Solar cell, solar cell module and electric equipment

Abstract

The utility model relates to the technical field of solar cells, in particular to a solar cell, a solar cell module and a power utilization device.The solar cell comprises a first transmission layer, a perovskite layer, a second transmission layer, a transparent electrode layer, a protective layer and a metal electrode which are sequentially stacked, one of the first transmission layer and the second transmission layer is a hole transmission layer, and the other one is an electron transmission layer; and the protective layer comprises CeO2, WO3 or ZnO. The solar cell has better stability and longer service life.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of solar cells, in particular to a solar cell, a solar cell module and an electrical equipment. BACKGROUND

[0002] Perovskite solar cells are a new type of solar cells that use perovskite structure materials as light absorption layers. Such cells have attracted widespread attention due to their high photoelectric conversion efficiency, low-cost manufacturing process and simple preparation process, and in a tandem solar cell in which a wide-bandgap solar cell and a narrow-bandgap crystalline silicon solar cell are connected in series, perovskite solar cells have the potential to become an ideal candidate material for the wide-bandgap solar cell in the tandem cell. However, the low stability of perovskite solar cells limits their further industrial development. Therefore, the stability related technology of perovskite solar cells needs to be improved. UTILITY MODEL CONTENT

[0003] The present application aims to at least partially solve one of the technical problems in the related art. To this end, the present application proposes a solar cell with excellent stability, a solar cell module and an electrical equipment.

[0004] In a first aspect, the present application provides a solar cell. According to an embodiment of the present application, the solar cell comprises a first transport layer, a perovskite layer, a second transport layer, a transparent electrode layer, a protective layer and a metal electrode which are sequentially stacked, wherein one of the first transport layer and the second transport layer is a hole transport layer, and the other is an electron transport layer; the protective layer comprises CeO2, WO3 or ZnO. The protective layer described above has stable chemical properties, can effectively block water and oxygen from entering the inside of the cell and corroding the perovskite light absorption layer; at the same time, it can effectively absorb ultraviolet light to prevent ultraviolet light from damaging the perovskite light absorption layer, and will not cause light absorption loss; in addition, the protective layer has strong oxidizing properties, which can inhibit the reduction of the transparent electrode, so that the transparent electrode is not prone to reduction reaction and affect its optical and electrical properties, thereby the solar cell has high photoelectric conversion efficiency, and has better stability and longer service life. Moreover, the protective layer has good conductivity, does not affect the conduction between the metal electrode and the transparent electrode, and does not need to be additionally provided with a conduction structure.

[0005] According to an embodiment of the present application, the protective layer can comprise CeO2. Thereby, the stability of the solar cell can be further improved.

[0006] According to an embodiment of this application, the band gap of the protective layer is 3.0 eV to 4.0 eV. Perovskite is prone to decomposition under ultraviolet light irradiation. The protective layer, with the aforementioned band gap, can effectively absorb ultraviolet light, preventing ultraviolet light in sunlight from damaging the perovskite light-absorbing layer, thereby effectively improving the stability of the perovskite layer. At the same time, the aforementioned band gap is relatively wide and will not absorb visible light, thus preventing light absorption loss.

[0007] According to embodiments of this application, the thickness of the protective layer can be from 5 nm to 300 nm. This thickness effectively blocks water and oxygen, absorbs ultraviolet light, and does not increase the size of the solar cell.

[0008] In some embodiments, the protective layer covers the surface of the transparent electrode away from the perovskite layer. This provides better protection against water and oxygen, absorption of ultraviolet light, and inhibition of reduction of the transparent electrode.

[0009] According to an embodiment of this application, the solar cell further includes a transparent conductive substrate located on the side of the first transport layer away from the perovskite layer.

[0010] According to an embodiment of this application, the solar cell further includes: an intermediate interconnect layer located on the side of the first transport layer away from the perovskite layer; and a bottom cell located on the side of the intermediate interconnect layer away from the perovskite layer. Therefore, the photoelectric conversion efficiency of the solar cell can be significantly improved.

[0011] According to embodiments of this application, the bottom cell includes at least one of crystalline silicon solar cells, perovskite solar cells, copper indium gallium selenide solar cells, and organic photovoltaic cells.

[0012] A second aspect of this application provides a solar cell module. According to an embodiment of this application, the solar cell module includes the solar cell described above. This solar cell module exhibits better stability, longer lifespan, and higher photoelectric conversion efficiency.

[0013] A third aspect of this application provides an electrical appliance. According to an embodiment of this application, the electrical appliance includes the aforementioned solar cell module. This electrical appliance possesses all the features and advantages of the aforementioned solar cell module, which will not be repeated here.

[0014] This application has at least the following beneficial effects:

[0015] 1. The perovskite layer is prone to decomposition in water and oxygen environments, damaging the battery device. The protective layer provided in this application has stable chemical properties and can effectively block water and oxygen, inhibiting their erosion of the perovskite layer. Therefore, it is beneficial to improve the stability of perovskite battery devices.

[0016] 2. Perovskite is prone to decomposition under ultraviolet light irradiation. The protective layer in this application has a wide band gap, which effectively absorbs ultraviolet light and prevents ultraviolet light from damaging the perovskite layer, thereby improving the stability of the perovskite solar cell. Furthermore, because the protective layer has a wide band gap, it does not absorb visible light, thus preventing light absorption loss.

[0017] 3. The transparent electrode of perovskite solar cells is prone to reduction reaction, which affects its optical and electrical properties. The protective layer has strong oxidizing properties, which can inhibit the reduction of the transparent electrode. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a solar cell according to an embodiment of this application.

[0019] Figure 2 This is a schematic diagram of the structure of a solar cell according to another embodiment of this application.

[0020] Figure 3 These are the photoelectric conversion efficiency curves of the solar cells in Examples 2-4 and Comparative Example 2 of this application as a function of time.

[0021] Figure label:

[0022] 10: First battery cell; 11: First transport layer; 12: Perovskite layer; 13: Second transport layer; 14: Transparent electrode layer; 15: Protective layer; 16: Metal electrode; 17: Transparent conductive substrate; 18: Intermediate interconnect layer; 20: Bottom battery cell. Detailed Implementation

[0023] The embodiments of this application are described in detail below, with examples of these embodiments illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0024] This application is based on the inventor's discoveries and understanding of the following facts and problems:

[0025] The low stability of perovskite solar cells is mainly affected by the following factors: 1. Wide-bandgap perovskite itself suffers from problems such as photo-phase separation and ion migration, which adversely affect the stability of the cell. 2. Perovskite is prone to decomposition in water and oxygen environments, and the large amounts of water and oxygen present in the air can penetrate through the transport layer to the perovskite absorption layer, thereby eroding the perovskite absorption layer. 3. Perovskite decomposes under ultraviolet light irradiation. Sunlight contains strong ultraviolet light, and prolonged exposure to sunlight can damage the perovskite light-absorbing layer, causing device damage.

[0026] Although some researchers have proposed using potassium sorbate as an additive to passivate defects at perovskite grain boundaries and suppress phase separation, or to create a dense hydrophobic layer between the perovskite light-absorbing layer and the electron transport layer to improve device stability, these methods either fail to prevent damage to the perovskite light-absorbing layer caused by water and oxygen in the air or ultraviolet light from sunlight, or they are unable to effectively absorb ultraviolet light, thus failing to prevent damage to the perovskite light-absorbing layer.

[0027] In view of this, the inventors of this application propose to set a chemically stable wide-bandgap metal oxide protective layer between the transparent electrode and the metal electrode of the solar cell. This layer can effectively prevent water and oxygen from entering the cell and eroding the perovskite light-absorbing layer. It can also effectively absorb ultraviolet light, preventing ultraviolet light from damaging the perovskite light-absorbing layer without causing light absorption loss. Furthermore, the protective layer has strong oxidizing properties, which can inhibit the reduction of the transparent electrode layer and thus prevent it from affecting its own optical and electrical properties.

[0028] A first aspect of this application provides a solar cell. According to an embodiment of this application, referring to... Figure 1 The solar cell comprises a first transport layer 11, a perovskite layer 12, a second transport layer 13, a transparent electrode layer 14, a protective layer 15, and a metal electrode 16, stacked sequentially. One of the first transport layer 11 and the second transport layer 13 is a hole transport layer, and the other is an electron transport layer. The protective layer 15 comprises CeO2, WO3, or ZnO. The protective layer is chemically stable, effectively preventing water and oxygen from entering the cell and eroding the perovskite light-absorbing layer. It also effectively absorbs ultraviolet light, preventing damage to the perovskite light-absorbing layer without causing light absorption loss. Furthermore, the protective layer has strong oxidizing properties, inhibiting the reduction of the transparent electrode layer. This prevents the transparent electrode layer from undergoing a reduction reaction that could affect its optical and electrical properties, resulting in a solar cell with high photoelectric conversion efficiency, good stability, and a long lifespan. Moreover, the protective layer has good conductivity, not affecting the conduction between the metal electrode and the transparent electrode layer, eliminating the need for additional conductive structures.

[0029] According to embodiments of this application, the protective layer may include CeO2. Specifically, CeO2 possesses strong ultraviolet light absorption capacity, strong chemical stability, and strong oxidizing properties. Using CeO2 as the protective layer effectively prevents water and oxygen from entering the battery interior, thus effectively preventing the perovskite light-absorbing layer from being eroded, preventing ultraviolet light from damaging the perovskite light-absorbing layer, and inhibiting the reduction of the transparent electrode layer. Therefore, the stability of the solar cell can be further improved.

[0030] According to embodiments of this application, the band gap of the protective layer is 3.0 eV to 4.0 eV, specifically 3.0 eV, 3.1 eV, 3.2 eV, 3.3 eV, 3.4 eV, 3.5 eV, 3.6 eV, 3.7 eV, 3.8 eV, 3.9 eV, 4.0 eV, etc. Perovskite is prone to decomposition under ultraviolet light irradiation. The protective layer, with the aforementioned band gap, can effectively absorb ultraviolet light, preventing ultraviolet light in sunlight from damaging the perovskite light-absorbing layer, thereby effectively improving the stability of the perovskite layer. Simultaneously, the aforementioned band gap is relatively wide and does not absorb visible light, thus preventing light absorption loss.

[0031] According to embodiments of this application, the thickness of the protective layer can be from 5nm to 300nm, specifically such as 5nm, 25nm, 50nm, 75nm, 100nm, 125nm, 150nm, 175nm, 200nm, 225nm, 250nm, 275nm, and 300nm. With the above-mentioned thickness, it can effectively block water and oxygen, absorb ultraviolet light, and at the same time, it does not increase the size of the solar cell.

[0032] It is understood that the protective layer can be disposed on only a portion of the surface of the transparent electrode layer, or it can be disposed on the entire surface of the transparent electrode layer. It is also understood that the larger the area of ​​the transparent electrode layer covered by the protective layer, the better the effect on improving the stability of the perovskite solar cell. Therefore, in some embodiments, the protective layer covers the surface of the transparent electrode layer away from the perovskite layer. This results in better effects in blocking water and oxygen, absorbing ultraviolet light, and inhibiting the reduction of the transparent electrode layer.

[0033] According to embodiments of this application, the protective layer can be prepared by methods such as magnetron sputtering, vacuum evaporation, electron beam evaporation, or atomic layer deposition (ALD). It is understood that the protective layer can be formed in one step or through multiple sputtering and deposition processes. Taking vacuum evaporation as an example, a thin film can be deposited in a single step, followed by multiple depositions to obtain a protective layer of the target thickness. Specifically, the specific operations can be performed using conventional techniques, and this application does not impose any particular limitations.

[0034] It is understood that in the solar cell of this application, the main function of the metal electrode is to draw out the current generated in the solar cell. Therefore, it does not need to cover the entire surface of the protective layer; only appropriate metal wires are needed to achieve electrical connection. In some specific embodiments, the metal electrode can be two metal wires.

[0035] According to embodiments of this application, the specific material of the metal electrode is not particularly limited, as long as it can effectively achieve the conductivity function. As an example, the material of the metal electrode may include one or more of gold, silver, copper, and aluminum.

[0036] According to embodiments of this application, the metal electrode can be prepared by methods such as vacuum evaporation. For example, in a vacuum degree ≤ 5 × 10⁻⁶, -4 Under Pa conditions, 50nm–150nm metallic silver was deposited by vapor deposition at the following rate: wait.

[0037] According to embodiments of this application, the material of the transparent electrode layer can also be selected according to actual needs. In some specific embodiments, the transparent electrode layer may include one or more of transparent conductive films such as ITO (indium tin oxide), IZO (indium zinc oxide), and AZO (aluminum-doped zinc oxide). The thickness of the transparent electrode layer can be 50 nm to 200 nm.

[0038] According to embodiments of this application, the transparent electrode layer can be prepared by magnetron sputtering. For example, IZO can be used as the target material, and the transparent electrode layer can be formed by magnetron sputtering. Specifically, in an area ≤5×10⁻⁶... -4 Under a vacuum of Pa, argon gas was used as the carrier gas, and IZO of 80nm~100nm was sputtered as a transparent electrode layer using an RF power supply.

[0039] According to embodiments of this application, the specific materials of the hole transport layer include, but are not limited to, polymer materials, inorganic oxide materials, and metal-organic framework materials. As an example, the material of the hole transport layer includes mixed self-assembled monolayer molecules (SAMs), specifically including NiOx, [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz), 4-carbazolephosphonic acid (4PACz), 2-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-2PACz), poly-4-carbazolephosphonic acid (Poly-4PACz), and 4-(3,6-diphenyl-9H-carbazole-9-yl) At least one of butyl phosphate (Ph-4PACz), [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (2PACz), [2-(7H-dibenzocarbazole-7-yl)ethyl]phosphonic acid (Ph-2PACz), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine (PTAA), 4PADBCZ ([4-(7H-dibenzocarbazole-7-yl)butyl phosphate), 2PADBCZ ([4-(7H-dibenzocarbazole-7-yl)ethyl]phosphonic acid).

[0040] According to embodiments of this application, the hole transport layer can be prepared by spin coating. Specifically, a solution of Me-4PACz and MeO-2PACz with a concentration of 0.3 mg / mL to 2 mg / mL is prepared, and then they are mixed together at a volume ratio of 2:1 to 4:1 to prepare the desired mixed SAM solution. The SAM solution is spread evenly on a substrate and spin-coated at a speed of 2500 rpm to 3500 rpm for 20 s to 40 s. After spin coating, it is annealed on a hot plate at 50℃ to 150℃ for 5 min to 15 min.

[0041] It is understandable that when the solar cell is a single-junction solar cell, the hole transport layer can be formed on a transparent conductive substrate. Specifically, before depositing the hole transport layer, the transparent conductive substrate can be cleaned. As an example, the cleaning steps can be as follows: scrub the transparent conductive substrate with a cleaning agent, then ultrasonically clean it sequentially in a cleaning agent, deionized water, and anhydrous ethanol for 10-20 minutes, and dry it with a nitrogen gun. Finally, treat the cleaned transparent conductive substrate in plasma for 5-15 minutes.

[0042] According to embodiments of this application, the perovskite layer is primarily composed of an organometal halide semiconductor with the chemical formula ABX3. Here, A represents a monovalent organic or inorganic cation, such as methylamine ion CH3NH3. + Cesium ions (Cs) + etc.; B represents a divalent metal cation, such as lead ion Pb. 2+ Tin ions (Sn) 2+ etc.; X represents a monovalent halide anion, such as bromide ion Br-, iodide ion I-, etc. Specifically, the perovskite layer has excellent light absorption properties and charge separation ability, enabling it to absorb sunlight and generate excitons (electron-hole pairs), thereby achieving photoelectric conversion. As an example, the perovskite layer includes at least one of formamidinium lead iodide perovskite (FAPbI3), methylamine lead iodide (CH3NH3PbI3), cesium lead iodide (CsPbI3), methylamine lead bromide (MAPbBr3), and cesium lead bromide (CsPbBr3).

[0043] According to embodiments of this application, the perovskite layer can be prepared by spin coating. As an example, spin coating can be performed in two steps: first, a lead halide (PbX2) layer is formed by spin coating; then, formamidinium iodide (FAI) is spin-coated onto the lead halide layer. The FAI solution penetrates downwards into the PbX2 film, and the FAI reacts with PbX2 to form FAPbX3 perovskite. Residual solvent is removed by annealing. The spin coating temperature can be 22°C–24°C; the thickness of the resulting lead halide layer can be 300–600 nm; the perovskite annealing process can be carried out in ambient air at a humidity of 30%–40%; and the thickness of the resulting perovskite layer can be 700 nm–1200 nm.

[0044] In other embodiments, lead halide layers can also be prepared by vapor deposition.

[0045] It is understandable that, depending on the needs, the perovskite layer can also be passivated. Specifically, a passivating agent can be added to the perovskite layer; alternatively, a passivation layer can be formed on the perovskite layer after its formation. The passivating agent can be one or more of long-chain organic ammonium salts, aromatic organic ammonium salts, pyridine derivatives, and organic compounds with functional groups such as amino, carboxyl, and thiol groups. The concentration is 0.1 mg / mL to 2 mg / mL. As an example, a PEAI solution with a concentration of 0.1 mg / mL to 2 mg / mL can be prepared and spin-coated at a speed of 4500 to 5500 rpm for 20 to 40 seconds to form a passivation layer on the surface of the perovskite layer, thereby improving the efficiency and stability of the perovskite layer.

[0046] According to embodiments of this application, the main function of the electron transport layer is to effectively transport photogenerated electrons from the perovskite active layer to the external circuit, thereby improving the photoelectric conversion efficiency of the battery. Materials for the electron transport layer include, but are not limited to, metal oxides, organic compounds, and composite materials. Specifically, metal oxide electron transport materials include TiO2, ZnO, SnO2, etc.; organic compound electron transport materials include fullerene derivatives (PCBM), C... 60 Composite materials are materials made by combining two or more materials with different properties through physical or chemical methods, such as composites of metal oxides and organic compounds. The thickness of the electron transport layer can range from 10 nm to 50 nm.

[0047] According to embodiments of this application, the electron transport layer can be prepared by methods such as vacuum evaporation or ALD. It is understood that the electron transport layer can be a single-layer structure or a multi-layer structure. As an example, it can be prepared at a vacuum level ≤5×10⁻⁶. -4 Under Pa conditions, with The evaporation rate for depositing C at 20nm~40nm is [not specified]. 60 ① As the first electron transport layer; ② Using ALD technology, in C 60 A layer of 10nm-20nm tin oxide (SnO) is then deposited on top. x This forms the second electron transport layer.

[0048] In some embodiments, the solar cell of this application can be a single-junction solar cell or a tandem solar cell. In some embodiments, the single-junction solar cell can be a semi-transparent cell; the tandem solar cell can be a solar cell formed by stacking perovskite solar cells and any other type of solar cell.

[0049] According to an embodiment of this application, the solar cell is a single-junction solar cell, referring to...Figure 1 The solar cell also includes a transparent conductive substrate 17 located on the side of the first transport layer 11 away from the perovskite layer 12.

[0050] It is understood that a transparent conductive substrate can be conductive glass. Specifically, conductive glass can serve as the electrode of a battery, improving the battery's light absorption and conversion efficiency. As examples, conductive glass includes, but is not limited to, transparent conductive oxide glass and glass-ceramic materials; among them, transparent conductive oxide glass mainly includes FTO (fluorine-doped tin oxide) glass, ITO (indium tin oxide) glass, and ZnO (zinc oxide) glass; glass-ceramic materials include high-temperature ceramic materials composed of alumina, silicates, borates, etc.

[0051] According to an embodiment of this application, the solar cell is a tandem cell, referring to... Figure 2 The solar cell further includes: an intermediate interconnect layer 18 located on the side of the first transport layer 11 away from the perovskite layer 12; and a bottom cell 20 located on the side of the intermediate interconnect layer 18 away from the perovskite layer 12. Therefore, the photoelectric conversion efficiency of this solar cell can be significantly improved.

[0052] According to embodiments of this application, the bottom cell includes at least one of crystalline silicon solar cells, perovskite solar cells, copper indium gallium selenide solar cells, and organic photovoltaic cells.

[0053] It is understood that the base cell can have the necessary structure and components of a conventional solar cell. Taking a crystalline silicon solar cell as an example, it may include ① a crystalline silicon substrate; ② a first amorphous silicon layer disposed on one side of the crystalline silicon substrate; ③ a second amorphous silicon layer disposed on the other side of the crystalline silicon substrate, the second amorphous silicon layer being connected to an intermediate interconnect layer, and the second amorphous silicon layer having an opposite conductivity type to the first amorphous silicon layer.

[0054] According to embodiments of this application, the intermediate interconnect layer can be made of one or more transparent conductive films such as ITO and IZO, with a thickness of 20nm to 50nm. Specifically, ITO can be used as a target material and deposited onto the battery using magnetron sputtering. Using an ITO target, the vacuum is evacuated to ≤5×10⁻⁶. -4 After Pa, argon gas is introduced, and the radio frequency power supply is turned on to deposit an ITO layer. The sputtering power is 50W to 150W, and the deposition thickness is 20nm to 50nm.

[0055] The following section uses the perovskite / crystalline silicon tandem solar cell structure as an example to explain its specific structure and fabrication process in detail.

[0056] The perovskite / crystalline silicon tandem solar cell comprises a crystalline silicon substrate, an intermediate interconnect layer, a hole transport layer, a perovskite layer, an electron transport layer, a transparent top electrode, a protective layer, and a metal electrode, stacked sequentially. The transparent conductive substrate is ITO (indium tin oxide) conductive glass, the intermediate interconnect layer is ITO, the hole transport layer (HTL) uses a hybrid self-assembled monolayer (SAM), and the electron transport layer (ETL) uses C… 60 SnO and ALD x The transparent electrode layer uses indium zinc oxide (IZO), the protective layer uses CeO2, and the metal electrode uses silver (Ag).

[0057] The specific preparation method is as follows:

[0058] Crystalline silicon solar cell: includes ① a crystalline silicon substrate; ② a first amorphous silicon layer disposed on one side of the crystalline silicon substrate; ③ a second amorphous silicon layer disposed on the other side of the crystalline silicon substrate, the second amorphous silicon layer being connected to an intermediate interconnect layer, and the second amorphous silicon layer having the opposite conductivity type to the first amorphous silicon layer.

[0059] Intermediate interconnect layer: ITO is deposited onto the crystalline silicon solar cell substrate using magnetron sputtering as the target material. Specifically, an ITO target is used, and the vacuum is evacuated to ≤5×10⁻⁶. -4 After Pa, argon gas is introduced, and the radio frequency power supply is turned on to deposit the ITO layer. The sputtering power is 50W to 150W, and the deposition thickness is 20nm to 50nm. Before depositing the intermediate interconnect layer, the ITO target is pre-sputtered for 5min to 15min.

[0060] Cleaning the substrate: Treat the above substrate with a plasma cleaner for 8 to 10 minutes.

[0061] Preparation of the hole transport layer: Me-4PACz and MeO-2PACz solutions, each with a concentration of 0.3–0.8 mg / mL, were prepared and then mixed together at a volume ratio of 2:1 to 4:1 to obtain the desired mixed SAM solution. The SAM solution was spread evenly on the substrate and spin-coated at 2500–3500 rpm for 20–40 seconds. After spin-coating, the substrate was annealed on a hot plate at 50–150°C for 5–15 minutes.

[0062] Preparation of lead halide layer: 548.8 mg lead iodide (PbI2), 187.2 mg lead bromide (PbBr2), and 28.7 mg cesium chloride (CsCl) were dissolved in 1 mL of a mixed solution of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), with a DMF to DMSO volume ratio of 9:1, to prepare a lead halide precursor solution. This solution was heated and stirred on a hot stage at 40℃–50℃ for 2–6 h. 50–150 μL of the lead halide precursor solution was spread evenly on the surface of the hole transport layer substrate and spin-coated at 1000–2000 rpm for 20–40 s. After spin-coating, the solution was annealed on a hot stage at 50–100℃ for 0.5–1.5 min to form a yellow transparent PbX2 layer.

[0063] Preparation of the perovskite layer: Dissolve 102 mg formamidin iodine (FAI), 10.2 mg methylamine chloride (MACl), and 10.2 mg methylamine bromide (MABr) in 1 mL of isopropanol (IPA) to prepare an amine salt solution, and let it stand for 2–6 h. Take 100–200 μL of the prepared amine salt solution and spin-coat it at 1500–2000 rpm for 20–40 s. Then, drop it onto the surface of the lead halide substrate 3–5 s after the spin-coating begins. After spin-coating, anneal on a hot stage at 100–200 °C for 10–20 min (annealing atmosphere is dry air) to form the perovskite layer.

[0064] Surface passivation: Prepare a PEAI solution with a concentration of 0.5-1.5 mg / mL, spin-coat it at a speed of 4500-5500 rpm for 20-40 s to form a passivation layer on the surface of the perovskite substrate.

[0065] Preparation of electron transport layer: ① Under a vacuum degree ≤5×10 -4 Under Pa conditions, with The evaporation rate, evaporating 20-40 nm of C 60 ① As the first electron transport layer; ② Using ALD technology, in C 60 A layer of 10nm-20nm tin oxide (SnO) is then deposited on top. x A second electron transport layer is formed. The pressure is maintained at 10–20 Pa, the temperature at 50–100 °C, and nitrogen is used as the purging gas at a flow rate of 40–80 sccm. Tetramethylaminotin (TDMASn) is used as the deposition precursor, and H₂O is used as the oxygen source, both at a flow rate of 20–40 sccm. The growth rate of the SnOx film is approximately 0.05–0.15 nm / cycle.

[0066] Fabrication of the transparent top electrode: IZO was used as the target material and deposited onto the electron transport layer by magnetron sputtering. (≤5×10⁻⁶) -4Under a vacuum of Pa, argon gas was used as the carrier gas, and IZO of 80nm~100nm was sputtered as a transparent electrode layer using an RF power supply.

[0067] Preparation of protective layer: CeO2 is used as target material and is deposited onto the transparent electrode layer by magnetron sputtering with a sputtering thickness of 5nm to 300nm.

[0068] Preparation of metal electrode layer: under vacuum degree ≤5×10 -4 Under Pa conditions, 50–150 nm metallic silver was deposited by vapor deposition at the following rate:

[0069] A second aspect of this application provides a solar cell module. According to an embodiment of this application, the solar cell module includes the solar cell described above. This solar cell module exhibits better stability, longer lifespan, and higher photoelectric conversion efficiency.

[0070] A third aspect of this application provides an electrical appliance. According to an embodiment of this application, the electrical appliance includes the aforementioned solar cell module. This electrical appliance possesses all the features and advantages of the aforementioned solar cell module, which will not be repeated here.

[0071] The embodiments of this application are described in detail below.

[0072] Example 1

[0073] The fabrication process of perovskite semi-transparent solar cells is as follows:

[0074] 1) Substrate cleaning: The FTO conductive glass was wiped with a cleaning agent, then ultrasonicated with cleaning agent, deionized water, and anhydrous ethanol for 15 minutes in sequence, dried with nitrogen, and then treated in a plasma cleaner for 8 minutes.

[0075] 2) Preparation of hole transport layer: Mix 0.5 mg / mL Me-4PACz ethanol solution and 0.5 mg / mL MeO-2PACz ethanol solution at a volume ratio of 3:1 to obtain a mixed SAM solution; spread the mixed SAM solution on the substrate and spin-coat at 3000 rpm for 30 s; after spin-coating, anneal on a hot stage at 100℃ for 10 min to obtain the hole transport layer;

[0076] 3) Preparation of lead halide layer: Dissolve 548.8 mg lead iodide (PbI2), 187.2 mg lead bromide (PbBr2), and 28.7 mg cesium chloride (CsCl) in 1 mL of a mixed solution of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), with a DMF to DMSO volume ratio of 9:1, to prepare a lead halide precursor solution. Heat and stir the solution on a 45°C hot plate for 4 h. Take 100 μL of the lead halide precursor solution and spread it evenly on the surface of the hole transport layer. Spin-coat the solution at 1500 rpm and 750 rpm / s for 30 s. After spin-coating, anneal the solution on a 70°C hot plate for 1 min to form a yellow transparent PbX2 layer.

[0077] 4) Preparation of the perovskite layer: Dissolve 102 mg formamidinium iodine (FAI), 10.2 mg methylamine chloride (MACl), and 10.2 mg methylamine bromide (MABr) in 1 mL of isopropanol (IPA) to prepare an amine salt solution, and let it stand for 4 h. Take 150 μL of the prepared amine salt solution and spin-coat it at 1700 rpm for 30 s. Then, drop it onto the surface of the lead halide layer in the 3rd to 5th seconds after the spin-coating begins. After spin-coating, anneal it on a hot plate at 150 °C for 15 min (annealing atmosphere is dry air) to form the perovskite layer.

[0078] 5) Phenylethyl ammonium iodide (PEAI, molecular formula C8H) 11 Ni) is dissolved in IPA to form a PEAI solution with a concentration of 1 mg / mL; the PEAI solution is spin-coated at 5000 rpm for 30 s to form a PEAI layer;

[0079] 6) Fabrication of the electron transport layer: ① Under a vacuum of 10 -4 Under Pa conditions, with The evaporation rate will C 60 Powder is vapor-deposited onto the surface of the PEAI layer to form an electron transport layer with a thickness of 20 nm; ② ALD technology is used to deposit powder onto the surface of the PEAI layer. 60 A 10nm layer of tin oxide (SnO) is then deposited on top. x This forms the second electron transport layer. The pressure was maintained at 15 Pa and the temperature at 100 °C. Nitrogen gas was used as the purging gas at a flow rate of 60 sccm. Tetramethylaminotin (TDMASn) was used as the deposition precursor, and H2O was used as the oxygen source, both at a flow rate of 30 sccm. x The growth rate of the thin film is approximately 0.1 nm / cycle.

[0080] 7) Fabrication of a transparent top electrode: IZO was used as the target material and deposited onto the electron transport layer by magnetron sputtering. (5×10⁻⁶) -4Under a vacuum of Pa, argon was used as the carrier gas, and 90 nm IZO was sputtered as a transparent electrode layer using an RF power supply.

[0081] 8) Preparation of protective layer: CeO2 is used as target material and is deposited onto the transparent electrode layer by magnetron sputtering with a sputtering thickness of 100 nm.

[0082] 9) Fabrication of the metal electrode layer: under a vacuum of 5×10⁻⁶ -4 Under Pa conditions, 100 nm metallic silver was deposited by vapor deposition at the following rate:

[0083] Example 2

[0084] The fabrication process for crystalline silicon / perovskite tandem solar cells is as follows:

[0085] 1. Fabrication of crystalline silicon bottom solar cells

[0086] 1) A silicon substrate is provided, and a substrate passivation layer, a P-type substrate doped layer and a first transparent electrode layer are sequentially formed on one side surface of the silicon substrate; 2) A first metal electrode layer is formed on the surface of the first transparent electrode layer; 3) A substrate surface passivation layer and an N-type substrate doped layer are sequentially formed on the other side surface of the silicon substrate.

[0087] The process for the substrate passivation layer and the substrate surface passivation layer is wet chemical alkaline texturing. By controlling the concentration of the alkaline solution, the textured surface size of the silicon substrate is controlled to be 5 μm.

[0088] 2. Fabrication of the intermediate interconnect layer

[0089] ITO was used as the target material and deposited onto a crystalline silicon substrate using magnetron sputtering. (5×10) -4 Under a vacuum of Pa, argon gas was used as the carrier gas, and 40 nm ITO was sputtered using an RF power supply as the intermediate interconnect layer.

[0090] 3. Fabrication of perovskite solar cells:

[0091] 1) Substrate cleaning: The intermediate interconnect layer was ultrasonically cleaned with anhydrous ethanol for 30 minutes, dried with nitrogen, and then treated in a plasma cleaner for 8 minutes.

[0092] 2) Preparation of hole transport layer: Mix 0.5 mg / mL Me-4PACz ethanol solution and 0.5 mg / mL MeO-2PACz ethanol solution at a volume ratio of 3:1 to obtain a mixed SAM solution; spread the mixed SAM solution on the intermediate interconnect layer, spin-coat at 3000 rpm for 30 s, and anneal on a hot plate at 100℃ for 10 min after spin-coating to obtain the hole transport layer;

[0093] 3) Preparation of the perovskite light-absorbing layer

[0094] a. Preparation of the inorganic salt layer: Approximately 1g of lead iodide (PbI₂) and approximately 100mg of lead bromide (PbBr₂) were placed separately in evaporation crucibles; at 5×10⁻⁶... -4 Under a vacuum of Pa, respectively with and At a rate of [missing information], lead iodide powder and lead bromide powder were deposited on the surface of the hole transport layer to obtain an inorganic salt layer with a thickness of approximately 300 nm.

[0095] b. Weigh 36.6 mg formamidine bromide (FABr), 28.8 mg formamidine iodide (FAI) and 7.8 mg methylamine chloride (MACl), dissolve them in 1 mL of isopropanol (IPA) to prepare an amine salt solution, let stand for 4 h, spin coat at 2700 rpm for 30 s, add 100 μL of amine salt solution to the lead halide layer in the 3rd to 5th s of spin coating, after spin coating, anneal at 150 °C for 15 min in an air atmosphere with a relative humidity of 35% to form a perovskite film;

[0096] c. Place approximately 5 mg of lithium fluoride (LiF) into a vapor deposition crucible; heat at 5 × 10⁻⁶ ppm. -4 At a vacuum of Pa, The rate at which lithium fluoride is deposited onto the surface of the perovskite layer serves as an interface passivation layer.

[0097] 4) Fabrication of the electron transport layer: ① Under a vacuum of 10 -4 Under Pa conditions, with The evaporation rate will C 60 Powder is deposited onto the surface of the LiF layer to form a C layer with a thickness of 30 nm. 60 ① As the first electron transport layer; ② Using ALD technology, in C 60 A 10nm layer of tin oxide (SnO) is then deposited on top. x This forms the second electron transport layer. The pressure was maintained at 15 Pa and the temperature at 100 °C. Nitrogen gas was used as the purging gas at a flow rate of 60 sccm. Tetramethylaminotin (TDMASn) was used as the deposition precursor, and H2O was used as the oxygen source, both at a flow rate of 30 sccm. x The growth rate of the thin film is approximately 0.1 nm / cycle.

[0098] 5) Fabrication of the transparent electrode layer: IZO was used as the target material and deposited onto the electron transport layer by magnetron sputtering. (5×10⁻⁶) -4 Under a vacuum of Pa, argon was used as the carrier gas, and 100 nm of IZO was sputtered as a transparent electrode layer using an RF power supply.

[0099] 6) Preparation of protective layer: CeO2 is used as target material and is deposited onto the transparent electrode layer by magnetron sputtering with a sputtering thickness of 100 nm.

[0100] 7) Fabrication of the metal electrode: under a vacuum of 10... -4 Under Pa conditions, with A silver metal electrode with a thickness of 140 nm was formed by evaporation at a certain evaporation rate, resulting in a perovskite solar cell.

[0101] Example 3

[0102] Same as Example 2, except that the protective layer material is WO3.

[0103] Example 4

[0104] Same as Example 2, except that the protective layer material is ZnO.

[0105] Comparative Example 1

[0106] Same as Example 1, except that there is no protective layer.

[0107] Comparative Example 2

[0108] Same as Example 2, except that there is no protective layer.

[0109] Performance testing:

[0110] 1. The JV (current density-voltage) of the solar cells prepared in the above embodiments and comparative examples was tested:

[0111] Test method: JV testing was conducted using a Keithley 2400 source under simulated amplitude modulation, and a solar simulator based on a steady-state xenon lamp was used to simulate 1.5G illumination (100mW / cm²). 2 The effective areas of the single-junction solar cell and the tandem solar cell are 0.16 cm², respectively. 2 and 1cm 2 The JV curve was obtained, and the short-circuit current density Jsc, open-circuit voltage Voc, fill factor FF, and photoelectric conversion efficiency (PCE) of the battery were calculated from the JV curve. The test results are shown in Table 1. The test was conducted under normal atmospheric conditions, and the photoelectric conversion efficiency of the solar cell in air over time is shown in the curve. Figure 3 As shown.

[0112] Table 1

[0113]

[0114] From Table 1 and Figure 1The data shown indicates that by adding a protective layer, the open-circuit voltage and photoelectric conversion efficiency of both single-junction solar cells and tandem solar cells are significantly improved. This demonstrates that adding a protective layer can effectively improve the stability of perovskite solar cells, thereby enhancing their performance.

[0115] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0116] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A solar cell, characterized in that, It includes a first transport layer, a perovskite layer, a second transport layer, a transparent electrode layer, a protective layer, and a metal electrode, which are stacked sequentially, wherein: One of the first transport layer and the second transport layer is a hole transport layer, and the other is an electron transport layer; The protective layer includes CeO2, WO3 or ZnO.

2. The solar cell according to claim 1, characterized in that, The protective layer comprises CeO2.

3. The solar cell according to claim 1, characterized in that, The band gap of the protective layer is 3.0 eV to 4.0 eV.

4. The solar cell according to claim 1, characterized in that, The thickness of the protective layer is 5nm to 300nm.

5. The solar cell according to claim 1, characterized in that, The protective layer covers the surface of the transparent electrode layer away from the perovskite layer.

6. The solar cell according to claim 1, characterized in that, It also includes a transparent conductive substrate located on the side of the first transport layer away from the perovskite layer.

7. The solar cell according to claim 1, characterized in that, Also includes: An intermediate interconnect layer is located on the side of the first transport layer away from the perovskite layer; The bottom cell is located on the side of the intermediate interconnect layer away from the perovskite layer.

8. The solar cell according to claim 7, characterized in that, The base cell includes at least one of crystalline silicon solar cells, perovskite solar cells, copper indium gallium selenide solar cells, and organic photovoltaic cells.

9. A solar cell module, characterized in that, The solar cell includes any one of claims 1 to 8.

10. An electrical appliance, characterized in that, Includes the solar cell module as described in claim 9 or the solar cell as described in any one of claims 1 to 8.

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