the perovskite, thereby further improving the efficiency of the perovskite solar cell.
[0007] To achieve this objective, the present invention employs the following technical solution:
[0008] In a first aspect, the present invention provides a passivation method for a perovskite thin film layer, the passivation method comprising the following steps:
[0009] (1) The first solution is coated on the perovskite thin film layer and annealed to obtain a two-dimensional perovskite passivation layer.
[0010] (2) The second solution is coated on the 2D perovskite passivation layer obtained in step (1), and then annealed to obtain the second passivation layer;
[0011] The first solution includes any one or a combination of at least two of the following: phenylethyl ammonium iodide (PEAI) solution, o-fluorophenylethylamine iodide (oFPEAI) solution, n-butylamine n-butylamine iodide (BAI) solution, or butylamine iodide solution;
[0012] The second solution includes octyl iodide (OAI) solution and / or heptyl iodide solution.
[0013] This invention employs a first solution and a second solution for composite passivation of the perovskite film. The first solution can form a 2D perovskite on the surface and deeper layers of the perovskite film to improve the stability of the perovskite film and passivate deep-level defects. The second solution, based on the 2D perovskite, further fills the vacancies on the perovskite surface and passivates shallow-level defects with a hydrophobic compound containing iodine ions, thereby further passivating the defects and improving the long-term stability of the perovskite solar cell.
[0014] In this invention, a two-dimensional perovskite passivation layer is formed by spin-coating a first solution onto the perovskite thin film layer, and then a second solution is spin-coated to form a second passivation layer. The first and second solutions work together to improve the hydrophobicity of the perovskite thin film surface and fill the iodine vacancies in the perovskite, thereby achieving the effect of passivating the perovskite thin film layer and improving the efficiency of perovskite solar cells.
[0015] Preferably, the solvent in the first solution in step (1) includes isopropanol or N,N-dimethylformamide (DMF). Specifically, the solvent in the phenethyl ammonium iodide solution and the o-fluorophenylethylamine iodide solution is isopropanol, and the solvent in the n-butylamine iodide solution and the butylated diamine iodide solution is DMF.
[0016] Preferably, the coating method in step (1) includes spin coating. It should be noted that the coating in step (1) can also be one or more of the following coating methods: spraying, blade coating, etc. Preferably, the concentration of the first solution in step (1) is 0.3-0.7 mM, for example, 0.3 mM, 0.4 mM, 0.5 mM, 0.6 mM, or 0.7 mM. It should be noted that mM in this invention refers to millimoles per liter.
[0017] Preferably, in step (1), the spin-coating amount of the first solution is 30-50 μL (e.g., 30 μL, 33 μL, 35 μL, 38 μL, 40 μL, 43 μL, 45 μL, 48 μL or 50 μL, etc.) of the first solution with a concentration of 0.3-0.7 mM (e.g., 0.3 mM, 0.4 mM, 0.5 mM, 0.6 mM or 0.7 mM, etc.) spin-coating onto a perovskite film layer with an area of 1 square centimeter.
[0018] Preferably, the coating method in step (1) includes static spin coating.
[0019] Preferably, the rotation speed of the static spin coating is 3000-5000 rpm, such as 3000 rpm, 3300 rpm, 3500 rpm, 3800 rpm, 4000 rpm, 4300 rpm, 4500 rpm, 4800 rpm or 5000 rpm, and the static spin coating time is 20-40 s, such as 20 s, 23 s, 25 s, 28 s, 30 s, 33 s, 35 s, 38 s or 40 s.
[0020] Preferably, the annealing time in step (1) is 3-8 minutes, such as 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes or 8 minutes.
[0021] Preferably, the solvent in the second solution in step (2) is isopropanol.
[0022] Preferably, the coating method in step (2) includes spin coating. It should be noted that the coating in step (2) can also be one or more of the coating methods such as spraying and scraping.
[0023] Preferably, in step (2), the concentration of the second solution is 3-7 mM, such as 3 mM, 4 mM, 5 mM, 6 mM or 7 mM.
[0024] Preferably, in step (2), the amount of the second solution spin-coated is 30-50 μL (e.g., 30 μL, 33 μL, 35 μL, 38 μL, 40 μL, 43 μL, 45 μL, 48 μL or 50 μL, etc.) of the second solution with a concentration of 3-7 mM (e.g., 3 mM, 4 mM, 5 mM, 6 mM or 7 mM, etc.) spin-coated onto a 2D perovskite passivation layer with an area of 1 square centimeter.
[0025] Preferably, the coating method in step (2) includes static spin coating.
[0026] Preferably, the rotation speed of the static spin coating is 3000-5000 rpm, such as 3000 rpm, 3300 rpm, 3500 rpm, 3800 rpm, 4000 rpm, 4300 rpm, 4500 rpm, 4800 rpm or 5000 rpm, and the static spin coating time is 20-40 s, such as 20 s, 23 s, 25 s, 28 s, 30 s, 33 s, 35 s, 38 s or 40 s.
[0027] Preferably, the annealing time in step (2) is 3-8 minutes, such as 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes or 8 minutes.
[0028] It should be noted that the present invention does not impose specific limitations on the preparation method of the perovskite thin film layer in step (1), which can be prepared by conventional preparation methods in the prior art. For example, the perovskite thin film layer can be prepared by the following preparation method:
[0029] Formamidinium iodide, lead iodide, and chloromethylamine were dissolved in a mixture of dimethyl sulfoxide and dimethylformamide, and stirred to obtain a perovskite precursor solution. The perovskite precursor solution was spin-coated to obtain a perovskite precursor layer. Diethyl ether antisolvent was added dropwise to the perovskite precursor layer, and the perovskite thin film layer was obtained after annealing.
[0030] As a preferred embodiment of the present invention, the passivation method of the perovskite thin film layer includes the following steps:
[0031] (1) The first solution is dropped onto the perovskite thin film layer, statically spin-coated at a speed of 3000-5000 rpm for 20-40s, and annealed for 3-8min to obtain a 2D perovskite passivation layer.
[0032] The first solution is added by dropping 30-50 μL of a 0.3-0.7 mM solution onto a perovskite thin film layer with an area of 1 square centimeter.
[0033] (2) Add the second solution to the 2D perovskite passivation layer obtained in step (1), and statically spin coat it at a speed of 3000-5000 rpm for 20-40s, and anneal it for 3-8min to obtain the second passivation layer.
[0034] The second solution is added by dropping 30-50 μL of a 3-7 mM solution onto a 2D perovskite passivation layer with an area of 1 square centimeter.
[0035] In a second aspect, the present invention provides a perovskite solar cell, comprising a hole transport layer, a perovskite thin film layer and an electron transport layer, wherein the perovskite solar cell further comprises a two-dimensional perovskite passivation layer and a second passivation layer.
[0036] The two-dimensional perovskite passivation layer and the second passivation layer are prepared by the passivation method described in the first aspect.
[0037] Preferably, the 2D perovskite passivation layer and the second passivation layer are located between the perovskite thin film layer and the hole transport layer, and the 2D perovskite passivation layer is adjacent to the perovskite thin film layer, while the second passivation layer is adjacent to the hole transport layer.
[0038] Preferably, the perovskite solar cell further includes a mesoporous thin film layer.
[0039] It should be noted that the present invention does not specifically limit the preparation method of other layers of the perovskite solar cell. Exemplarily, the perovskite solar cell is prepared by the following method:
[0040] (1) Pre-treat FTO conductive glass with glass cleaner.
[0041] (2) Add diisopropoxydiacetylacetonate titanium to anhydrous n-butanol and add FK209Co(Ⅲ) to it. After dissolving, a mixture is obtained. Spin coat the mixture onto FTO conductive glass and dry it to form an electron transport layer.
[0042] (3) Spin-coating the solution prepared by titanium dioxide slurry and anhydrous ethanol onto the formed electron transport layer and annealing it to form a mesoporous thin film layer.
[0043] (4) Dissolve formamidinium iodide, lead iodide, and chloromethylamine in a mixture of dimethyl sulfoxide (DMSO) and dimethylformamide (DMF), and stir thoroughly to obtain a perovskite precursor solution. Then spin-coat the perovskite precursor solution onto the formed mesoporous film layer to obtain a perovskite precursor layer. Add diethyl ether antisolvent to the perovskite precursor layer and perform annealing treatment to form a perovskite film layer.
[0044] (5) The first solution was dropped onto the perovskite thin film layer, and statically spin-coated at a speed of 3000-5000 rpm for 20-40s, and annealed for 3-8min to obtain a two-dimensional perovskite passivation layer.
[0045] The first solution is added by dropping 30-50 μL of a 0.3-0.7 mM solution onto a perovskite thin film layer with an area of 1 square centimeter.
[0046] (6) Add the second solution to the 2D perovskite passivation layer obtained in step (5), and statically spin coat it at a speed of 3000-5000 rpm for 20-40s, and anneal it for 3-8min to obtain the second passivation layer.
[0047] The second solution is added by dropping 30-50 μL of a 3-7 mM solution onto a 2D perovskite passivation layer with an area of 1 square centimeter.
[0048] (7) Spin-coat the hole transport layer Spiro-OMeTAD on the second passivation layer and scrape out the FTO electrode using γ-butyrolactone (GBL).
[0049] (8) Finally, gold (Au) is deposited on the hole transport layer substrate using a vacuum evaporation device to form a metal electrode, thereby obtaining the perovskite solar cell.
[0050] Compared with the prior art, the present invention has the following beneficial effects:
[0051] In this invention, a two-dimensional perovskite passivation layer is formed by spin-coating a first solution onto the perovskite thin film layer, and then a second solution is spin-coated to form a second passivation layer. The first and second solutions work synergistically to improve the hydrophobicity of the perovskite thin film surface and fill the iodine vacancies within the perovskite, thereby achieving the effects of passivating the perovskite thin film layer and improving the efficiency of perovskite solar cells (photoelectric conversion efficiency: 17.04%-22.12%). Attached Figure Description
[0052] Figure 1 This is a schematic diagram of the structure of the perovskite solar cell provided in Example 1;
[0053] Among them, 1-FTO conductive glass, 2-electron transport layer, 3-mesoporous thin film layer, 4-perovskite thin film layer, 5-2D perovskite passivation layer, 6-second passivation layer, 7-hole transport layer, and 8-metal electrode. Detailed Implementation
[0054] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.
[0055] Example 1
[0056] This embodiment provides a passivation method for a perovskite thin film layer and a perovskite solar cell. The passivation method and the fabrication method of the perovskite solar cell include the following steps:
[0057] (1) Pre-treat FTO conductive glass with glass cleaner.
[0058] (2) Add diisopropoxydiacetylacetone titanium to anhydrous n-butanol, and add FK209Co(Ⅲ) (the molar ratio of FK209Co(Ⅲ) to diisopropoxydiacetylacetone titanium is 1:500)). After thorough shaking and dissolution, a mixture is obtained. The mixture is spin-coated onto FTO conductive glass and dried to form an electron transport layer (thickness of 30nm).
[0059] (3) Spin-coating a solution of titanium dioxide slurry and anhydrous ethanol in a mass ratio of 1:8 onto the formed electron transport layer and then annealing it to form a mesoporous thin film layer (thickness of 80 nm).
[0060] (4) Dissolve formamidinium iodide, lead iodide and chloromethylamine in a molar ratio of 4:4:1 in a mixture of dimethyl sulfoxide and dimethylformamide in a volume ratio of 1:4, and stir thoroughly to obtain a perovskite precursor solution. Then spin-coat the perovskite precursor solution onto the formed mesoporous film layer to obtain a perovskite precursor layer. Add diethyl ether antisolvent to the perovskite precursor layer and anneal it to form a perovskite film layer (thickness of 450 nm).
[0061] (5) Add phenylethyl ammonium iodide solution to the perovskite thin film layer, and statically spin coat it at 4000 rpm for 30 s on a spin coater, and anneal for 5 min to obtain a 2D perovskite passivation layer.
[0062] The amount of phenylethyl ammonium iodide solution added was 40 μL of 0.5 mM phenylethyl ammonium iodide solution added to a perovskite film layer with an area of 1 square centimeter.
[0063] (6) Add octyl iodide solution to the 2D perovskite passivation layer obtained in step (5), and statically spin coat it at a speed of 4000 rpm for 30 seconds on a spin coater, and anneal it for 5 minutes to obtain the second passivation layer.
[0064] The amount of octyl iodide solution added was 40 μL of 5 mM octyl iodide solution added to a 2D perovskite passivation layer with an area of 1 square centimeter.
[0065] (7) A hole transport layer Spiro-OMeTAD (100 nm thick) was spin-coated on the second passivation layer, and an FTO electrode was scraped out using GBL.
[0066] (8) Finally, Au is deposited on the hole transport layer substrate using a vacuum evaporation device to form a metal electrode, thereby obtaining the perovskite solar cell.
[0067] The structural schematic diagram of the perovskite solar cell provided in this embodiment is as follows: Figure 1 As shown.
[0068] Example 2
[0069] The only difference between this embodiment and embodiment 1 is that steps (5) and (6) are different from those in embodiment 1. Steps (5) and (6) specifically include the following steps:
[0070] (5) Add phenylethyl ammonium iodide solution to the perovskite thin film layer, and statically spin coat it at 3000 rpm for 40 s on a spin coater, and anneal for 3 min to obtain a 2D perovskite passivation layer.
[0071] The amount of phenylethyl ammonium iodide solution added was 30 μL of 0.3 mM phenylethyl ammonium iodide solution added to a perovskite film layer with an area of 1 square centimeter.
[0072] (6) Add octyl iodide solution to the 2D perovskite passivation layer obtained in step (5), and statically spin coat it at 3000 rpm for 40 seconds on a spin coater, and anneal it for 3 minutes to obtain the second passivation layer.
[0073] The amount of octyl iodide solution added was 30 μL of 3 mM octyl iodide solution added to a 2D perovskite passivation layer with an area of 1 square centimeter.
[0074] Example 3
[0075] The only difference between this embodiment and embodiment 1 is that steps (5) and (6) are different from those in embodiment 1. Steps (5) and (6) specifically include the following steps:
[0076] (5) Add phenylethyl ammonium iodide solution to the perovskite thin film layer, and statically spin coat it at 5000 rpm for 20s on a spin coater, and anneal it for 8min to obtain a 2D perovskite passivation layer.
[0077] The amount of phenylethyl ammonium iodide solution added was 50 μL of 0.7 mM phenylethyl ammonium iodide solution added to a perovskite film layer with an area of 1 square centimeter.
[0078] (6) Add octyl iodide solution to the 2D perovskite passivation layer obtained in step (5), and statically spin coat it at a speed of 5000 rpm for 20 seconds on a spin coater, and anneal it for 8 minutes to obtain the second passivation layer.
[0079] The amount of octyl iodide solution added was 50 μL of 7 mM octyl iodide solution added to a 2D perovskite passivation layer with an area of 1 square centimeter.
[0080] Example 4
[0081] The only difference between this embodiment and Embodiment 1 is that the octyl iodide solution in step (6) is replaced with a heptayl iodide solution.
[0082] Example 5
[0083] The only difference between this embodiment and Example 1 is that the phenylethyl ammonium iodide solution in step (5) is replaced with o-fluorophenylethylamine iodide solution.
[0084] Example 6
[0085] The only difference between this embodiment and Embodiment 1 is that the phenylethyl ammonium iodide solution in step (5) is replaced with o-fluorophenylethylamine iodide solution, and the octylamine iodide solution in step (6) is replaced with heptylamine iodide solution.
[0086] Example 7
[0087] The only difference between this embodiment and Example 1 is that the phenylethyl ammonium iodide solution in step (5) is replaced with n-butylamine iodide solution.
[0088] Example 8
[0089] The only difference between this embodiment and Embodiment 1 is that the phenylethyl ammonium iodide solution in step (5) is replaced with n-butylamine iodide solution, and the octylamine iodide solution in step (6) is replaced with heptylamine iodide solution.
[0090] Example 9
[0091] The only difference between this embodiment and embodiment 1 is that step (5) is different from that in embodiment 1. Step (5) specifically includes the following steps:
[0092] (5) Add phenylethyl ammonium iodide solution to the perovskite thin film layer, and statically spin coat it at 5000 rpm for 20s on a spin coater, and anneal it for 8min to obtain a 2D perovskite passivation layer.
[0093] The amount of phenylethyl ammonium iodide solution added was 50 μL of 1 mM phenylethyl ammonium iodide solution added to a perovskite film layer with an area of 1 square centimeter.
[0094] Example 10
[0095] The only difference between this embodiment and embodiment 1 is that step (6) is different from that in embodiment 1. Step (6) specifically includes the following steps:
[0096] (6) Add octyl iodide solution to the 2D perovskite passivation layer obtained in step (5), and statically spin coat it at a speed of 5000 rpm for 20 seconds on a spin coater, and anneal it for 8 minutes to obtain the second passivation layer.
[0097] The amount of octyl iodide solution added was 50 μL of 10 mM octyl iodide solution added to a 2D perovskite passivation layer with an area of 1 square centimeter.
[0098] Comparative Example 1
[0099] The only difference between this comparative example and Example 1 is that it does not include steps (5) and (6), that is, the hole transport layer Spiro-OMeTAD is directly spin-coated on the perovskite thin film without passivating the perovskite thin film.
[0100] Comparative Example 2
[0101] The only difference between this comparative example and Example 1 is that step (6) is not included, that is, the perovskite solar cell prepared has only one passivation layer (phenylethyl ammonium iodide passivation layer).
[0102] Comparative Example 3
[0103] The only difference between this comparative example and Example 1 is that step (5) is not included, that is, the perovskite solar cell prepared has only one passivation layer (octyl iodide passivation layer).
[0104] On the IV test instrument, perovskite solar cells provided in the 0.1 square centimeter example and the comparative example were tested based on a standard solar light intensity. The IV test started with an on-state voltage of 1.1V, ended with an on-state voltage of -0.1V, scan steps of 0.02V, and a delay time of 50 milliseconds.
[0105] The performance test results are shown in Table 1.
[0106] Table 1
[0107] Voc(V) <![CDATA[Jsc(mA / cm 2 )]]> FF (%) PCE (%) Example 1 1.06 26.56 78.19 22.12 Example 2 1.04 26.21 78.01 21.26 Example 3 1.05 26.30 77.95 21.53 Example 4 0.94 24.88 72.58 17.04 Example 5 1.06 25.30 77.53 20.84 Example 6 1.02 25.19 78.81 20.03 Example 7 0.98 26.03 75.45 19.00 Example 8 1.08 25.40 73.21 20.27 Example 9 1.05 26.40 78.15 21.67 Example 10 1.06 26.50 78.50 22.06 Comparative Example 1 0.99 25.14 75.10 18.85 Comparative Example 2 1.05 26.52 69.75 19.58 Comparative Example 3 1.01 25.37 78.15 19.97
[0108] Wherein, Voc is the open-circuit voltage; Jsc is the short-circuit current density; FF is the fill factor; and PCE is the photoelectric conversion efficiency.
[0109] As can be seen from Table 1, the perovskite solar cells provided in the embodiments of the present invention all have high photoelectric conversion efficiencies (17.04%-22.12%).
[0110] Compared to Example 1, the photoelectric conversion efficiency of the perovskite solar cell provided in Comparative Example 1 decreased significantly, and the photoelectric conversion efficiency of the perovskite solar cells provided in Comparative Examples 2-3 decreased significantly.
[0111] The applicant declares that this invention illustrates the passivation method of the perovskite thin film layer and the prepared perovskite solar cell through the above embodiments, but this invention is not limited to the above embodiments, that is, it does not mean that this invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials used in this invention, additions of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.
Claims
1. A passivation method for a perovskite thin film layer, characterized in that, The passivation method includes the following steps: (1) The first solution is coated on the perovskite thin film layer and annealed to obtain a two-dimensional perovskite passivation layer; (2) The second solution is coated on the 2D perovskite passivation layer obtained in step (1), and then annealed to obtain the second passivation layer; The first solution includes any one or a combination of at least two of the following: phenylethyl ammonium iodide solution, o-fluorophenylethylamine iodide solution, n-butylamine iodide solution, or butylated diamine iodide solution; The second solution includes octyl iodide solution and / or heptyl iodide solution.
2. The passivation method according to claim 1, characterized in that, Step (1) The solvent in the first solution includes isopropanol or N,N-dimethylformamide.
3. The passivation method according to claim 1, characterized in that, The coating method described in step (1) includes spin coating.
4. The passivation method according to claim 1, characterized in that, Step (1) The concentration of the first solution is 0.3-0.7 mM.
5. The passivation method according to claim 1, characterized in that, Step (1) The spin-coating amount of the first solution is 30-50 μL of the first solution with a concentration of 0.3-0.7 mM spin-coated onto a perovskite thin film layer with an area of 1 square centimeter.
6. The passivation method according to claim 1, characterized in that, The coating method described in step (1) includes static spin coating.
7. The passivation method according to claim 6, characterized in that, The rotation speed of the static spin coating is 3000-5000 rpm, and the static spin coating time is 20-40 s.
8. The passivation method according to claim 1, characterized in that, The annealing time in step (1) is 3-8 min.
9. The passivation method according to claim 1, characterized in that, In step (2), the solvent in the second solution is isopropanol.
10. The passivation method according to claim 1, characterized in that, The coating method described in step (2) includes spin coating.
11. The passivation method according to claim 1, characterized in that, In step (2), the concentration of the second solution is 3-7 mM.
12. The passivation method according to claim 1, characterized in that, Step (2) The amount of the second solution spin-coated is 30-50 μL of the second solution with a concentration of 3-7 mM spin-coated onto a 2D perovskite passivation layer with an area of 1 square centimeter.
13. The passivation method according to claim 1, characterized in that, The coating method described in step (2) includes static spin coating.
14. The passivation method according to claim 13, characterized in that, The rotation speed of the static spin coating is 3000-5000 rpm, and the static spin coating time is 20-40 s.
15. The passivation method according to claim 1, characterized in that, The annealing time in step (2) is 3-8 min.
16. The passivation method according to claim 1, characterized in that, The perovskite thin film layer was prepared by the following method: Iodoformin, lead iodide, and chloromethylamine were dissolved in a mixture of dimethyl sulfoxide and dimethylformamide, and the mixture was stirred to obtain a perovskite precursor solution. The perovskite precursor solution is spin-coated to obtain a perovskite precursor layer; diethyl ether antisolvent is added dropwise to the perovskite precursor layer, and after annealing, the perovskite thin film layer is obtained.
17. A perovskite solar cell, comprising a hole transport layer, a perovskite thin film layer, and an electron transport layer, characterized in that, The perovskite solar cell also includes a 2D perovskite passivation layer and a second passivation layer. The two-dimensional perovskite passivation layer and the second passivation layer are prepared by the passivation method according to any one of claims 1-16.
18. The perovskite solar cell according to claim 17, characterized in that, The 2D perovskite passivation layer and the second passivation layer are located between the perovskite thin film layer and the hole transport layer, with the 2D perovskite passivation layer adjacent to the perovskite thin film layer and the second passivation layer adjacent to the hole transport layer.
19. The perovskite solar cell according to claim 18, characterized in that, The perovskite solar cell further includes a mesoporous thin film layer, which is located between the electron transport layer and the perovskite thin film layer.