Solar cell and preparation method and application thereof

Abstract

The invention discloses a solar cell and a preparation method and application thereof. The solar cell comprises a substrate, a hole transport layer, a perovskite light absorption layer, an electron transport layer and an electrode which are stacked. The material of the perovskite light absorption layer comprises a perovskite base material and a perovskite material passivator in a mass ratio of (1.4-1.8): (0.5-1.5), and the perovskite material passivator comprises a compound with the following general formula; wherein R1 is sulfonic acid group or-[SO3]-M < + >, M < + > is Cs < + >, Rb < + >, NH4 < + >, [CH3NH3] < + >, [HC (NH2) 2] < + > or 1 / 2Sn < 2 + >, R4 is hydrazino, amino or formamidino, and R2, R3, R5 and R6 are respectively and independently selected from H, nitryl or halogen. By adding the perovskite material passivator, the perovskite base material is effectively anchored, double-point synergistic passivation is realized, and the performance of the solar cell is improved.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and in particular to a solar cell, its preparation method, and its application. Background Technology

[0002] Perovskite solar cells use perovskite material as the light-absorbing layer and are characterized by high efficiency and low cost. Their structure typically includes electrodes, an electron transport layer, a perovskite layer, and a hole transport layer. Electron-hole pairs are generated by absorbing light, separated by the transport layer, and collected by the electrodes to form an electric current. Their efficiency has improved rapidly in recent years, making them a hot research topic in the photovoltaic field.

[0003] However, the presence of multiple defects such as cation vacancies in perovskite materials can lead to severe nonradiative recombination. Furthermore, the pH fluctuations and stoichiometric imbalances caused by the hydrolysis of perovskite precursors such as methyl iodide (MAI) significantly reduce the passivation effect, exacerbating crystallization defects and film quality degradation. These problems collectively restrict the improvement of perovskite solar cell device performance. Summary of the Invention

[0004] Based on this, in order to improve the performance of solar cells, this application provides a solar cell, its preparation method, and its application.

[0005] This application provides a solar cell, including a stacked substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and electrodes;

[0006] The substrate is either a conductive substrate or a battery substrate.

[0007] The perovskite light-absorbing layer comprises a perovskite base material in a mass ratio of (1.4~1.8):(0.5~1.5) and a perovskite material passivating agent, wherein the perovskite material passivating agent comprises compounds having the following general formula.

[0008] ;

[0009] Wherein, R1 is a sulfonic acid group or -[SO3]. - M + M + For Cs + 、Rb + NH4 + [CH3NH3] + [HC(NH2)2] + or 1 / 2Sn 2+ R4 is hydrazine, amino, or formamidinium, and R2, R3, R5, and R6 are each independently selected from H, nitro, or halogen.

[0010] In one embodiment, R1 in the perovskite material passivating agent is a sulfonic acid group.

[0011] In one embodiment, the perovskite material passivator includes at least one of the following materials:

[0012] , , , , , as well as .

[0013] In one embodiment, the perovskite-based material has the chemical formula ABX3, wherein A includes NH4. + [CH3NH3] + [CH3CH2NH3] + [(CH3)2NH2] + [(CH3)3NH] + [(CH3)4N] + [HC(NH2)2] + [CH3C(NH2)2] + [H3C2(NH2)2] + Cs + 、Rb + Li + 、Tl + K + Na + And [C(NH2)3] + One or more of the following; B includes Pb 2+ Sn 2+ and Ge 2+ One or more of them; X includes I - ,Br - Cl - SCN - BF4 - and BF6 - One or more of them.

[0014] In one embodiment, the substrate is a battery substrate, which includes crystalline silicon solar cells, copper indium gallium selenide thin-film solar cells, cadmium telluride thin-film solar cells, III-V group thin-film solar cells, or perovskite solar cells.

[0015] This application also provides a method for preparing a solar cell, comprising the following steps:

[0016] A hole transport layer is formed on a substrate, wherein the substrate is a conductive substrate or a battery substrate;

[0017] A perovskite precursor solution is formed on the surface of the hole transport layer away from the substrate, and then annealed to prepare the perovskite light-absorbing layer. The perovskite precursor solution comprises the perovskite base material, the perovskite passivating agent, and a solvent in a ratio of (1.4~1.8) mg:(0.5~1.5) mg:1 mL. The perovskite precursor solution also comprises the perovskite base material, the perovskite passivating agent, and a solvent in a ratio of (1.4~1.8) mg:(0.5~1.5) mg:1 mL. The perovskite passivating agent comprises a compound having the following general formula.

[0018] ;

[0019] Wherein, R1 is a sulfonic acid group or -[SO3]. - M + M + For Cs + 、Rb + NH4 + [CH3NH3] + [HC(NH2)2] + or 1 / 2Sn 2+ R4 is hydrazine, amino, or formamidinium, and R2, R3, R5, and R6 are each independently selected from H, nitro, or halogen.

[0020] An electron transport layer and electrodes are formed on the perovskite light-absorbing layer.

[0021] In one embodiment, the annealing time is 10 min to 20 min.

[0022] In one embodiment, the annealing temperature is 100°C to 150°C.

[0023] In one embodiment, the method for forming the perovskite precursor solution includes spin coating, blade coating, slot coating, spray pyrolysis, or inkjet printing.

[0024] This application provides a photovoltaic module, including the solar cell described above.

[0025] This application provides a power supply device for an electrical device, including the solar cell described above or a solar cell prepared according to the preparation method described above, such as a photovoltaic module described above.

[0026] This application provides a perovskite material passivator added to the perovskite light-absorbing layer of a solar cell. The perovskite material passivator has sulfonic acid groups and amino or formamidinium groups at the para position of the benzene ring backbone. The spacing between the sulfonic acid groups and the amino / formamidinium groups can be controlled to be 0.7-0.9 nm. Other polar reinforcing groups are introduced at other positions of the benzene ring, which can effectively anchor the perovskite material and achieve dual-site synergistic passivation, thereby effectively improving the performance of the solar cell. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer and to provide a more thorough and comprehensive understanding of the disclosure of this application, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments. The described embodiments are only a part of the embodiments of this application, and not all of them.

[0028] The implementation of this application is described in detail below. This embodiment is implemented based on the technical solution of this application, and provides detailed implementation methods and specific operation processes, but the protection scope of this application is not limited to the following embodiment.

[0029] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application and in its specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0030] Unless otherwise stated or in case of conflict, the terms or phrases used in this application shall have the following meanings:

[0031] In this application, the terms "multiple" or "various" are used unless otherwise specified, referring to a quantity greater than or equal to 2. For example, "at least one" or "at least one" means one or more than two.

[0032] In this application, terms such as "further" and "especially" are used to describe purposes and indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0033] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0034] In this application, when numerical intervals (i.e., numerical ranges) are mentioned, unless otherwise specified, the distribution of selectable numerical values ​​within the numerical interval is considered continuous, and includes the two endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. The term "numerical interval" can be broadly included to include numerical interval types such as percentage intervals, ratio intervals, and proportion intervals.

[0035] In this application, unless otherwise specified, temperature parameters are permitted to be either isothermal or vary within a certain temperature range. It should be understood that isothermal treatment allows temperature fluctuations within the precision range of the instrument control. Fluctuations are permitted within ranges such as ±5℃, ±4℃, ±3℃, ±2℃, and ±1℃.

[0036] Unless otherwise specified, the percentage content mentioned in this application refers to mass percentage for solid-liquid mixtures and solid-phase-solid mixtures, and volume percentage for liquid-phase-liquid mixtures.

[0037] In this application, the temperature parameter, unless otherwise specified, is allowed to be either constant temperature treatment or treatment within a certain temperature range. Constant temperature treatment allows temperature fluctuations within the precision range controlled by the instrument. The room temperature in this application refers to 0-40℃, preferably 10℃-35℃, and more preferably 20℃-30℃.

[0038] This application provides a solar cell, including a stacked substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and electrodes;

[0039] The substrate is either a conductive substrate or a battery substrate.

[0040] The perovskite light-absorbing layer comprises a perovskite base material in a mass ratio of (1.4~1.8):(0.5~1.5) and a perovskite passivating agent. The perovskite passivating agent comprises compounds having the following general formula.

[0041] ;

[0042] Wherein, R1 is a sulfonic acid group or -[SO3]. - M + M + For Cs +、Rb + NH4 + [CH3NH3] + [HC(NH2)2] + or 1 / 2Sn 2+ R4 is hydrazine, amino, or formamidinium, and R2, R3, R5, and R6 are each independently selected from H, nitro, or halogen.

[0043] This application provides a perovskite material passivator added to the perovskite light-absorbing layer of a solar cell. The perovskite material passivator has sulfonic acid groups and amino or formamidinium groups at the para position of the benzene ring backbone. The spacing between the sulfonic acid groups and the amino / formamidinium groups can be controlled to be 0.7-0.9 nm. Other polar reinforcing groups are introduced at other positions of the benzene ring, which can effectively anchor the perovskite material and achieve dual-site synergistic passivation, thereby effectively improving the performance of the solar cell.

[0044] In a specific example, R1 is a sulfonic acid group.

[0045] In one specific example, the perovskite material passivator includes at least one of the following materials:

[0046] 4-Formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid 4-Amino-3,5-dichlorobenzenesulfonic acid 4-Amino-3,5-dinitrobenzenesulfonic acid 4-Methylamidinyl-2,3,5,6-Tetrafluorobenzenesulfonic acid 4-Methylamidinyl-2,6-difluoro-3,5-nitrobenzenesulfonic acid 4-Hydroxy-3,5-dichlorobenzenesulfonic acid and 4-methylamino-3,5-nitrobenzenesulfonic acid .

[0047] In a specific example, the chemical formula of the perovskite-based material is ABX3, where the A-site cation is typically a monovalent cation, including at least one of a monovalent metal cation and a monovalent organic cation, wherein the monovalent metal cation is selected from cesium ions (Cs). + ), rubidium ions (Rb + Lithium ion (Li) + Sodium ions (Na) + ), potassium ions (K) + ) and thallium ions (Tl + One or more of the following, wherein the monovalent organic cation is selected from ammonium ions (NH4+). + ), Methylamine ion (MA) (CH3NH3) + ), ethylammonium ion (CH3CH2NH3) + ), dimethylamine ion ((CH3)2NH2)+ ), trimethylammonium ion ((CH3)3NH + ), tetramethylammonium ion ((CH3)4N + ), formamidinium ion (FA) (HC(NH2)2) + ), Methylformamidinium ion (CH3C(NH2)2 + Acetamidinium ion (H3C2(NH2)2) + ) and guanidine ions (C(NH2)3 + One or more of the following. The B-site cation is usually a divalent metal cation, selected from lead ions (Pb). 2+ ), tin ions (Sn) 2+ ) and germanium ions (Ge 2+ One or more of the following. The X-position anion includes halide anions, such as bromide ions (Br₂). - ), iodide ions (I - ), chloride ions (Cl) - ), thiocyanate ions (SCN) - ), tetrafluoroborate ion (BF4) - ) and hexafluoroborate ions (BF6) - One or more of the following.

[0048] In a specific example, the substrate is a battery substrate, which includes crystalline silicon solar cells, copper indium gallium selenide thin-film solar cells, cadmium telluride thin-film solar cells, III-V group thin-film solar cells, or perovskite solar cells.

[0049] Furthermore, the substrate is a conductive substrate, which may be, but is not limited to, one or more of ITO, IZO, IWO, FTO, ICO, and AZO. The conductive substrate is prepared by, but is not limited to, one or two of magnetron sputtering (PVD) and reactive plasma deposition (RPD). The thickness of the conductive substrate is 20 nm to 100 nm. Specifically, the thickness of the conductive substrate may be, but is not limited to, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, or 100 nm.

[0050] Furthermore, the solar cell is a flexible solar cell, and the substrate material can be, but is not limited to, an organic polymer or a metal. Specifically, the organic polymer can be, but is not limited to, one or more of polyimide (PI), polyester (PET), and polyethylene naphthalate (PEN).

[0051] Understandably, the materials for the hole transport layer include one or more of transition metal oxides, self-assembled monolayer materials, and polymers. Transition metal oxides include one or both of nickel oxide (NiO) and copper oxide (CuO). Polymers may be, but are not limited to, poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS). Self-assembled monolayer materials generally consist of anchoring groups, linking groups, and terminal groups, and can form a monolayer on the substrate surface through self-assembly, thereby playing a role in regulating interfacial properties, promoting charge transport, and reducing nonradiative recombination. Self-assembled monolayer materials may include, but are not limited to, [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (2PACz), [2-(3,6-diphenyl-9H-carbazole-9-yl)ethyl]phosphonic acid (Me-2PACz), (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid (MeO-2PACz), and 2-(3,6-dibromo-9H-carbazole-9-yl)ethyl]phosphonic acid (Br-2PACz). 2-(3,6-dichloro-9H-carbazole-9-yl)ethyl]phosphonic acid (Cl-2PACz), 2-(3,6-difluoro-9H-carbazole-9-yl)ethyl]phosphonic acid (F-2PACz), [4-(9H-carbazole-9-yl)ethyl]phosphonic acid (4PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz), [4-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl ... [4-(3,6-dibromo-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), [4-(3,6-dibromo-9H-carbazole-9-yl)butyl]phosphonic acid (Br-4PACz), (4-(3,6-dichloro-9H-carbazole-9-yl)butyl)phosphonic acid (Cl-4PACz), (4-(3,6-difluoro-9H-carbazole-9-yl)butyl)phosphonic acid (F-4PACz), [4-(7H-dibenzocarbazole-7-yl)butyl]phosphonic acid (4PAD) One of the following: CB), [4-(2,7-dibromo-9,9-dimethylacridin-10(9-hydro)-yl)butyl]phosphonic acid (2Br-4DMAcPA), sodium 4-phenylbutyrate (4-PBA), (2-(4-(bis(4-methoxyphenyl)amino)phenyl)-1-cyanovinyl)phosphonic acid (MPA-CPA), and [2-(3,7-dibromo-10H-phenthiazin-10-yl)ethyl]phosphonic acid (Br-2EPT).

[0052] Furthermore, the material of the electron transport layer may be, but is not limited to, one or more of fullerene (C60) and its derivatives, tin oxide (SnO2), zinc oxide (ZnO), and magnesium oxide (MgO).

[0053] Furthermore, the fullerene derivative can be, but is not limited to, methyl (6,6)-phenyl-C61-butyrate (PCBM). The thickness of the electron transport layer is 3 nm to 50 nm. Further, the electrode can be, but is not limited to, a metallic electrode. The electrode material includes one or more of copper (Cu), aluminum (Al), silver (Ag), nickel (Ni), cobalt (Co), gold (Au), molybdenum (Mo), and chromium (Cr). The electrode fabrication method includes, but is not limited to, one or more of physical vapor deposition, screen printing, electroplating, and inkjet printing. The electrode thickness is 100 nm to 20 μm.

[0054] In a specific example, the substrate is a battery substrate, which includes crystalline silicon solar cells, copper indium gallium selenide thin-film solar cells, cadmium telluride thin-film solar cells, III-V group thin-film solar cells, or perovskite solar cells.

[0055] This application also provides a method for preparing a solar cell, comprising the following steps:

[0056] A hole transport layer is formed on a substrate, which is a conductive substrate or a battery substrate.

[0057] A perovskite precursor solution is formed on the surface of the hole transport layer away from the substrate, and then annealed to prepare a perovskite light-absorbing layer. The perovskite precursor solution comprises a perovskite base material, a perovskite passivating agent, and a solvent in a ratio of (1.4~1.8) mg:(0.5~1.5) mg:1 mL. The perovskite passivating agent comprises a perovskite base material, a perovskite passivating agent, and a solvent in a ratio of (1.4~1.8) mg:(0.5~1.5) mg:1 mL. The perovskite passivating agent comprises compounds having the following general formula.

[0058] ;

[0059] Wherein, R1 is a sulfonic acid group or -[SO3]. - M + M + For Cs + 、Rb + NH4 + [CH3NH3] + [HC(NH2)2] + or 1 / 2Sn 2+ R4 is hydrazine, amino, or formamidinium, and R2, R3, R5, and R6 are each independently selected from H, nitro, or halogen.

[0060] An electron transport layer and electrodes are formed on the perovskite light-absorbing layer.

[0061] In one specific example, the solvent includes one or both of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Further, the solvent includes N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of (2–6):1. Understandably, the solvent ratio may include 2:1, 3:1, 4:1, 5:1, or 6:1.

[0062] In a specific example, the annealing time is 10 to 20 minutes; the annealing temperature is 100°C to 150°C. Specifically, the annealing time can be, but is not limited to, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 minutes. The annealing temperature can be, but is not limited to, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, or 150°C.

[0063] In a specific example, methods for forming a perovskite precursor solution on a substrate include spin coating, blade coating, slot coating, spray pyrolysis, or inkjet printing.

[0064] Furthermore, this application provides a photovoltaic module, including the solar cell as described above.

[0065] Furthermore, this application provides an electrical device whose power supply device includes a solar cell as described above.

[0066] In one specific example, the battery may include an outer packaging. This outer packaging can be used to encapsulate the aforementioned electrode components and electrolyte. In one specific example, the battery's outer packaging can be a rigid shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The battery's outer packaging can also be a soft pack, such as a pouch. The soft pack can be made of plastic; further, non-limiting examples of plastics may include one or more of polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0067] In a specific example, the electrical device can be a mobile phone, laptop, smartwatch, electric vehicle, medical device, portable charging station, aerospace equipment, smart home, or energy storage power station. The energy storage power station can be a photovoltaic energy storage power station, a wind power energy storage power station, a hydropower energy storage power station, a thermal power energy storage power station, etc.

[0068] Unless otherwise specified, all raw materials used in the following examples are commercially available products.

[0069] Example 1

[0070] This embodiment provides a solar cell, the fabrication steps of which are as follows:

[0071] Cleaning the ITO transparent conductive substrate: Place a 1×1cm 2 The ITO transparent conductive substrate was ultrasonically cleaned sequentially by immersion in ethanol, detergent, ultrapure water, isopropanol, and ethanol. The cleaned ITO glass substrate was then dried with nitrogen gas. The volume of solvent used for ultrasonic cleaning was 500 mL, and each ultrasonic cleaning session lasted 15 minutes. The ITO transparent conductive substrate includes a glass substrate and an indium tin oxide transparent conductive layer formed on the surface of the glass substrate.

[0072] Preparation of hole transport layer: SAM material is mixed with anhydrous ethanol and stirred at room temperature in a glove box under nitrogen atmosphere until completely dissolved to obtain hole transport layer solution. The solution is spin-coated onto the indium tin oxide transparent conductive layer on the surface of the glass substrate and annealed to form hole transport layer.

[0073] Preparation of the perovskite layer: In a glove box under a nitrogen atmosphere, the perovskite base material and the perovskite passivator 4-amino-3,5-dichlorobenzenesulfonic acid were dissolved in a mixed solvent of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) (volume ratio 4:1). The mixture was stirred at room temperature until completely dissolved to obtain a perovskite precursor solution. The concentration of the perovskite base material in the perovskite precursor solution was 1.4 mg / mL, and the concentration of the perovskite passivator in the perovskite precursor solution was 0.5 mg / mL.

[0074] In a glove box under a nitrogen atmosphere, a perovskite precursor solution was spin-coated onto an ITO transparent conductive substrate with a hole transport layer, and then extracted with an antisolvent. The substrate was then placed on a hot stage and annealed at 120°C for 10 minutes to form a perovskite layer.

[0075] Preparation of electron transport layer: The ITO transparent conductive substrate with perovskite layer is transferred to a vacuum coating instrument, and a C60 layer is deposited on the perovskite layer; then, tin dioxide (SnO2) is prepared on the C60 layer by atomic layer deposition to obtain electron transport layer.

[0076] Preparation of silver electrode: The ITO transparent conductive substrate with an electron transport layer is transferred to a vacuum coating instrument, and a silver electrode is deposited by evaporation to obtain a single-junction perovskite cell.

[0077] Example 2

[0078] This embodiment provides a solar cell. Compared to Embodiment 1, the perovskite material passivator 4-amino-3,5-dichlorobenzenesulfonic acid is replaced with 4-hydrazino-3,5-dichlorobenzenesulfonic acid, and the concentration of the perovskite base material in the perovskite precursor solution is 1.6 mg / mL, the concentration of the perovskite material passivator in the perovskite precursor solution is 0.5 mg / mL, and other operations are the same as in Embodiment 1.

[0079] Example 3

[0080] This embodiment provides a solar cell. Compared to Embodiment 1, the perovskite material passivator 4-amino-3,5-dichlorobenzenesulfonic acid is replaced with 4-amino-3,5-dinitrobenzenesulfonic acid, and the concentration of the perovskite base material in the perovskite precursor solution is 1.4 mg / mL, the concentration of the perovskite material passivator in the perovskite precursor solution is 0.8 mg / mL, and other operations are the same as in Embodiment 1.

[0081] Example 4

[0082] This embodiment provides a solar cell. Compared to Embodiment 1, the perovskite material passivator 4-amino-3,5-dichlorobenzenesulfonic acid is replaced with 4-formamidinyl-2,3,5,6-tetrafluorobenzenesulfonic acid, and the concentration of the perovskite base material in the perovskite precursor solution is 1.5 mg / mL, the concentration of the perovskite material passivator in the perovskite precursor solution is 0.9 mg / mL, and other operations are the same as in Embodiment 1.

[0083] Example 5

[0084] This embodiment provides a solar cell. Compared to Embodiment 1, the perovskite material passivator 4-amino-3,5-dichlorobenzenesulfonic acid is replaced with 4-formamidinyl-2,6-difluoro-3,5-nitrobenzenesulfonic acid, and the concentration of the perovskite base material in the perovskite precursor solution is 1.4 mg / mL, the concentration of the perovskite material passivator in the perovskite precursor solution is 1.0 mg / mL, and other operations are the same as in Embodiment 1.

[0085] Example 6

[0086] This embodiment provides a solar cell. Compared to Embodiment 1, the perovskite material passivator 4-amino-3,5-dichlorobenzenesulfonic acid is replaced with 4-formamidinyl-3,5-nitrobenzenesulfonic acid, and the concentration of the perovskite base material in the perovskite precursor solution is 1.5 mg / mL, while the concentration of the perovskite material passivator in the perovskite precursor solution is 0.6 mg / mL. Other operations are the same as in Embodiment 1.

[0087] Comparative Example 1

[0088] Compared to Example 1, Comparative Example 1 eliminated the use of 4-amino-3,5-dichlorobenzenesulfonic acid, the perovskite material passivator, in the perovskite precursor material. Instead, the perovskite precursor material was directly dissolved in a mixed solvent of DMF and DMSO and stirred until completely dissolved to obtain a perovskite precursor solution. Other operations were the same as in Example 1.

[0089] The perovskite material passivator in Examples 1 to 6 above was applied to the perovskite layer of a single-junction perovskite solar cell. Comparative Example 1 did not apply the perovskite material passivator to the perovskite layer and is a conventional single-junction perovskite solar cell.

[0090] A single-junction perovskite solar cell was prepared in Comparative Example 1. The efficiency of the single-junction perovskite solar cells obtained in Examples 1 to 6 and Comparative Example 1 was tested. The test results are shown in Table 1 below.

[0091] Table 1

[0092]

[0093] As shown in the table above, the efficiency of the single-junction perovskite solar cells obtained in Examples 1 to 6 is significantly improved compared to that of the single-junction perovskite solar cell obtained in Comparative Example 1. This indicates that doping the perovskite material with the passivating agent can regulate grain growth and effectively passivate defects at the grain interface, thereby improving the cell efficiency.

[0094] The methods for preparing single-junction perovskite solar cells provided in Examples 1 to 5 above have strong industrial compatibility, employing a low-temperature process (≤110℃) and are suitable for large-area coating (average efficiency of ≥22.5% for 11.1cm² modules), reducing raw material costs by over 92%. The application of the technical solutions of this application in perovskite / crystalline silicon tandem solar cells will be described below with reference to examples.

[0095] Example 7

[0096] This embodiment provides a solar cell, the fabrication steps of which are as follows:

[0097] Crystalline silicon substrate: Provides a crystalline silicon substrate, which includes an N-type monocrystalline silicon substrate, a P-type amorphous silicon thin film deposited on the front side of the N-type monocrystalline silicon substrate and a silver electrode, and an N-type amorphous silicon thin film deposited on the back side of the N-type monocrystalline silicon substrate.

[0098] Ethanol was spin-coated in a spin coater to clean the N-type amorphous silicon thin film on the back of the bottom cell. This process was repeated twice, followed by heat treatment at 200°C to complete the cleaning.

[0099] Preparation of hole transport layer: SAM material was mixed with anhydrous ethanol and stirred at room temperature in a glove box under nitrogen atmosphere until completely dissolved to obtain SAM precursor solution. The SAM precursor solution was spin-coated onto a crystalline silicon bottom cell. Then it was placed on a hot stage at 100°C and heated and annealed for 10 min to form hole transport layer.

[0100] Preparation of the perovskite layer: In a glove box under a nitrogen atmosphere, the perovskite base material and the perovskite passivator 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid were dissolved in a mixed solvent of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) (volume ratio 4:1). The mixture was stirred at room temperature until completely dissolved to obtain a perovskite precursor solution. The concentration of the perovskite base material in the perovskite precursor solution was 1.6 mg / mL, and the concentration of the perovskite passivator in the perovskite precursor solution was 0.9 mg / mL.

[0101] In a glove box under a nitrogen atmosphere, a perovskite precursor solution is spin-coated onto an ITO transparent conductive substrate with a hole transport layer, extracted with an antisolvent, and then heated and annealed on a hot stage to form a perovskite layer.

[0102] Preparation of electron transport layer: A C60 layer is deposited on the perovskite layer; then, a tin dioxide (SnO2) layer is prepared on the C60 layer using atomic layer deposition. C60 and SnO2 mainly play the role of electron transport, forming an electron transport layer.

[0103] Preparation of transparent conductive layer: At room temperature, indium zinc oxide (IZO) thin film is deposited on the surface of electron transport layer by DC magnetron sputtering. The sputtering power is controlled at 400W and sputtering is carried out for 120s to obtain transparent conductive layer.

[0104] Preparation of silver electrode: Using a vacuum deposition instrument, a silver electrode is deposited on a transparent conductive layer, and then an anti-reflection layer is vacuum deposited on the surface of the silver electrode to complete the preparation of the perovskite top cell and obtain a perovskite / crystalline silicon tandem cell.

[0105] Example 8

[0106] This embodiment provides a solar cell. Compared to Embodiment 7, the perovskite material passivator 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid is replaced with 4-amino-3,5-dichlorobenzenesulfonic acid, and the concentration of the perovskite base material in the perovskite precursor solution is 1.8 mg / mL, the concentration of the perovskite material passivator in the perovskite precursor solution is 1.0 mg / mL, and other operations are the same as in Embodiment 7.

[0107] Example 9

[0108] This embodiment provides a solar cell. Compared to Embodiment 7, the perovskite material passivator 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid is replaced with 4-amino-3,5-dinitrobenzenesulfonic acid, and the concentration of the perovskite base material in the perovskite precursor solution is 1.7 mg / mL, the concentration of the perovskite material passivator in the perovskite precursor solution is 1.5 mg / mL, and other operations are the same as in Embodiment 7.

[0109] Comparative Example 2

[0110] Compared to Example 7, Comparative Example 2 eliminated the use of 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid, the perovskite material passivating agent, in the perovskite precursor material. Instead, the perovskite base material was directly dissolved in a mixed solvent of DMF and DMSO and stirred until completely dissolved to obtain a perovskite precursor solution. Other operations were the same as in Example 7.

[0111] Comparative Example 3

[0112] Compared to Example 7, Comparative Example 3 replaced the perovskite material passivator 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid with benzenesulfonic acid in the perovskite precursor material, while other operations were the same as in Example 7.

[0113] Comparative Example 4

[0114] Compared to Example 7, Comparative Example 4 replaced the perovskite material passivator 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid with 3,5-diamino-4-chlorobenzenesulfonic acid in the perovskite precursor material, while other operations were the same as in Example 7.

[0115] Comparative Example 5

[0116] Compared to Example 7, Comparative Example 5 replaced the perovskite material passivator 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid with 3-amino-4-chlorobenzenesulfonic acid in the perovskite precursor material, while other operations were the same as in Example 7.

[0117] Comparative Example 6

[0118] Compared to Example 7, Comparative Example 6 replaced the perovskite material passivator 4-formamidin-2,6-dichloro-3,5-nitrobenzenesulfonic acid with 4-(2-aminoethyl)benzenesulfonic acid in the perovskite precursor material, while other operations were the same as in Example 7.

[0119] The efficiency of the perovskite / crystalline silicon tandem solar cells obtained in Examples 7 to 9 and Comparative Examples 2 to 6 was tested, and the test results are shown in Table 2 below.

[0120] Table 2

[0121]

[0122] As shown in the table above, the average efficiency of the perovskite / crystalline silicon tandem solar cells obtained in Examples 7 to 9 is above 32.5%, which is a significant improvement compared to the perovskite / crystalline silicon tandem solar cell obtained in Comparative Example 2. This indicates that doping the perovskite with the passivating agent can regulate grain growth and effectively passivate defects at the grain interface, thereby improving the cell efficiency.

[0123] In summary, Examples 1 to 6, by applying perovskite material passivators to the perovskite layer, resulted in perovskite single-junction solar cells with significantly improved efficiency compared to the single-junction perovskite solar cell obtained in Comparative Example 1, exhibiting substantial improvements in both open-circuit voltage and fill factor. This demonstrates that precisely locking the spacing between bifunctional groups to 0.7–0.9 nm using a rigid benzene ring framework perfectly matches the perovskite surface defect distribution (0.6–0.8 nm spacing between uncoordinated Pb²⁺ and A-site vacancies), successfully achieving perovskite crystallization regulation and synergistic passivation effects at both sites.

[0124] The single-junction perovskite solar cells obtained in Examples 1 to 6 above showed an average increase in grain size of approximately 100-150 nm, with an average AFM roughness of only 0.3 nm. This demonstrates that the application of passivating agents in perovskite materials can eliminate pinholes and significantly improve grain spacing. Furthermore, the perovskite precursor solution's storage life was extended from 7 days to 20 days while still maintaining the expected efficiency. The turn-on voltage reached 1.28V, the fill factor reached 84.79%, and the single-junction device efficiency exceeded 23.04%. The efficiency remained >99% after 1000 hours of operation at high temperature (85°C) and >95% of the initial efficiency after 2400 hours in a humid and hot environment (85%RH).

[0125] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0126] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A solar cell, characterized in that, It includes a stacked substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and electrodes; The substrate is either a conductive substrate or a battery substrate. The perovskite light-absorbing layer comprises a perovskite base material in a mass ratio of (1.4~1.8):(0.5~1.5) and a perovskite material passivating agent, wherein the perovskite material passivating agent comprises compounds having the following general formula. ； Wherein, R1 is a sulfonic acid group or -[SO3]. - M + M + For Cs + 、Rb + NH4 + [CH3NH3] + [HC(NH2)2] + or 1 / 2Sn 2+ R4 is hydrazine, amino, or formamidinium, and R2, R3, R5, and R6 are each independently selected from H, nitro, or halogen.

2. The solar cell as described in claim 1, characterized in that, In the perovskite material passivating agent, R1 is a sulfonic acid group.

3. The solar cell as described in claim 1 or 2, characterized in that, The perovskite material passivating agent includes at least one of the following materials: , , , , , as well as .

4. The solar cell as described in claim 1 or 2, characterized in that, The chemical formula of the perovskite-based material is ABX3, where A includes NH4+. + [CH3NH3] + [CH3CH2NH3] + [(CH3)2NH2] + [(CH3)3NH] + [(CH3)4N] + [HC(NH2)2] + [CH3C(NH2)2] + [H3C2(NH2)2] + Cs + 、Rb + Li + 、Tl + K + Na + And [C(NH2)3] + One or more of the following; B includes Pb 2+ Sn 2+ and Ge 2+ One or more of them; X includes I - ,Br - Cl - SCN - BF4 - and BF6 - One or more of them.

5. The solar cell as described in claim 1 or 2, characterized in that, The substrate is a battery substrate, which includes crystalline silicon solar cells, copper indium gallium selenide thin-film solar cells, cadmium telluride thin-film solar cells, III-V group thin-film solar cells, or perovskite solar cells.

6. A method for preparing a solar cell, characterized in that, Includes the following steps: A hole transport layer is formed on a substrate, wherein the substrate is a conductive substrate or a battery substrate; A perovskite precursor solution is formed on the surface of the hole transport layer away from the substrate, and then annealed to prepare the perovskite light-absorbing layer. The perovskite precursor solution comprises the perovskite base material, the perovskite material passivating agent, and a solvent in a ratio of (1.4~1.8) mg:(0.5~1.5) mg:1 mL. The perovskite material passivating agent comprises a compound having the following general formula. ； Wherein, R1 is a sulfonic acid group or -[SO3]. - M + M + For Cs + 、Rb + NH4 + [CH3NH3] + [HC(NH2)2] + or 1 / 2Sn 2+ R4 is hydrazine, amino, or formamidinium, and R2, R3, R5, and R6 are each independently selected from H, nitro, or halogen. An electron transport layer and electrodes are formed on the perovskite light-absorbing layer.

7. The method for preparing a solar cell as described in claim 6, characterized in that, Annealing meets one or two of the following conditions: (1) The annealing time is 10 min to 20 min; (2) The annealing temperature is 100°C~150°C.

8. The method for preparing a solar cell according to any one of claims 6 to 7, characterized in that, Methods for forming the perovskite precursor solution include spin coating, blade coating, slot coating, spray pyrolysis, or inkjet printing.

9. A photovoltaic module, characterized in that, This includes solar cells as described in any one of claims 1 to 5 or solar cells prepared by the preparation method described in any one of claims 6 to 8.

10. An electrical device, characterized in that, Its power supply device includes a solar cell as described in any one of claims 1 to 5, a solar cell prepared according to the preparation method described in any one of claims 6 to 8, or a photovoltaic module as described in claim 9.

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