Perovskite solar cell, preparation method thereof and perovskite photovoltaic module comprising same

Abstract

The application provides a perovskite solar cell, a preparation method thereof and a perovskite photovoltaic module comprising the same, the perovskite solar cell comprising an electrically conductive substrate, a perovskite layer, an interface encapsulation layer and a metal electrode layer, the interface encapsulation layer being arranged adjacent to the metal electrode layer; the material of the interface encapsulation layer comprises a functional group capable of forming an anchoring effect with the metal electrode, including any one or a combination of at least two of a mercaptan group, a phosphine group, an amine group, an amide group or a cyano group. In the perovskite solar cell provided by the application, the material of the interface encapsulation layer comprises a functional group capable of forming an anchoring effect with the metal electrode, and the material of the interface encapsulation layer can also interact with lead ions, can effectively block the migration of iodine ions and the metal electrode to avoid their direct contact and reaction, and can also prevent lead from leaking to the external environment, thereby significantly improving the stability and safety of the perovskite photovoltaic module.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solar cells, and relates to a perovskite solar cell, a preparation method thereof and a perovskite photovoltaic module comprising the same. BACKGROUND

[0002] As a new type of thin-film photovoltaic technology that has attracted much attention in recent years, perovskite solar cells have become a research hotspot in the current photovoltaic industry and research teams in colleges and universities due to their high power conversion efficiency, low cost and low-temperature printing preparation. With the rapid development of nanotechnology and material science, the semiconductor properties and physical and chemical properties of perovskite materials have been gradually revealed, which provides a theoretical basis and technical support for the development of perovskite photovoltaic technology. However, the commercialization process of perovskite photovoltaic modules still faces the huge obstacle of insufficient operational stability. This problem mainly comes from two aspects. First, the internal factor is the lattice degradation reaction caused by ion migration in the perovskite composition: in actual use, the organic cations (CH3NH3 + , CH(NH2) 2+ )) and halide ions (I - ) in the perovskite thin film can easily induce spontaneous ion migration, which leads to the decomposition of hydrogen iodide (HI) and iodine (I2). These decomposition products can further react with common metal electrode materials (such as aluminum (Al), silver (Ag), copper (Cu), etc.) to form compounds such as AlI3, AgI, CuI2, etc. According to the principle of chemical equilibrium, the presence of corresponding by-products can accelerate the layer-by-layer degradation of perovskite crystals during the aging process of the battery, directly leading to permanent reduction of battery efficiency. The second external factor mainly includes humidity, oxygen, temperature and light, which may be encountered during battery operation: first, the invasion of water into the perovskite photovoltaic module can cause the hydrolysis process of the perovskite thin film, leading to its decomposition and performance degradation, and the influence mechanism is shown in the following reaction formulas ① and ②; second, oxygen can accelerate the oxidative decomposition of perovskite materials, especially when the temperature is high or in a strong light environment, the presence of oxygen can accelerate the degradation rate of the perovskite layer, and the specific influence process is shown in the following reaction formulas ③ and ④; finally, temperature fluctuations, whether the temperature rises or falls, can affect the crystalline quality and stability of perovskite materials, thereby negatively affecting the photoelectric conversion efficiency of the battery.

[0003]

[0004] O2+e - =O2 - ③

[0005] 4CH3NH3PbI3+O2 -→ 4PbI2+ 2I2+ 2H2O + 4CH3NH2 ④

[0006] Therefore, in order to meet the working stability standards of commercial certification requirements, it is necessary to reasonably design the packaging of perovskite photovoltaic modules. In this regard, based on the barrier interface design of perovskite materials, the packaging process of crystalline silicon photovoltaic modules with relatively mature technology can be used for reference. In crystalline silicon solar cells, the cell sheet is usually connected with the back plate and glass through a hot melt adhesive film, which can not only isolate water and oxygen, but also provide rigid support. The service life of the packaged module can reach more than 25 years.

[0007] The existing module packaging technology generally adopts the following steps: first, selecting suitable packaging materials, including cover plate materials (polyethylene terephthalate composite film (PET), polyimide composite film (PI), flexible glass polyvinyl butyral film (PVB), etc.), edge sealing glue (butyl glue, epoxy resin, polyurethane glue, polybutadiene oligomer, acrylic resin glue, etc.), inner adhesive (polyolefin adhesive film (POE), acrylic resin glue, epoxy resin glue, polyurethane glue, etc.). Then use the inner adhesive of appropriate size to cover the top of the cell, and use the edge sealing glue at the edge of the cell to ensure that the active area of the cell is isolated from the external environment. Finally, using appropriate process (such as hot pressing, ultraviolet (UV) curing, etc.) to firmly fix the cover plate material on the cell, ensuring that the adhesion strength between the cover plate material and the cell is sufficient to ensure the integrity and stability of the packaging. This packaging method is widely used in the packaging of various modules. However, this method can only isolate the influence of the external environment on the perovskite photovoltaic module, and the internal factors affecting the stability of the perovskite photovoltaic module have not been solved.

[0008] Therefore, in the field, it is desirable to develop a perovskite solar cell that can solve the problem of insufficient intrinsic stability of perovskite materials in perovskite photovoltaic modules. SUMMARY

[0009] In view of the deficiencies of the prior art, the purpose of the present application is to provide a perovskite solar cell, a preparation method thereof and a perovskite photovoltaic module comprising the same. The present application provides a perovskite solar cell that optimizes the hygrothermal stability and lead leakage phenomenon of perovskite photovoltaic modules. By introducing an interface packaging material with excellent barrier properties, ion migration in the perovskite thin film can be significantly inhibited, and the leakage of lead ions can be effectively suppressed, thereby improving the safety and stability of the perovskite photovoltaic module.

[0010] To achieve the purpose of the present application, the following technical solutions are adopted:

[0011] In a first aspect, the present application provides a perovskite solar cell, comprising an electrically conductive substrate, a perovskite layer, an interface encapsulation layer, and a metal electrode layer, wherein the interface encapsulation layer is disposed adjacent to the metal electrode layer.

[0012] The material of the interface encapsulation layer comprises a functional group capable of forming an anchoring effect with the metal electrode, including any one or a combination of at least two of a thiol group (-SH), a phosphine group (-PR2), an amine group (-NH2), an amide group (-CONH2), or a cyano group (-CN). These functional groups have atoms capable of providing lone pair electrons or having strong electronegativity, thereby forming coordination bonds or similar chemical bonds with the metal center.

[0013] The perovskite solar cell provided by the present application has the material of the interface encapsulation layer comprising a functional group capable of forming an anchoring effect with the metal electrode (such as Ag, etc.), and the material of the interface encapsulation layer can also interact with lead ions (Pb 2+ ), effectively blocking the migration of iodine ions and metal electrodes to avoid their direct contact and reaction, while also preventing lead (Pb) from leaking to the external environment, thereby significantly improving the stability and safety of the perovskite photovoltaic module.

[0014] Studies have shown that the main factors affecting the internal stability of the perovskite photovoltaic module are the migration of iodine ions (I - ) and Ag in the perovskite film. Under normal circumstances, this is a reversible ion migration process. However, once the migrated ions (I - ) react with the metal electrode, this reversible process is broken, causing irreversible layer-by-layer degradation of the perovskite film, and also causing reverse corrosion of the metal electrode. By introducing an interface encapsulation layer comprising a functional group capable of forming an anchoring effect with the metal electrode, the present application can effectively reduce ion migration in the perovskite, inhibit lead leakage, and the interface encapsulation layer material is closely combined with the top metal electrode, which can weaken the direct reaction of the metal electrode-iodine ions in the perovskite, significantly improving the safety and stability of the perovskite photovoltaic module.

[0015] Preferably, the material of the interface encapsulation layer comprises any one or a combination of at least two of 2-mercaptoethanol, tricyclohexylphosphine, triphenylphosphine, dithiothreitol, ethanethiol, ethylenediamine, triethylamine, bis(benzaldehyde) diimine nickel bis(triphenylphosphine), triisopropylphosphine, pentafluorophenyl diphenyl phosphate, tributylphosphine, tricyanomethane, and dicyanomethane.

[0016] Preferably, the thickness of the interface encapsulation layer is 10-20 nm, such as 10 nm, 12 nm, 14 nm, 16 nm, 18 nm, 20 nm, etc.

[0017] Preferably, the perovskite solar cell further comprises any one or a combination of at least two of a hole transport layer, an electron transport layer, a buffer layer.

[0018] Preferably, the perovskite solar cell comprises, in sequence, an electrically conductive substrate, a hole transport layer, a perovskite layer, an electron transport layer, a buffer layer, an interface encapsulation layer, and a metal electrode layer.

[0019] Preferably, the electrically conductive substrate comprises an indium tin oxide (ITO) conductive film polyethylene naphthalate (PEN).

[0020] Preferably, the material of the metal electrode layer comprises any one of aluminum, silver, and copper.

[0021] It should be noted that the material of the hole transport layer, the perovskite layer, the electron transport layer, and the buffer layer is not specifically limited, and can be a material commonly used in the prior art. For example, the material of the hole transport layer can be [4-(3, 6-dimethoxy-9H-carbazole-9-yl) butyl] phosphonic acid (MEO-4PACZ) and / or (2-(3, 6-dimethoxy-9H-carbazole-9-yl) ethyl) phosphonic acid (MEO-2PACZ); the perovskite layer can be prepared using methylamine bromide, methylamine iodide, methylamine chloride, cesium iodide, lead iodide, lead bromide, etc. as raw materials, and a mixture of sulfone solvents and amide solvents as solvents; the material of the electron transport layer can be C60, etc.; and the material of the buffer layer can be 2, 9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline (BCP), etc.

[0022] Preferably, the thickness of the hole transport layer is 20-100 nm, such as 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, etc.

[0023] Preferably, the thickness of the perovskite layer is 300-700 nm, such as 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, etc.

[0024] Preferably, the thickness of the electron transport layer is 20-100 nm, such as 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm, 85 nm, 90 nm, 95 nm, 100 nm, etc.

[0025] Preferably, the thickness of the buffer layer is 5-50 nm, such as 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, etc.

[0026] In a second aspect, the present application provides a method for preparing the perovskite solar cell according to the first aspect, the method comprising the following steps:

[0027] (1) providing an electrically conductive substrate;

[0028] (2) forming a hole transport layer on the electrically conductive substrate;

[0029] (3) forming a perovskite layer on the hole transport layer;

[0030] (4) forming an electron transport layer on the perovskite layer;

[0031] (5) forming a buffer layer on the electron transport layer;

[0032] (6) mixing a material of an interface encapsulation layer and a solvent, stirring to obtain an interface encapsulation layer precursor solution, and coating the interface encapsulation layer precursor solution on the buffer layer by a slot coating method to form an interface encapsulation layer;

[0033] (7) forming a metal electrode layer on the interface encapsulation layer to obtain the perovskite solar cell.

[0034] Preferably, the solvent in step (6) comprises any one or a combination of at least two of 2,2,2-trifluoroethanol, tetrahydrofuran, and 2,2,2-trifluoroethyl methyl ether.

[0035] Preferably, in step (6), the amount of the material of the interface encapsulation layer is 0.5-2 mg, for example 0.5 mg, 0.6 mg, 0.8 mg, 1 mg, 1.2 mg, 1.4 mg, 1.6 mg, 1.8 mg, 2 mg, or the like, based on the amount of the solvent of 1 mL.

[0036] Preferably, the solution is kept at room temperature during the stirring in step (6).

[0037] Preferably, the stirring in step (6) is until the material of the interface encapsulation layer is completely dissolved.

[0038] Preferably, in the slot coating in step (6), the gap between the slot coating head and the substrate is controlled to be 50-100 μm, for example 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, or the like, and the speed is controlled to be 8-12 mm / s, for example 8 mm / s, 8.5 mm / s, 9 mm / s, 9.5 mm / s, 10 mm / s, 10.5 mm / s, 11 mm / s, 11.5 mm / s, 12 mm / s, or the like.

[0039] The present invention does not specifically limit the preparation raw materials, specific steps, and parameters involved in steps (1) to (5) and (7) of the method for preparing a perovskite solar cell. The method can be prepared by referring to conventional steps in the prior art. For example, the method for preparing a perovskite solar cell of the present invention includes the following steps:

[0040] (1) Tear off the protective films on both sides of the ITO conductive film PEN, put it into the laser etcher for etching, and set aside.

[0041] (2) Immersing the ITO conductive film PEN substrate obtained in step (1) in a SAM solution to prepare a hole transport layer with a thickness of 20-100 nm (e.g., 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, etc.), wherein the SAM solution is a mixed solution of MEO-4PACZ or MEO-2PACZ and ethanol.

[0042] (3) The mass and definition of the drugs methylamine bromide, iodomethane, methylamine chloride, cesium iodide, lead iodide, and lead bromide are 100%, wherein methylamine bromide is 0.1% to 2% (e.g., 0.1%, 0.3%, 0.5%, 1%, 1.5%, 2%, etc.), iodomethane is 10% to 30% (e.g., 10%, 15%, 20%, 25%, 30%, etc.), methylamine chloride is 0.5% to 5% (e.g., 0.5%, 1%, 1.5%, 2%, 2. 5%, 3%, 3.5%, 4%, 4.5%, 5%, etc.), lead iodide is 50% to 80% (for example, 50%, 55%, 60%, 65%, 70%, 75%, 80%, etc.), lead bromide is 1% to 5% (for example, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, etc.), and cesium iodide is the balance; the solvent is a first solvent (dimethyl sulfoxide or N-methylpyrrolidone) and a second solvent ( A mixture of an amide solvent, such as N,N-dimethylformamide, etc., wherein the second solvent is 70% to 90% (e.g., 70%, 75%, 80%, 85%, 90%, etc.) and the first solvent is 10% to 30% (e.g., 10%, 15%, 20%, 25%, 30%, etc.), and the above-mentioned drugs and solvents are mixed and stirred at 60-80°C (e.g., 60°C, 65°C, 70°C, 75°C, 80°C, etc.). A perovskite precursor solution is prepared in 10-15 hours (for example, 10 hours, 12 hours, 14 hours, 15 hours, etc.) for use, and the perovskite precursor solution is slit-coated on the surface of the hole transport layer obtained in step (2) to prepare a perovskite layer with a thickness of 300-700 nm (for example, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, etc.).

[0043] (4) The perovskite layer surface obtained in step (3) is prepared into an electron transport layer by evaporating C60 in a manner of evaporation, with a thickness of 20-100 nm (for example, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm, 85 nm, 90 nm, 95 nm, 100 nm, etc.), and is etched in a laser etching machine.

[0044] (5) The C60 surface obtained in step (4) is prepared into a buffer layer by evaporating BCP in a manner of evaporation, with a thickness of 5-50 nm (for example, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, etc.).

[0045] (6) The interface encapsulation layer material is added into a solvent and stirred, and the solution is kept at room temperature during the stirring process. The prepared solution is continuously stirred at room temperature for 20-30 hours (for example, 20 hours, 22 hours, 24 hours, 26 hours, 28 hours, 30 hours, etc.), to obtain an interface encapsulation layer precursor solution that can be used for slot coating. An interface encapsulation layer is prepared on the BCP buffer layer surface obtained in step (5) by using a slot coating method, with a gap between the slot coating head and the substrate fixed at 50-100 μm (for example, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, etc.), and the printing is performed at a speed fixed at 8-12 mm / s (for example, 8 mm / s, 8.5 mm / s, 9 mm / s, 9.5 mm / s, 10 mm / s, 10.5 mm / s, 11 mm / s, 11.5 mm / s, 12 mm / s, etc.).

[0046] (7) The interface encapsulation layer surface obtained in step (6) is evaporated with a metal electrode, and is etched in a laser etching machine.

[0047] In a third aspect, the present application provides a perovskite photovoltaic module, which comprises the perovskite solar cell according to the first aspect.

[0048] Preferably, the perovskite photovoltaic module is a flexible module with an area of 100 cm 2 .

[0049] Compared with the prior art, the present application has the following beneficial effects:

[0050] The perovskite solar cell provided by the present application comprises an interface encapsulation layer, the material of the interface encapsulation layer comprises a functional group capable of forming an anchoring effect with a metal electrode (for example, Ag, etc.), and the material of the interface encapsulation layer can also form an anchoring effect with lead ions (Pb2+ )produce interaction, can effectively block the migration of iodine ions and metal electrode to avoid their direct contact reaction, while also preventing lead (Pb) to the external environment leakage, thereby significantly improving the stability and safety of perovskite photovoltaic components. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 Structure diagram of perovskite solar cell provided for Example 1;

[0052] 1-ITO conductive film PEN, 2-hole transport layer, 3-perovskite layer, 4-electron transport layer, 5-buffer layer, 6-interfacial encapsulation layer, 7-metal electrode layer.

[0053] Figure 2 Comparison diagram of normalized absorption intensity test results of perovskite solar cells provided for Example 1 and Comparative Example 1.

[0054] Figure 3 The curve of lead concentration in water over time after the perovskite solar cells provided for Example 1 and Comparative Example 1 are placed in water.

[0055] Figure 4 The curve of the ratio of photoelectric conversion efficiency of perovskite solar cells provided for Example 1 and Comparative Example 1 in a 50% relative humidity air environment over time. DETAILED DESCRIPTION

[0056] The technical solutions of the present application will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only to help understand the present application and should not be regarded as specific limitations on the present application.

[0057] Example 1

[0058] In this embodiment, a perovskite solar cell is provided, and a structure diagram thereof is shown as Figure 1 The perovskite solar cell includes a conductive substrate (ITO conductive film PEN) 1, a hole transport layer 2, a perovskite layer 3, an electron transport layer 4, a buffer layer 5, an interfacial encapsulation layer 6, and a metal electrode layer 7, which are sequentially stacked.

[0059] The preparation method includes the following steps:

[0060] (1) The protective film on both sides of the ITO conductive film PEN is torn off and placed in a laser etching machine for etching, ready for use.

[0061] (2) The ITO conductive film PEN substrate obtained in step (1) is immersed in a SAM solution to prepare a hole transport layer with a thickness of 50 nm, and the SAM solution is a mixed solution of MEO-4PACZ and ethanol (wherein the concentration of MEO-4PACZ in the mixed solution is 0.5 mmol / L).

[0062] (3) The mass of the medicines bromomethylamine, iodomethylamide, chloromethylamine, cesium iodide, lead iodide, and lead bromide is defined as 100%, wherein the mass of bromomethylamine is 1%, the mass of iodomethylamide is 20%, the mass of chloromethylamine is 3%, the mass of lead iodide is 65%, the mass of lead bromide is 3%, and the mass of cesium iodide is the remainder; the solvent is a mixture of a first solvent (dimethyl sulfoxide) and a second solvent (an amide solvent, N,N-dimethylformamide), wherein the volume percentage of the second solvent is 80%, and the volume percentage of the first solvent is 20%, and the above medicines and the solvent are mixed and continuously stirred at 70°C for 12 hours to prepare a perovskite precursor solution (wherein the concentration of the medicines in the perovskite precursor solution is 1.1 mol / L) for standby, and the perovskite precursor solution is slot-coated on the surface of the hole transport layer obtained in step (2) to prepare a perovskite layer with a thickness of 500 nm.

[0063] (4) C60 is evaporated on the surface of the perovskite layer obtained in step (3) by evaporation to prepare an electron transport layer with a thickness of 30 nm, and the electron transport layer is etched in a laser etching machine.

[0064] (5) BCP is evaporated on the surface of the C60 obtained in step (4) by evaporation to prepare a buffer layer with a thickness of 10 nm.

[0065] (6) 1 mg of interface encapsulation layer material (2-mercaptoethanol) is added to 1 mL of solvent (2,2,2-trifluoroethanol) and stirred, and the solution is kept at room temperature during the stirring process. The prepared solution is continuously stirred at room temperature for 24 hours to obtain an interface encapsulation layer precursor solution that can be used for slot coating, and the interface encapsulation layer is prepared on the surface of the BCP buffer layer obtained in step (5) by slot coating, the gap between the slot coating head and the substrate is fixed at 80 μm, and the printing speed is fixed at 10 mm / s to prepare the interface encapsulation layer, and the thickness of the prepared interface encapsulation layer is 15 nm.

[0066] (7) A metal electrode (Ag) is evaporated on the surface of the interface encapsulation layer obtained in step (6) to obtain a metal electrode layer with a thickness of 100 nm, and the metal electrode layer is etched in a laser etching machine.

[0067] Example 2

[0068] The difference between this example and Example 1 is that in step (6), the interface encapsulation layer material (2-mercaptoethanol) is replaced by an equal mass of tricyclohexylphosphine.

[0069] Example 3

[0070] The difference between this embodiment and embodiment 1 is only that in step (6), the interfacial encapsulation layer material (2-mercaptoethanol) is replaced by an equal mass of tributylphosphine.

[0071] Embodiment 4

[0072] The difference between this embodiment and embodiment 1 is only that in step (6), the amount of interfacial encapsulation layer material (2-mercaptoethanol) is 0.5 mg, and the thickness of the prepared interfacial encapsulation layer is 10 nm.

[0073] Embodiment 5

[0074] The difference between this embodiment and embodiment 1 is only that in step (6), the amount of interfacial encapsulation layer material (2-mercaptoethanol) is 2 mg, and the thickness of the prepared interfacial encapsulation layer is 20 nm.

[0075] Comparative Example 1

[0076] The difference between this comparative example and embodiment 1 is only that the provided perovskite solar cell does not include an interfacial encapsulation layer, and accordingly, the preparation method does not include step (6), and the metal electrode is evaporated on the buffer layer to form a metal electrode layer.

[0077] Comparative Example 2

[0078] The difference between this comparative example and embodiment 1 is only that in step (6), the interfacial encapsulation layer material (2-mercaptoethanol) is replaced by an equal mass of cyclohexanol.

[0079] The comparative graph of the normalized absorption intensity test results of the perovskite solar cells provided by embodiment 1 and comparative example 1 is shown in Figure 2 It can be seen that compared with the perovskite solar cell of comparative example 1 which does not include an interfacial encapsulation layer, the light absorption intensity of the perovskite solar cell provided by embodiment 1 has been improved to a certain extent, which is conducive to improving the efficiency of the perovskite photovoltaic module.

[0080] The perovskite solar cells provided by embodiment 1 and comparative example 1 are directly placed in water, and the concentration of lead in the water is determined by flame atomic absorption spectrometry (FAAS), and the test results are shown in Figure 3 It can be seen that as the time increases, the lead concentration of the perovskite solar cell without an interfacial encapsulation layer (comparative example 1) rapidly increases, and after the interfacial encapsulation layer is added (embodiment 1), the lead concentration hardly increases, and the lead leakage is obviously inhibited.

[0081] The perovskite solar cells provided by embodiment 1 and comparative example 1 are placed in a 50% relative humidity air environment, and the change of the photoelectric conversion efficiency ratio of the battery with time is tested, and the test result graph is shown in Figure 4As shown, the solar cell without the interface encapsulation layer (Comparative Example 1) has an efficiency of less than 40% of the initial value after 30 days, and the solar cell with the interface encapsulation layer (Example 1) has an efficiency decrease of less than 5% after 180 days, which shows that the safety and stability of the perovskite solar cell are improved after the interface encapsulation layer is added.

[0082] The perovskite solar cells provided by the examples and the comparative examples of the present application were stored in an air environment with a relative humidity of 50%, and the photoelectric conversion efficiency (PCE) test results in the initial state and after a period of storage are shown in Table 1.

[0083] Table 1

[0084]

[0085] As shown in Table 1, compared with the comparative examples, the perovskite solar cells provided by the examples of the present application have higher stability in an air environment with a relative humidity of 50%.

[0086] The perovskite solar cells provided by the examples and the comparative examples of the present application were stored in a nitrogen atmosphere, and the photoelectric conversion efficiency (PCE) test results in the initial state and after a period of storage are shown in Table 2.

[0087] Table 2

[0088]

[0089] As shown in Table 2, compared with the comparative examples, the perovskite solar cells provided by the examples of the present application also have higher stability in a nitrogen atmosphere.

[0090] In summary, by using the interface encapsulation strategy in the perovskite photovoltaic module, the present application introduces an encapsulation layer with blocking properties. This layer not only effectively prevents ion migration and leakage of lead ions in the perovskite thin film, but also strengthens the bonding between electrodes by forming an anchoring effect with the top metal electrode (such as silver), thereby significantly enhancing the stability of the entire cell. This method provides an effective solution for improving the safety and long-term reliability of perovskite photovoltaic modules. After the perovskite solar cell is placed in an air environment with a relative humidity of 50% for 180 days, the efficiency of the module obtained by the interface encapsulation strategy changes by no more than 5%, and after external encapsulation, the safety and stability of the perovskite photovoltaic module are further improved, which has great significance for preparing safe and stable perovskite photovoltaic modules.

[0091] The applicant declares that the perovskite solar cell, the preparation method thereof and the perovskite photovoltaic module comprising the same of the present application are illustrated by the above-mentioned embodiments, but the present application is not limited to the above-mentioned embodiments, i.e. it does not mean that the present application must rely on the above-mentioned embodiments to be implemented. It should be understood by those skilled in the art that any improvement of the present application, equivalent replacement of the raw materials selected by the present application, addition of auxiliary ingredients, selection of specific modes, etc. fall within the protection scope and disclosure scope of the present application.

Claims

1. A perovskite solar cell, characterized in that The perovskite solar cell comprises a conductive substrate, a perovskite layer, an interface encapsulation layer and a metal electrode layer, wherein the interface encapsulation layer is located between the metal electrode layer and the perovskite layer and is disposed adjacent to the metal electrode layer; The material of the interface encapsulation layer is any one of 2-mercaptoethanol, dithiothreitol, ethanethiol, ethylenediamine, triethylamine, tricyanomethane, and dicyanomethane, or a combination of at least two of them.

2. The perovskite solar cell according to claim 1, characterized in that The thickness of the interface encapsulation layer is 10-20 nm.

3. The perovskite solar cell according to claim 1, wherein The perovskite solar cell further includes any one of a hole transport layer, an electron transport layer, and a buffer layer, or a combination of at least two of them.

4. The perovskite solar cell according to claim 1, wherein The perovskite solar cell includes a conductive substrate, a hole transport layer, a perovskite layer, an electron transport layer, a buffer layer, an interface encapsulation layer, and a metal electrode layer which are stacked in sequence.

5. The perovskite solar cell according to claim 1, wherein The conductive substrate includes an indium tin oxide conductive film polyethylene naphthalate.

6. The perovskite solar cell according to claim 5, characterized in that The material of the metal electrode layer includes any one of aluminum, silver and copper.

7. A method for preparing a perovskite solar cell according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: (1) Providing a conductive substrate; (2) forming a hole transport layer on the conductive substrate; (3) forming a perovskite layer on the hole transport layer; (4) forming an electron transport layer on the perovskite layer; (5) forming a buffer layer on the electron transport layer; (6) mixing the material of the interface encapsulation layer and the solvent, stirring, and obtaining an interface encapsulation layer precursor solution, and coating the interface encapsulation layer precursor solution on the buffer layer by a slit coating method to form an interface encapsulation layer; (7) Forming a metal electrode layer on the interface encapsulation layer to obtain the perovskite solar cell.

8. The preparation method according to claim 7, characterized in that The solvent in step (6) includes any one of 2,2,2-trifluoroethanol, tetrahydrofuran, and 2,2,2-trifluoroethyl methyl ether, or a combination of at least two thereof.

9. The preparation method according to claim 7, characterized in that In step (6), based on the amount of solvent used being 1 mL, the amount of the material of the interface encapsulation layer used is 0.5-2 mg.

10. The preparation method according to claim 7, characterized in that The stirring in step (6) is carried out until the material of the interface encapsulation layer is completely dissolved.

11. The preparation method according to claim 7, characterized in that During the slit coating process in step (6), the gap between the slit coating head and the substrate is controlled to be 50-100 μm, and the speed is 8-12 mm / s.

12. A perovskite photovoltaic module, characterized in that: The perovskite photovoltaic module includes the perovskite solar cell according to any one of claims 1 to 6.

13. The perovskite photovoltaic module according to claim 12, characterized in that: The perovskite photovoltaic module is a flexible module.

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