Perovskite solar cell and preparation method thereof
By adding small-molecule expanding agents to the perovskite precursor solution, the crystallization and interface modification of the perovskite layer are regulated, thus solving the lattice and interface defect problems of perovskite solar cells and improving the performance and stability of the cells.
Patent Information
- Application Number
- CN202511130963.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-13
- Publication Date
- 2025-11-18
AI Technical Summary
Perovskite solar cells suffer from lattice and interface defects during film formation, leading to non-radiative energy loss, affecting cell performance and stability, and hindering their industrialization.
By adding a small molecule expanding agent to the perovskite precursor solution, the non-radiative energy loss can be reduced and a protective layer can be formed on the perovskite surface, thereby improving device stability, by regulating the crystallization behavior and interface modification of the perovskite layer.
The use of small-molecule expanders improves the performance and stability of perovskite solar cells, reduces non-radiative energy loss, and enhances the environmental stability of the devices.
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Figure CN120981074A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of perovskite solar cells, and particularly relates to a perovskite solar cell and a preparation method thereof. BACKGROUND
[0002] The third generation solar cells include organic solar cells, dye-sensitized solar cells and perovskite solar cells. Compared with organic and dye-sensitized solar cells, the perovskite solar cells have simple preparation process, low cost and higher photoelectric conversion efficiency, and almost all the advantages of other solar cells. Therefore, the perovskite solar cells have attracted extensive attention and are considered as the third generation photovoltaic technology which is expected to replace the traditional crystalline silicon photovoltaic cells.
[0003] However, the perovskite will generate obvious lattice defects in the film forming process, and the defects at the interface will cause non-radiative energy loss, thereby directly affecting the performance and stability of the battery, and thus affecting the industrialization development of the perovskite solar cell.
[0004] The small molecule expanding agent refers to a kind of compound with small molecular weight, which realizes the expanding effect by introducing voids, changing the microstructure of the material or affecting the interaction of the material. The main characteristics and functions of the small molecule expanding agent include: 1) small molecular weight makes it easier to diffuse and disperse in the material; 2) can be combined with the matrix material through physical or chemical interaction to change its performance; 3) adjust the crystallization process of the material, adjust the morphology and size of the crystal, and then optimize the microstructure of the material; 4) improve the mechanical properties and thermal stability of the material.
[0005] The above advantages can be used in the perovskite solar cell to improve the performance and stability of the perovskite solar cell. SUMMARY
[0006] The present application aims at the deficiencies of the prior art, and provides a perovskite solar cell and a preparation method thereof.
[0007] The purpose of the present application is achieved by the following technical solutions: In a first aspect, the present application provides a perovskite solar cell, which is from bottom to top a substrate, a hole transport layer, a perovskite layer, an electron transport layer and an electrode layer; or the perovskite solar cell is from bottom to top a substrate, an electron transport layer, a perovskite layer, a hole transport layer and an electrode layer.
[0008] In a second aspect, the present application further provides a preparation method of a perovskite solar cell, comprising the following steps: (1) using ITO glass as a substrate; (2) spin-coating a hole transport layer with a thickness of 0.5-10 nm on top of the substrate; (3) dissolving a perovskite precursor in an organic solvent to obtain a perovskite precursor solution with a concentration of 1.5 mol / L; then adding 5-15 mg of a small-molecule swelling agent to 1 mL of the perovskite precursor solution, stirring until the perovskite precursor is completely dissolved to obtain a small-molecule perovskite precursor solution; then spin-coating the small-molecule perovskite precursor solution on the hole transport layer to obtain a perovskite layer with a thickness of 100-1000 nm after heat treatment; (4) sequentially evaporating an electron transport layer and an electrode layer with a thickness of 5-50 nm on top of the perovskite layer; or (1) using ITO glass as a substrate; (2) evaporating an electron transport layer with a thickness of 5-50 nm on top of the substrate; (3) dissolving a perovskite precursor in an organic solvent to obtain a perovskite precursor solution with a concentration of 1.5 mol / L; then adding 5-15 mg of a small-molecule swelling agent to 1 mL of the perovskite precursor solution, stirring until the perovskite precursor is completely dissolved to obtain a small-molecule perovskite precursor solution; then spin-coating the small-molecule perovskite precursor solution on the electron transport layer to obtain a perovskite layer with a thickness of 100-1000 nm after heat treatment; (4) spin-coating a hole transport layer with a thickness of 0.5-10 nm on top of the perovskite layer; (5) then evaporating an electrode layer on top of the hole transport layer.
[0009] Further, the material of the hole transport layer is a self-assembled molecular layer material containing a phosphoric acid group.
[0010] Further, the self-assembled molecular layer material containing a phosphoric acid group is one or several of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid, and [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid.
[0011] Further, the perovskite precursor is ABX3, wherein A is a cation comprising one or more of CH3NH3 + , HC(NH2)2 + , and Cs + ; B is a metal ion comprising one or more of Pb 2+ , Sn 2+ , and Sr 2+ ; and X is a halogen ion comprising Br.- , I - and Cl - one or more of the group consisting of F, Cl, Br, I, CN, and NCO.
[0012] Further, the small molecule expanding agent is a small molecule organic compound, an inorganic small molecule, or a functional small molecule.
[0013] Further, the small molecule organic compound includes but is not limited to benzimidazole small molecules, furan small molecules, and polymer small molecules; the inorganic small molecule includes but is not limited to cesium salt or lithium salt; and the functional small molecule includes but is not limited to nitrogen heterocyclic compounds or carbon heterocyclic compounds.
[0014] Further, the material of the electron transport layer is one or more of fullerene or fullerene derivatives.
[0015] Further, the material of the electrode layer is one or more of gold, silver, copper, and aluminum.
[0016] The beneficial effects of the present application are: by adding a small molecule expanding agent to the perovskite precursor solution, the perovskite layer is modified in structure, the crystal defects and film stress of the perovskite are regulated, and the small molecule expanding agent also has a modification effect on the interface, which reduces the non-radiative energy loss of the perovskite solar cell, and at the same time, the hydrophobicity of the small molecule expanding agent can form a protective layer on the perovskite surface, reduce the invasion of water, and further improve the environmental stability of the device. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 is a schematic diagram of a cross-sectional structure of a perovskite solar cell; Figure 2 is another schematic diagram of a cross-sectional structure of a perovskite solar cell; Figure 3 is a stability comparison diagram of perovskite solar cells prepared by Example A2, Example B2, Example C2, and Comparative Example D1; In the figure, 1 is a substrate; 2 is a hole transport layer; 3 is a perovskite layer; 4 is an electron transport layer; and 5 is an electrode layer. DETAILED DESCRIPTION
[0018] In order to make the purpose, technical solutions and advantages of the present application more clear and clear, the present application is further described in detail in combination with the drawings and examples, and it should be understood that the specific examples described here are only used to explain the present application, rather than all examples. Based on the examples in the present application, all other examples obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0019] The experimental methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials described are all commercially available unless otherwise specified.
[0020] Solar cell is a kind of light-emitting semiconductor wafer using sunlight to generate electricity, also known as "solar chip" or "photocell", it can output voltage and generate current in the case of loop as long as it is illuminated under certain illumination conditions. In physics, it is called solar photovoltaic, simply called photovoltaic. In order to facilitate and clearly describe the preparation method of the solar cell of the present application and the solar cell thereof, the exemplary embodiments of the present application are described below in conjunction with the drawings, which include various details of the embodiments of the present application to help understanding, which should be regarded as only exemplary. Therefore, those skilled in the art should realize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Similarly, in order to be clear and concise, the description in the following description omits the description of the known functions and structures.
[0021] Figure 1 A cross-sectional structure schematic diagram of a perovskite solar cell provided by the present application is shown in Figure 1. Figure 1 As shown in Figure 1, the perovskite solar cell provided by the present application comprises, from bottom to top, a substrate 1, a hole transport layer 2, a perovskite layer 3, an electron transport layer 4 and an electrode layer 5.
[0022] Figure 2 Another cross-sectional structure schematic diagram of a perovskite solar cell provided by the present application is shown in Figure 2. Figure 2 As shown in Figure 2, the perovskite solar cell provided by the present application comprises, from bottom to top, a substrate 1, an electron transport layer 4, a perovskite layer 3, a hole transport layer 2 and an electrode layer 5.
[0023] The present application provides a preparation method of a perovskite solar cell, comprising the following steps: (1) ITO glass is used as a substrate.
[0024] (2) A hole transport layer with a thickness of 0.5-10 nm is spin-coated on the substrate.
[0025] The material of the hole transport layer is a self-assembled molecular layer material containing a phosphate group. The self-assembled molecular layer material containing a phosphate group is one or several of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid and [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid. In the perovskite cell, the hole transport layer mainly plays a role of collecting and transporting holes and realizing effective separation of electrons and holes.
[0026] (3) dissolving the perovskite precursor in an organic solvent to obtain a perovskite precursor solution with a concentration of 1.5 mol / L; then adding 5-15 mg of a small-molecule swelling agent to 1 mL of the perovskite precursor solution, stirring until the perovskite precursor is completely dissolved to obtain a small-molecule perovskite precursor solution; and then spin-coating the small-molecule perovskite precursor solution on the hole transport layer to obtain a perovskite layer with a thickness of 100-1000 nm after heat treatment.
[0027] The perovskite precursor is ABX3, wherein A is a cation comprising one or more of CH3NH3 + , (HC(NH)2)2 + , and Cs + ; B is a metal ion comprising one or more of CH3NH3 + , HC(NH2)2 + , and Cs + ; and X is a halogen ion comprising one or more of Br - , I - , and Cl - .
[0028] The small-molecule swelling agent is a small-molecule organic compound, an inorganic small molecule, or a functional small molecule. The small-molecule organic compound includes but is not limited to benzimidazole small molecules, furan small molecules, and polymer small molecules; the inorganic small molecule includes but is not limited to cesium salts or lithium salts; and the functional small molecule includes but is not limited to nitrogen heterocyclic compounds or carbon heterocyclic compounds.
[0029] In the prior art, since no small-molecule swelling agent is added to the perovskite precursor solution, the crystallization of the perovskite layer is not easy to control and there is non-radiative energy loss at the interface, which causes the performance of the perovskite solar cell to decrease and the stability to be poor. Therefore, the embodiments of the present application add a small-molecule swelling agent to the perovskite precursor solution to regulate the crystallization behavior of the perovskite and reduce the non-radiative energy loss at the interface, thereby improving the performance and stability of the perovskite solar cell.
[0030] For the small-molecule swelling agent, its role is to interact with the perovskite precursor solution, making the crystallization in the perovskite film formation process more easily controllable and the non-radiative energy loss between interfaces reduced.
[0031] For the perovskite layer, the thickness directly affects the photoelectric conversion efficiency of the perovskite solar cell. A thicker perovskite layer can absorb more photons, thereby increasing the short-circuit current density. However, a perovskite layer that is too thick will result in an increase in the carrier transport path, increasing the recombination loss and reducing the open-circuit voltage and fill factor. Therefore, the thickness of the perovskite layer in the present embodiment is set to 100-1000 nm, which on the one hand ensures the photoelectric conversion efficiency of the perovskite solar cell and on the other hand minimizes the recombination loss.
[0032] (4) An electron transport layer with a thickness of 5-50 nm and an electrode layer are sequentially deposited above the perovskite layer.
[0033] The material of the electron transport layer is one or more of fullerenes or fullerene derivatives (such as fullerenes C60, fullerene derivatives PCBM and ICBA, etc.). Specifically, the electron transport layer can enhance the separation effect of electrons and holes, thereby effectively improving the conversion efficiency of the solar cell, while being able to improve the transmission rate of electrons, reduce the impedance of the current and increase the overall current of the perovskite solar cell.
[0034] The material of the electrode layer is usually a metal material and can include one or more of gold, silver, copper and aluminum.
[0035] The present application also provides a preparation method of a perovskite solar cell, comprising the following steps: (1) ITO glass is used as a substrate.
[0036] (2) An electron transport layer with a thickness of 5-50 nm is deposited above the substrate.
[0037] (3) A perovskite precursor is dissolved in an organic solvent to obtain a perovskite precursor solution with a concentration of 1.5 mol / L; then 5-15 mg of a small molecule swelling agent is added to 1 mL of the perovskite precursor solution, and the mixture is stirred until the perovskite precursor is completely dissolved to obtain a small molecule perovskite precursor solution; the small molecule perovskite precursor solution is then spin-coated on the electron transport layer, and after heat treatment, a perovskite layer with a thickness of 100-1000 nm is obtained.
[0038] (4) A hole transport layer with a thickness of 0.5-10 nm is spin-coated above the perovskite layer.
[0039] (5) Then, an electrode layer is deposited above the hole transport layer.
[0040] Embodiment A1: A preparation method of a perovskite solar cell, comprising the following steps: (1) ITO glass is used as a substrate.
[0041] (2) spin-coating a hole transport layer with a thickness of 0.5 nm on top of the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazole-9-yl) ethyl] phosphonic acid.
[0042] (3) dissolving 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255 )3) with a concentration of 1.5 mol / L; then adding 5 mg of benzothiazole (a small-molecule swelling agent) into 1 mL of the perovskite precursor solution, stirring for more than 4 h at room temperature until the perovskite precursor is completely dissolved to obtain a small-molecule perovskite precursor solution; and spin-coating the small-molecule perovskite precursor solution on the electron transport layer to obtain a perovskite layer with a thickness of 600 nm after heat treatment.
[0043] (4) sequentially evaporating an electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm on top of the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0044] Embodiment A2: A method for preparing a perovskite solar cell, comprising the following steps: (1) using ITO glass as a substrate.
[0045] (2) spin-coating a hole transport layer with a thickness of 0.5 nm on top of the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazole-9-yl) ethyl] phosphonic acid.
[0046] (3) dissolving 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255)3); 15 mg benzothiazole (small molecule swelling agent) is then added to 1 mL of the perovskite precursor solution, which is stirred at room temperature for more than 4 h until the perovskite precursor is completely dissolved to obtain a small molecule perovskite precursor solution; the small molecule perovskite precursor solution is then spin-coated on the electron transport layer, and a perovskite layer with a thickness of 600 nm is obtained after heat treatment.
[0047] (4) An electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm are sequentially evaporated above the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0048] Embodiment A3: A method for preparing a perovskite solar cell, comprising the following steps: (1) ITO glass is used as a substrate.
[0049] (2) A hole transport layer with a thickness of 0.5 nm is spin-coated above the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazol-9-yl)ethyl]phosphonic acid.
[0050] (3) 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 are dissolved in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255 )3); 15 mg benzothiazole (small molecule swelling agent) is then added to 1 mL of the perovskite precursor solution, which is stirred at room temperature for more than 4 h until the perovskite precursor is completely dissolved to obtain a small molecule perovskite precursor solution; the small molecule perovskite precursor solution is then spin-coated on the electron transport layer, and a perovskite layer with a thickness of 600 nm is obtained after heat treatment.
[0051] (4) An electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm are sequentially evaporated above the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0052] Embodiment B1: A method for preparing a perovskite solar cell, comprising the following steps: (1) ITO glass is used as a substrate.
[0053] (2) spin-coating a hole transport layer with a thickness of 0.5 nm on top of the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazole-9-yl) ethyl] phosphonic acid.
[0054] (3) dissolving 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255 )3) with a concentration of 1.5 mol / L; then adding 5 mg of anhydrous cesium carbonate (a small molecule swelling agent) into 1 mL of the perovskite precursor solution, stirring for more than 4 h at room temperature until the perovskite precursor is completely dissolved to obtain a small molecule perovskite precursor solution; and then spin-coating the small molecule perovskite precursor solution on the electron transport layer to obtain a perovskite layer with a thickness of 600 nm after heat treatment.
[0055] (4) sequentially evaporating an electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm on top of the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0056] Embodiment B2: A method for preparing a perovskite solar cell, comprising the following steps: (1) using ITO glass as a substrate.
[0057] (2) spin-coating a hole transport layer with a thickness of 0.5 nm on top of the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazole-9-yl) ethyl] phosphonic acid.
[0058] (3) dissolving 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255)3); 15 mg of anhydrous cesium carbonate (small molecule swelling agent) is then added to 1 mL of the perovskite precursor solution, which is stirred at room temperature for more than 4 h until the perovskite precursor is completely dissolved to obtain a small molecule perovskite precursor solution; the small molecule perovskite precursor solution is then spin-coated on the electron transport layer, and a perovskite layer with a thickness of 600 nm is obtained after heat treatment.
[0059] (4) An electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm are sequentially evaporated above the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0060] Embodiment B3: A preparation method of a perovskite solar cell, comprising the following steps: (1) ITO glass is used as a substrate.
[0061] (2) A hole transport layer with a thickness of 0.5 nm is spin-coated above the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazol-9-yl) ethyl] phosphoric acid.
[0062] (3) 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 are dissolved in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255 )3); 15 mg of anhydrous cesium carbonate (small molecule swelling agent) is then added to 1 mL of the perovskite precursor solution, which is stirred at room temperature for more than 4 h until the perovskite precursor is completely dissolved to obtain a small molecule perovskite precursor solution; the small molecule perovskite precursor solution is then spin-coated on the electron transport layer, and a perovskite layer with a thickness of 600 nm is obtained after heat treatment.
[0063] (4) An electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm are sequentially evaporated above the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0064] Embodiment C1: A preparation method of a perovskite solar cell, comprising the following steps: (1) ITO glass is used as a substrate.
[0065] (2) spin-coating a hole transport layer with a thickness of 0.5 nm on top of the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazole-9-yl)ethyl]phosphonic acid.
[0066] (3) dissolving 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255 )3) with a concentration of 1.5 mol / L; then adding 5 mg of acridine (a small-molecule swelling agent) into 1 mL of the perovskite precursor solution, stirring for more than 4 h at room temperature until the perovskite precursor is completely dissolved to obtain a small-molecule perovskite precursor solution; and spin-coating the small-molecule perovskite precursor solution on the electron transport layer to obtain a perovskite layer with a thickness of 600 nm after heat treatment.
[0067] (4) sequentially evaporating an electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm on top of the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0068] Embodiment C2: A method for preparing a perovskite solar cell, comprising the following steps: (1) using ITO glass as a substrate.
[0069] (2) spin-coating a hole transport layer with a thickness of 0.5 nm on top of the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazole-9-yl)ethyl]phosphonic acid.
[0070] (3) dissolving 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255)3); 15 mg of acridine (a small molecule swelling agent) was then added to 1 mL of the perovskite precursor solution, which was stirred at room temperature for more than 4 h until the perovskite precursor was completely dissolved to obtain a small molecule perovskite precursor solution; the small molecule perovskite precursor solution was then spin-coated on the electron transport layer, and a perovskite layer with a thickness of 600 nm was obtained after heat treatment.
[0071] (4) An electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm were sequentially evaporated above the perovskite layer; in this embodiment, the material of the electron transport layer was C60, and the material of the electrode layer was Ag.
[0072] Example C3: A preparation method of a perovskite solar cell, comprising the following steps: (1) ITO glass was used as a substrate.
[0073] (2) A hole transport layer with a thickness of 0.5 nm was spin-coated above the substrate; in this embodiment, the material of the hole transport layer was [2-(9H-carbazol-9-yl) ethyl] phosphoric acid.
[0074] (3) 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 were dissolved in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255 )3); 15 mg of acridine (a small molecule swelling agent) was then added to 1 mL of the perovskite precursor solution, which was stirred at room temperature for more than 4 h until the perovskite precursor was completely dissolved to obtain a small molecule perovskite precursor solution; the small molecule perovskite precursor solution was then spin-coated on the electron transport layer, and a perovskite layer with a thickness of 600 nm was obtained after heat treatment.
[0075] (4) An electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm were sequentially evaporated above the perovskite layer; in this embodiment, the material of the electron transport layer was C60, and the material of the electrode layer was Ag.
[0076] Comparative Example D1: A preparation method of a perovskite solar cell, comprising the following steps: (1) ITO glass was used as a substrate.
[0077] (2) spin-coating a hole transport layer with a thickness of 0.5 nm above the substrate; in this embodiment, the material of the hole transport layer is [2-(9H-carbazole-9-yl) ethyl] phosphonic acid.
[0078] (3) dissolving 219.26 mg of FAI, 16.80 mg of MABr, 19.49 mg of CsI, 522.09 mg of PbI2, and 140.38 mg of PbBr2 in an organic solvent composed of 0.8 mL of DMF and 0.2 mL of DMSO to obtain a perovskite precursor solution (Cs 0.05 FA 0.85 MA 0.1 Pb(I 0.755 Br 0.255 )3) with a concentration of 1.5 mol / L, stirring for more than 4 h at room temperature until the perovskite precursor is completely dissolved to obtain a completely dissolved perovskite precursor solution; then spin-coating the completely dissolved perovskite precursor solution on the electron transport layer, and obtaining a perovskite layer with a thickness of 600 nm after heat treatment.
[0079] (4) sequentially evaporating an electron transport layer with a thickness of 20 nm and an electrode layer with a thickness of 100 nm above the perovskite layer; in this embodiment, the material of the electron transport layer is C60, and the material of the electrode layer is Ag.
[0080] The perovskite cells are prepared through the above embodiments and comparative examples, and the performance of the prepared perovskite cells is tested, and the performance test results of the perovskite cells are shown in Table 1.
[0081] Table 1: Performance test results of perovskite cells It can be seen from the results in Table 1 that the performance of the perovskite cell is improved after adding an appropriate amount of small molecule swelling agent, but excessive small molecule swelling agent will reduce the performance, because excessive small molecule swelling agent will increase the crystallization of the perovskite layer too fast or too large, thereby affecting its performance. And from Figure 3 it can be seen that the thermal stability of the perovskite cell is obviously improved after adding the small molecule swelling agent Figure 3 the comparison in Table 1 only lists the highest efficiency cell in each embodiment and comparative example.
[0082] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A perovskite solar cell, characterized by, The perovskite solar cell is from bottom to top a substrate, a hole transport layer, a perovskite layer, an electron transport layer and an electrode layer; or the perovskite solar cell is from bottom to top a substrate, an electron transport layer, a perovskite layer, a hole transport layer and an electrode layer.
2. A method for preparing a perovskite solar cell, characterized by, The method comprises the following steps: (1) using ITO glass as a substrate; (2) spin-coating a hole transport layer with a thickness of 0.5-10 nm on the substrate; (3) dissolving perovskite precursors in an organic solvent to obtain a perovskite precursor solution with a concentration of 1.5 mol / L; Then 5-15 mg of a small-molecule swelling agent is added to 1 mL of the perovskite precursor solution, and stirring is performed until the perovskite precursors are completely dissolved, to obtain a small-molecule perovskite precursor solution; Then the small-molecule perovskite precursor solution is spin-coated on the hole transport layer, and a perovskite layer with a thickness of 100-1000 nm is obtained after heat treatment; (4) sequentially evaporating an electron transport layer and an electrode layer with a thickness of 5-50 nm on the perovskite layer; Or (1) using ITO glass as a substrate; (2) evaporating an electron transport layer with a thickness of 5-50 nm on the substrate; (3) dissolving perovskite precursors in an organic solvent to obtain a perovskite precursor solution with a concentration of 1.5 mol / L; Then 5-15 mg of a small-molecule swelling agent is added to 1 mL of the perovskite precursor solution, and stirring is performed until the perovskite precursors are completely dissolved, to obtain a small-molecule perovskite precursor solution; Then the small-molecule perovskite precursor solution is spin-coated on the hole transport layer, and a perovskite layer with a thickness of 100-1000 nm is obtained after heat treatment; (4) spin-coating a hole transport layer with a thickness of 0.5-10 nm on the perovskite layer; (5) then evaporating an electrode layer on the hole transport layer.
3. The method for preparing a perovskite solar cell according to claim 2, characterized in that, The material of the hole transport layer is a self-assembled molecular layer material containing a phosphoric acid group.
4. The method of claim 3, wherein the perovskite solar cell is prepared by the steps of: The self-assembled molecular layer material containing a phosphoric acid group is one or more of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid and [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid.
5. The method for preparing a perovskite solar cell according to claim 2, characterized in that, The perovskite precursor is ABX3, wherein A is a cation comprising one or more of CH3NH3 + , HC(NH2)2 + , and Cs + ; B is a metal ion comprising one or more of Pb 2+ , Sn 2+ , and Sr 2+ ; and X is a halogen ion comprising one or more of Br - , I - , and Cl - .
6. The method for preparing a perovskite solar cell according to claim 2, characterized in that, The small-molecule swelling agent is a small-molecule organic compound, an inorganic small molecule or a functional small molecule.
7. The method for preparing a perovskite solar cell according to claim 6, characterized in that, The small-molecule organic compound includes but is not limited to benzimidazole small molecules, furan small molecules and polymer small molecules; the inorganic small molecule includes but is not limited to cesium salts or lithium salts; the functional small molecule includes but is not limited to nitrogen heterocyclic compounds or carbon heterocyclic compounds.
8. The method for preparing a perovskite solar cell according to claim 2, characterized in that, The material of the electron transport layer is one or more of fullerene or fullerene derivatives.
9. The method for preparing a perovskite solar cell according to claim 2, characterized in that, The material of the electrode layer is one or more of gold, silver, copper and aluminum.