Perovskite solution, perovskite absorption layer, perovskite solar cell, preparation method and photovoltaic module

Abstract

The application relates to the technical field of solar cells, in particular to a perovskite solution, a perovskite absorption layer, a perovskite solar cell, a preparation method and a photovoltaic module. The perovskite solution provided by the application comprises a conductive material, and the conductivity of the perovskite solution is 0.001 S / m-2 S / m. The perovskite solution provided by the application can actively and accurately fly to a conductive substrate along the direction of an electric force line under the condition of being driven by a strong coulomb force, so that a directional adsorption effect is formed, and a high-quality perovskite thin film with a large area and uniform thickness is obtained.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and in particular to a perovskite solution, a perovskite absorber layer, a perovskite solar cell, a method for preparing the perovskite solar cell, and a photovoltaic module. Background Technology

[0002] Organic-inorganic hybrid perovskite materials possess advantages such as high absorption coefficients, tunable band gaps, long carrier diffusion lengths, and high defect tolerance. Furthermore, they offer advantages like simple fabrication processes and low manufacturing costs, making perovskite materials considered the most commercially viable new material in the photovoltaic market in recent years. After only a decade or so of research, single-junction perovskite solar cells have achieved high photoelectric conversion efficiencies, surpassing commercially available cadmium telluride and copper indium gallium selenide (CIGS) cells and approaching the 26.7% photoelectric conversion efficiency of mainstream crystalline silicon solar cells. Perovskite tandem solar cells combine high efficiency and low cost, and are considered one of the technologies with the potential for large-scale ground-mounted photovoltaic applications. With their outstanding advantages of high efficiency, low cost, and simple fabrication processes, perovskite tandem solar cells have gradually become a hot topic in global photovoltaic research in recent years. In the process of industrialization, the ability to rapidly fabricate large-area, uniformly thick, high-quality perovskite thin films is crucial. Currently, large-area perovskite thin film fabrication mainly employs slot coating technology, although inkjet printing and electrostatic spraying methods are also used to fabricate large-area perovskite thin films.

[0003] When fabricating perovskite solar cell devices, slit coating technology struggles to completely cover the substrate edges, leading to efficiency losses. Furthermore, the slit coating process is lengthy and slow, making it incompatible with large-area mass production processes. Inkjet printing technology, on the other hand, suffers from the problem of large particles in the perovskite solution clogging pores, affecting the long-term stable use of the equipment and also proving incompatible with the large-scale fabrication of large-area perovskite thin films. When preparing large-area perovskite films using electrostatic spraying technology, the quality of perovskite films obtained by slot coating cannot yet be achieved. Currently, the solvents used in perovskite solutions are typically N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and N-methylpyrrolidone (NMP). These solvents are highly polar, have good solubility for ABX3 type perovskite, and possess strong coordination ability, preventing reactions with ligands. Their evaporation rate is controllable, which can improve the stability of the perovskite solution. However, these solvents have extremely low conductivity, resulting in good insulation of the perovskite solution during electrostatic spraying. This prevents charge transfer to the perovskite droplets, thus hindering electrostatic adsorption. If the conductivity of the perovskite solution is increased too much, the charge will be instantly lost, again preventing it from becoming charged and potentially posing a safety hazard. Therefore, providing a safe perovskite solution with suitable conductivity is a major technical problem that needs to be solved.

[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Summary of the Invention

[0005] This application provides a perovskite solution, a perovskite absorber layer, a perovskite solar cell, a preparation method thereof, and a photovoltaic module to solve the technical problem of having a perovskite solution with both safety and suitable conductivity.

[0006] The first aspect of this application provides a perovskite solution comprising a conductive material, wherein the conductivity of the perovskite solution is 0.001 S / m to 2 S / m.

[0007] The perovskite solution provided in this application includes a conductive material, and the conductivity of the perovskite solution is controlled to be 0.001 S / m-2 S / m.

[0008] When using electrostatic spraying, droplets of perovskite solution can be driven by strong Coulomb force to actively and precisely fly towards the conductive substrate along the direction of electric field lines, forming a directional adsorption effect. This method is safe, eliminates safety hazards, and can produce high-quality perovskite films with large area and uniform thickness.

[0009] Optionally, the conductive material includes at least one of conductive liquid, conductive polymer, liquid crystal molecules, carbon nanomaterials, or small molecule electrolytes.

[0010] The conductive material used in this application includes at least one of conductive liquid, conductive polymer, liquid crystal molecules, carbon nanomaterials, or small molecule electrolytes, which can make the conductivity of the perovskite solution reach 0.001S / m-2S / m. It can be sprayed into a film using an electrostatic spraying method, and it is safe, eliminating safety hazards. It can obtain a large area and uniform thickness of high-quality perovskite thin film.

[0011] Optionally, the conductive liquid comprises water or a mixed solution of water and a C1-C4 aliphatic compound containing hydroxyl or carbonyl groups; wherein, in the mixed solution, the water content is 20-500 ppm; And / or, the volume ratio of water to perovskite solution is (0.2-5):10000; And / or, the volume ratio of the C1-C4 aliphatic compound containing hydroxyl or carbonyl groups to the perovskite solution is 1:(8-25). The C1-C4 aliphatic compounds containing hydroxyl or carbonyl groups include at least one of methanol, ethanol, isopropanol, ethylene glycol, glycerol, or acetone.

[0012] In this embodiment, the volume ratio of water to perovskite solution is (0.2-5):10000. During the experiment, it was found that when the amount of water is within this range, it will not affect the film formation and crystallization of the perovskite solution, and can improve the photoelectric conversion efficiency and stability of solar cell devices.

[0013] This application embodiment uses a volume ratio of hydroxyl- or carbonyl-containing C1-C4 aliphatic compounds to perovskite solution of 1:(8-25). The hydroxyl- or carbonyl-containing C1-C4 aliphatic compounds include at least one selected from methanol, ethanol, isopropanol, ethylene glycol, glycerol, or acetone. A mixed solution is formed between water and the hydroxyl- or carbonyl-containing C1-C4 aliphatic compounds; wherein the water content in the mixed solution is 20-500 ppm. Experiments have shown that within this range, the conductivity of the perovskite solution can be improved without affecting its solubility. Electrostatic spraying can be used for film formation, which is safe, eliminates safety hazards, and allows for the acquisition of high-quality perovskite films with large areas and uniform thickness.

[0014] Optionally, the conductive polymer includes at least one of thiophene polymer, polyvinylidene fluoride, or polyvinyl alcohol.

[0015] Optionally, the mass-volume concentration of the conductive polymer in the perovskite solution is 0.5 mg / mL to 2 mg / mL; wherein the water content in the perovskite solution is 20-500 ppm.

[0016] The embodiments of this application use a conductive polymer including at least one of thiophene polymer, polyvinylidene fluoride, or polyvinyl alcohol, and the mass-volume concentration of the conductive polymer in the perovskite solution is 0.5 mg / mL-2 mg / mL. In the perovskite solution, when the water content is 20-500 ppm, it was found in the experiment that the amount of conductive polymer used in this range does not damage the conductivity of the perovskite crystal structure. The film can be formed by electrostatic spraying, which is safe, eliminates safety hazards, and can obtain a high-quality perovskite film with a large area and uniform thickness.

[0017] Optionally, the liquid crystal molecules include at least one of the following: rod-shaped liquid crystals of cyanobiphenyl type, cholesteric liquid crystals of cholesterol ester derivative type, disc-shaped liquid crystals mainly composed of benzo[a]phenanthrene, hexabenzo[a]carbamate, and phthalocyanine type, and curved liquid crystals with resorcinol and oxadiazole ring as the core framework.

[0018] Optionally, the mass-volume concentration of the liquid crystal molecules in the perovskite solution is 0.1 mg / mL to 1 mg / mL.

[0019] In this embodiment, the mass-volume concentration of liquid crystal molecules in the perovskite solution is 0.1 mg / mL to 1 mg / mL. During the experiment, it was found that when the amount of liquid crystal molecules is within this range, it will not damage the conductivity of the perovskite crystal structure. Electrostatic spraying can be used to form a film, which is safe and eliminates safety hazards. It can obtain a large area and uniform thickness of high-quality perovskite film.

[0020] Optionally, the carbon nanomaterial includes graphene.

[0021] Optionally, the mass-volume concentration of the carbon nanomaterial in the perovskite solution is 0.1 mg / mL to 1 mg / mL.

[0022] Optionally, the small molecule electrolyte includes at least one of the following: hexafluorophosphate, tetrafluoroborate, sulfonate, carbonate, bicarbonate, sulfide, sulfate, thiosulfate, hypophosphite, or phosphate containing lithium, sodium, potassium, rubidium, cesium, imidazole, methylamine, or formamidinium.

[0023] Optionally, the mass-volume concentration of the small molecule electrolyte in the perovskite solution is 0.5 mg / mL to 10 mg / mL.

[0024] In this application embodiment, the mass-volume concentration of small molecule electrolyte in the perovskite solution is 0.5 mg / mL-10 mg / mL. During the experiment, it was found that when the amount of small molecule electrolyte is within this range, it will not damage the perovskite crystal structure. Electrostatic spraying can be used to spray the film, which is safe and eliminates safety hazards. It can obtain a large area and uniform thickness of high-quality perovskite film.

[0025] A second aspect of this application provides a perovskite absorber layer prepared from a perovskite solution as described above.

[0026] The third aspect of this application provides a method for preparing a perovskite absorber layer, wherein the perovskite solution described above is electrostatically sprayed onto a battery substrate to form a perovskite thin film; and the perovskite thin film is then heated and annealed to obtain a perovskite absorber layer.

[0027] In this embodiment, a perovskite solution with a conductivity of 0.001 S / m-2 S / m is electrostatically sprayed onto a battery substrate to form a perovskite thin film. This achieves the effects of safety, high efficiency, low cost, and simple process, and can obtain a large area and uniform thickness of high-quality perovskite thin film.

[0028] The fourth aspect of this application provides a perovskite solar cell, including the perovskite absorber layer as described above or the perovskite absorber layer prepared by the method described above.

[0029] The perovskite solar cell provided in this application has a high-quality perovskite absorber layer with uniform thickness and large area, which can promote the industrialization of perovskite solar cells.

[0030] The fifth aspect of this application provides a method for fabricating a perovskite solar cell, comprising: The perovskite solution described above is electrostatically sprayed onto a battery substrate to form a perovskite film; the perovskite film is then heated and annealed to obtain a perovskite absorber layer.

[0031] The perovskite solar cell fabrication method provided in this application adopts an electrostatic spraying method, which sprays a perovskite solution with a conductivity of 0.001S / m-2S / m onto the cell substrate. This achieves the effects of safety, high efficiency, low cost and simple process, and can obtain a large area and uniform thickness of high-quality perovskite thin film, which can promote the industrialization of perovskite solar cells.

[0032] The sixth aspect of this application provides a photovoltaic module, including a perovskite solar cell as described above or a perovskite solar cell prepared by the method described above.

[0033] The embodiments of this application employing the above-described technical solution may have the following advantages: The perovskite solution provided in this application includes conductive materials, and the conductivity of the perovskite solution is controlled to be 0.001 S / m-2 S / m. When using the electrostatic spraying method, the droplets of the perovskite solution can be driven by a strong Coulomb force to actively and precisely fly towards the conductive substrate along the direction of the electric field lines, forming a directional adsorption effect. It is also safe, eliminating the safety hazards when the perovskite solution has high conductivity, and can obtain high-quality perovskite films with large area and uniform thickness.

[0034] The perovskite absorber layer preparation method provided in this application adopts an electrostatic spraying method. The perovskite solution with a conductivity of 0.001S / m-2S / m as described above is sprayed onto the battery substrate by electrostatic spraying, which achieves the effects of safety, high efficiency, low cost and simple process, and can obtain a large area and uniform thickness of high-quality perovskite film.

[0035] The perovskite solar cell provided in this application has a high-quality perovskite absorber layer with uniform thickness and large area, which can promote the industrialization of perovskite solar cells.

[0036] The perovskite solar cell fabrication method provided in this application employs electrostatic spraying to coat a perovskite solution with a conductivity of 0.001 S / m-2 S / m onto a cell substrate. This method achieves safety, high efficiency, low cost, and a simple process, and can obtain high-quality perovskite films with large area and uniform thickness. This improves the photoelectric conversion efficiency and stability of perovskite solar cell devices and can promote the industrialization of perovskite solar cells. Attached Figure Description

[0037] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0038] Figure 1 This is a schematic diagram of the structure of a solar cell provided in an embodiment of this application.

[0039] Figure 2 This is a schematic diagram of the process of applying a solution using an electrostatic spraying system.

[0040] Explanation of reference numerals in the attached figures: Figure 1 The structure includes an n-type silicon substrate 100, a first intrinsic amorphous silicon layer 110, a second intrinsic amorphous silicon layer 120, an n-type microcrystalline silicon layer 130, a p-type microcrystalline silicon layer 140, a transparent electrode 150, a back electrode 160, a tunneling layer 200, a hole transport layer 300, a perovskite absorption layer 310, a passivation layer 320, an electron transport layer 330, a buffer layer 340, a transparent conductive layer 350, an anti-reflection layer 360, and a top electrode 370. Detailed Implementation

[0041] The embodiments of this application are described in detail below, examples of which are illustrated in the accompanying drawings. In the drawings, for clarity, the dimensions of layers, regions, and elements, as well as their relative dimensions, may be exaggerated. Throughout, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. It should be noted that, unless otherwise specified, the features of this application and its embodiments can be combined with each other.

[0042] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this application, the first element, component, area, layer, or portion discussed below may be referred to as a second element, component, area, layer, or portion. And the discussion of a second element, component, area, layer, or portion does not imply that the first element, component, area, layer, or portion necessarily exists in this application.

[0043] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0044] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0045] This application involves numerical intervals (i.e., numerical ranges). Unless otherwise specified, the distribution of selectable numerical values ​​within a 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 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 percentage intervals, ratio intervals, proportion intervals, etc.

[0046] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. It should be understood that these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0047] This application provides a perovskite solution comprising a conductive material, wherein the conductivity of the perovskite solution is 0.001 S / m-2 S / m.

[0048] The perovskite solution provided in this application includes conductive materials, and the conductivity of the perovskite solution is controlled to be 0.001 S / m-2 S / m. When using the electrostatic spraying method, the droplets of the perovskite solution can be driven by a strong Coulomb force to actively and accurately fly towards the conductive substrate along the electric field lines, forming a directional adsorption effect. This method is safe, eliminates safety hazards, and can obtain a high-quality perovskite film with a large area and uniform thickness.

[0049] In optional embodiments, the conductive material includes at least one of conductive liquid, conductive polymer, liquid crystal molecules, carbon nanomaterials, or small molecule electrolytes.

[0050] The conductive material used in this application includes at least one of conductive liquid, conductive polymer, liquid crystal molecules, carbon nanomaterials or small molecule electrolytes, which can make the conductivity of the perovskite solution reach 0.001S / m-2S / m. When using the electrostatic spraying method, a high-quality perovskite film with a large area and uniform thickness can be obtained.

[0051] In an optional embodiment, the conductive liquid comprises water or a mixed solution of water and a C1-C4 aliphatic compound containing hydroxyl or carbonyl groups; wherein, in the mixed solution, the water content is 20-500 ppm (exemplary values ​​such as 20 ppm, 30 ppm, 40 ppm, 50 ppm, 60 ppm, 70 ppm, 80 ppm, 90 ppm, 100 ppm, 120 ppm, 150 ppm, 180 ppm, 200 ppm, 230 ppm, 250 ppm, 280 ppm, 300 ppm, 330 ppm, 350 ppm, 380 ppm, 400 ppm, 420 ppm, 450 ppm, 480 ppm, etc.). In optional embodiments, the volume ratio of water to perovskite solution is (0.2-5):10000 (exemplary ratios include 0.2:10000, 0.5:10000, 0.8:10000, 1:10000, 1.2:10000, 1.5:10000, 1.8:10000, 2:10000, 2.2:10000, 2.5:10000, 2.8:10000, 3:10000, 3.2:10000, 3.5:10000, 3.8:10000, 4:10000, 4.2:10000, 4.5:10000, 4.8:10000, 5:10000, etc.).

[0052] In an optional embodiment, the volume ratio of the C1-C4 aliphatic compound containing hydroxyl or carbonyl groups to the perovskite solution is 1:(8-25) (exemplary examples include 1:8, 1:10, 1:12, 1:15, 1:18, 1:20, 1:22, 1:25, etc.).

[0053] In optional embodiments, the C1-C4 aliphatic compound containing hydroxyl or carbonyl groups includes at least one of methanol, ethanol, isopropanol, ethylene glycol, glycerol, or acetone.

[0054] In this embodiment, the volume ratio of water to perovskite solution is (0.2-5):10000. During the experiment, it was found that when the amount of water is within this range, it will not affect the film formation and crystallization of the perovskite solution, and can improve the photoelectric conversion efficiency and stability of solar cell devices.

[0055] This application embodiment uses a volume ratio of hydroxyl- or carbonyl-containing C1-C4 aliphatic compounds to perovskite solution of 1:(8-25). The hydroxyl- or carbonyl-containing C1-C4 aliphatic compounds include at least one selected from methanol, ethanol, isopropanol, ethylene glycol, glycerol, or acetone. A mixed solution is formed between water and the hydroxyl- or carbonyl-containing C1-C4 aliphatic compounds; wherein the water content in the mixed solution is 20-500 ppm. Experiments have shown that within this range, the conductivity of the perovskite solution can be improved without affecting its solubility. Electrostatic spraying can be used for film formation, which is safe, eliminates safety hazards, and allows for the acquisition of high-quality perovskite films with large areas and uniform thickness.

[0056] In an optional embodiment, the conductive polymer includes at least one of thiophene polymer, polyvinylidene fluoride, or polyvinyl alcohol.

[0057] In an optional embodiment, the mass-volume concentration of the conductive polymer in the perovskite solution is 0.5 mg / mL to 2 mg / mL (exemplary values ​​include 0.5 mg / mL, 0.8 mg / mL, 1 mg / mL, 1.2 mg / mL, 1.5 mg / mL, 1.8 mg / mL, 2 mg / mL, etc.); wherein, in the perovskite solution, the water content is 20-500 ppm (exemplary values ​​include 20 ppm, 30 ppm, 40 ppm, 50 ppm, 60 ppm, 70 ppm, 80 ppm, 90 ppm, 100 ppm, 120 ppm, 150 ppm, 180 ppm, 200 ppm, 230 ppm, 250 ppm, 280 ppm, 300 ppm, 330 ppm, 350 ppm, 380 ppm, 400 ppm, 420 ppm, 450 ppm, 480 ppm, 500 ppm, etc.).

[0058] The embodiments of this application use a conductive polymer including at least one of thiophene polymer, polyvinylidene fluoride, or polyvinyl alcohol, and the mass-volume concentration of the conductive polymer in the perovskite solution is 0.5 mg / mL-2 mg / mL. In the perovskite solution, when the water content is 20-500 ppm, it was found in the experiment that the amount of conductive polymer used in this range does not damage the conductivity of the perovskite crystal structure. The film can be formed by electrostatic spraying, which is safe, eliminates safety hazards, and can obtain a high-quality perovskite film with a large area and uniform thickness.

[0059] In optional embodiments, the liquid crystal molecules include at least one of the following: rod-shaped liquid crystals of cyanobiphenyl type, cholesteric liquid crystals of cholesterol ester derivative type, disc-shaped liquid crystals mainly composed of benzo[a]phenanthrene, hexabenzo[a]methyl phthalocyanine, and phthalocyanine type, and tortuous liquid crystals with resorcinol and oxadiazole ring as the core skeleton; the mass-volume concentration of the liquid crystal molecules in the perovskite solution is 0.1 mg / mL-1 mg / mL (exemplary values ​​such as 0.1 mg / mL, 0.2 mg / mL, 0.3 mg / mL, 0.4 mg / mL, 0.5 mg / mL, 0.6 mg / mL, 0.7 mg / mL, 0.8 mg / mL, 0.9 mg / mL, 1 mg / mL, etc.).

[0060] In this embodiment, the mass-volume concentration of liquid crystal molecules in the perovskite solution is 0.1 mg / mL to 1 mg / mL. During the experiment, it was found that when the amount of liquid crystal molecules is within this range, it will not damage the conductivity of the perovskite crystal structure. Electrostatic spraying can be used to form a film, which is safe and eliminates safety hazards. It can obtain a large area and uniform thickness of high-quality perovskite film.

[0061] In an optional embodiment, the carbon nanomaterial includes graphene; the mass-volume concentration of the carbon nanomaterial in the perovskite solution is 0.1 mg / mL to 1 mg / mL (exemplary values ​​include 0.1 mg / mL, 0.2 mg / mL, 0.3 mg / mL, 0.4 mg / mL, 0.5 mg / mL, 0.6 mg / mL, 0.7 mg / mL, 0.8 mg / mL, 0.9 mg / mL, 1 mg / mL, etc.).

[0062] In this embodiment, the mass-volume concentration of carbon nanomaterials in the perovskite solution is 0.1 mg / mL to 1 mg / mL. During the experiment, it was found that when the amount of carbon nanomaterials is within this range, it does not damage the conductivity of the perovskite crystal structure and can improve the photoelectric conversion efficiency and stability of the perovskite solar cell device.

[0063] In an optional embodiment, the small molecule electrolyte comprises at least one of the following: hexafluorophosphate, tetrafluoroborate, sulfonate, carbonate, bicarbonate, sulfide, sulfate, thiosulfate, hypophosphite, or phosphate containing lithium, sodium, potassium, rubidium, cesium, imidazole, methylamine, or formamidinium; the mass-volume concentration of the small molecule electrolyte in the perovskite solution is 0.5 mg / mL to 10 mg / mL.

[0064] In this embodiment, the mass-volume concentration of the small molecule electrolyte in the perovskite solution is 0.5 mg / mL-10 mg / mL. During the experiment, it was found that when the amount of small molecule electrolyte is within this range, it will not damage the perovskite crystal structure. Electrostatic spraying can be used to form a film, which is safe and eliminates safety hazards. It can obtain a large area and uniform thickness of high-quality perovskite film.

[0065] This application provides a perovskite absorber layer prepared from a perovskite solution as described above.

[0066] This application provides a method for preparing a perovskite absorber layer, comprising the following steps: electrostatically spraying the perovskite solution as described above onto a battery substrate to form a perovskite thin film; and annealing the perovskite thin film to obtain a perovskite absorber layer.

[0067] In an optional embodiment, the method for preparing the perovskite absorber layer includes the following steps: In an optional embodiment, the perovskite solution described above is sprayed onto the battery substrate using an electrospray system to obtain a perovskite film.

[0068] This application employs an electrostatic spraying method to electrostatically spray a perovskite solution with a conductivity of 0.001 S / m-2 S / m onto a battery substrate to form a perovskite thin film. This method achieves the effects of safety, high efficiency, low cost, and simple process, and can obtain high-quality perovskite thin films with large area and uniform thickness.

[0069] This application provides a perovskite solar cell, including the perovskite absorber layer as described above or the perovskite absorber layer prepared by the method described above.

[0070] This application provides a method for fabricating a perovskite solar cell, comprising: The perovskite solution described above is electrostatically sprayed onto a battery substrate to form a perovskite film; the perovskite film is then heated and annealed to obtain a perovskite absorber layer.

[0071] In an optional embodiment, the perovskite solution described above is sprayed onto the battery substrate using an electrospray system to obtain a perovskite film.

[0072] This application employs an electrostatic spraying method to spray a perovskite solution with a conductivity of 0.001 S / m-2 S / m onto a battery substrate. This achieves a safe, high-efficiency, low-cost, and simple process, and can obtain a large-area, uniformly thick, high-quality perovskite film. This improves the photoelectric conversion efficiency and stability of perovskite solar cell devices and can promote the industrialization of perovskite solar cells.

[0073] In an optional embodiment, the perovskite solar cell includes a perovskite / crystalline silicon tandem solar cell.

[0074] This application provides a method for fabricating a perovskite / crystalline silicon tandem solar cell, comprising the following steps: S1. Fabrication of crystalline silicon bottom solar cells: S11. Using a chemical vapor deposition process, amorphous silicon (a-Si(i)) is deposited on the first and second surfaces on both sides of an n-type silicon wafer substrate at a deposition temperature of 180-210℃ (exemplary, such as 180℃, 190℃, 200℃, 205℃, 210℃, etc.) to obtain a first intrinsic amorphous silicon layer with a thickness of 5-10nm (exemplary, such as 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, etc.) and a second intrinsic amorphous silicon layer with a thickness of 5-10nm (exemplary, such as 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, etc.); S12. Using a chemical vapor deposition process, p-type microcrystalline silicon is deposited on the surface of the second intrinsic amorphous silicon layer at a deposition temperature of 180-210℃ (exemplary, such as 180℃, 190℃, 200℃, 205℃, 210℃, etc.) to obtain a p-type microcrystalline silicon layer with a thickness of 2-8nm (exemplary, such as 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, etc.); S13. Using a chemical vapor deposition process, n-type microcrystalline silicon is deposited on the surface of the first intrinsic amorphous silicon layer at a deposition temperature of 180-210℃ (exemplary, such as 180℃, 190℃, 200℃, 205℃, 210℃, etc.) to obtain an n-type microcrystalline silicon layer with a thickness of 2-8nm (exemplary, such as 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, etc.); S14. Using physical vapor deposition, ITO (indium tin oxide) is deposited on the surface of a p-type microcrystalline silicon layer at a deposition temperature of 70-90℃ (exemplary, such as 70℃, 75℃, 80℃, 85℃, 90℃, etc.) to obtain a bottom transparent electrode with a thickness of 60-100nm (exemplary, such as 60nm, 70nm, 80nm, 90nm, 100nm, etc.); S15. Using physical vapor deposition, Ag is deposited on the surface of the bottom transparent electrode at a deposition temperature of 80-110℃ (exemplary, such as 80℃, 90℃, 100℃, 105℃, 110℃, etc.) to obtain a bottom back electrode with a thickness of 2-10nm (exemplary, such as 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, etc.); S2. Preparation of tunneling layer: Using physical vapor deposition, IZO (indium zinc oxide) is deposited on the surface of the n-type microcrystalline silicon layer of the crystalline silicon bottom cell at a deposition temperature of 70-90℃ (exemplary, such as 70℃, 75℃, 80℃, 85℃, 90℃, etc.) to obtain a tunneling layer with a thickness of 10-20nm (exemplary, such as 10nm, 12nm, 15nm, 18nm, 20nm, etc.); S3. Fabrication of perovskite top solar cells: S31. Dissolve [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid in ethanol to prepare a [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid solution with a molar concentration of 0.2-2 mmol / L (exemplary, such as 0.2 mmol / L, 0.5 mmol / L, 0.8 mmol / L, 1.2 mmol / L, 1.5 mmol / L, 2 mmol / L, etc.). Take 80-120 μL (exemplary, such as 80 μL, 90 μL, 100 μL, 110 μL, 120 μL, etc.) of the [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid solution and drop it onto the surface of the tunneling layer obtained on the surface of the n-type microcrystalline silicon layer of the crystalline silicon bottom cell, at 3000-5000 rpm (exemplary, such as 3...). Spin-coating at rotation speeds of 000 rpm, 3500 rpm, 4000 rpm, 4500 rpm, 5000 rpm, etc. for 5-20 seconds (exemplary values ​​such as 5 seconds, 8 seconds, 10 seconds, 12 seconds, 15 seconds, 18 seconds, 20 seconds, etc.) and then annealing on a heating stage at a temperature of 80-120℃ (exemplary values ​​such as 80℃, 90℃, 100℃, 105℃, 110℃, 115℃, 120℃, etc.) for 5-15 minutes (exemplary values ​​such as 5 minutes, 7 minutes, 10 minutes, 12 minutes, 15 minutes, etc.) to obtain a hole transport layer with a thickness of 1-30 nm (exemplary values ​​such as 1 nm, 2 nm, 3 nm, 5 nm, 8 nm, 10 nm, 12 nm, 15 nm, 18 nm, 20 nm, 23 nm, 25 nm, 28 nm, 30 nm, etc.). S32. 85-90 mg (exemplary, such as 85 mg, 86 mg, 87 mg, 88 mg, 88.3 mg, 89 mg, 90 mg, etc.) of cesium iodide, 225-240 mg (exemplary, such as 225 mg, 227 mg, 229 mg, 230 mg, 232 mg, 233.3 mg, 235 mg, 238 mg, 240 mg, etc.) of formamidinium iodoformide, 185-190 mg (exemplary, such as 185 mg, 186 mg, 187 mg, 187.2 mg, 188 mg, 189 mg, 190 mg, etc.) of lead bromide, and 540-550 mg (exemplary, such as 540 mg, 90 mg, etc.) of formamidinium iodoformide. Lead iodide (mg, 542mg, 544mg, 546mg, 548mg, 548.6mg, 550mg, etc.) is dissolved in a mixed solvent of DMF and DMSO (the volume ratio of DMF to DMSO is (3-5):1 (exemplary, such as 3:1, 4:1, 5:1, etc.)). The solution is then filtered through a 0.1-0.5μm (exemplary, such as 0.1μm, 0.22μm, 0.4μm, 0.5μm, etc.) PTFE filter to obtain a FA molar concentration of 1-2mol / L (exemplary, such as 1mol / L, 1.2mol / L, 1.5mol / L, 1.8mol / L, 2mol / L, etc.). 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. Add conductive material to the perovskite solution; use an electrostatic spraying method to spray the perovskite solution with conductive liquid added onto the surface of the hole transport layer through an electrospray system, and deposit a perovskite film on the surface of the hole transport layer. Place the perovskite film on a heating stage at a temperature of 110-130℃ (exemplary, such as 110℃, 115℃, 120℃, 125℃, 130℃, etc.) for annealing for 10-25 min (exemplary, such as 10 min, 12 min, 15 min). The perovskite absorber layer with a thickness of 0.5-1.5 μm was obtained by performing processes such as 18 min, 20 min, 22 min, and 25 min. In this embodiment, a crystalline silicon bottom cell is used. The n-type silicon wafer used in the crystalline silicon bottom cell undergoes texturing, which forms a pyramid structure at the microscopic level, and has a certain impact on the subsequent layer structure. The perovskite absorber layer obtained in this embodiment has a non-uniform thickness and has a range of thickness, ranging from 0.5 to 1.5 μm.

[0075] The crystalline silicon bottom cell that obtains the hole transport layer in S31 is placed on the receiving plate of the electrospray system. The distance between the receiving plate and the nozzle of the electrospray system is 55-65mm (exemplary values ​​such as 55mm, 56mm, 57mm, 58mm, 59mm, 60mm, 61mm, 62mm, 63mm, 64mm, 65mm, etc.). The voltage of the electrospray system is set to 15-30 kV (exemplary values ​​such as 15 kV, 18 kV, 20 kV, 25 kV, 28 kV, 30 kV, etc.), and the propulsion speed is 0.001-0.005mm / min (exemplary values ​​such as 0.001mm / min, 0.002mm / min, 0.003mm / min, 0.004mm / min, 0.005mm / min, etc.). The propulsion speed is the speed at which the piston in the injector of the electrospray system advances when pumping liquid forward.

[0076] S33. Dissolve 2-phenylethylamine hydroiodate and oleylamine iodine in isopropanol at a molar ratio of 3-5:1 (exemplary, such as 3:1, 4:1, 5:1, etc.) to prepare a passivation solution with a mass-volume concentration of 0.5-1.5 mg / mL (exemplary, such as 0.5 mg / mL, 0.8 mg / mL, 1 mg / mL, 1.2 mg / mL, 1.5 mg / mL, etc.). Place the passivation solution on the surface of the perovskite absorber layer and apply it at 3000-5000 rpm (exemplary, such as 3000 rpm, 3500 rpm, 400 rpm, etc.). Spin coat at a rotation speed of 0 rpm, 4500 rpm, 5000 rpm, etc. for 8-15 seconds (exemplary, such as 8 seconds, 10 seconds, 12 seconds, 15 seconds, etc.), then place it on a heating stage at a temperature of 80-110℃ (exemplary, such as 80℃, 90℃, 100℃, 105℃, 110℃, etc.) for 2-8 minutes (exemplary, such as 2 minutes, 4 minutes, 6 minutes, 8 minutes, etc.) to obtain a passivation layer with a thickness of 5-10 nm (exemplary, such as 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, etc.). S34. Fullerene (C60) is deposited on the surface of the passivation layer by thermal evaporation to obtain a fullerene electron transport layer with a thickness of 10-20 nm (exemplary, such as 10 nm, 12 nm, 15 nm, 18 nm, 20 nm, etc.). S35. Atomic layer deposition is used to deposit tin dioxide on the surface of the fullerene electron transport layer to obtain a tin dioxide buffer layer with a thickness of 8-20 nm (exemplary, such as 8 nm, 10 nm, 13 nm, 15 nm, 18 nm, 20 nm, etc.); S36. IZO is deposited on the surface of the tin dioxide buffer layer using physical vapor deposition to obtain a top transparent conductive layer with a thickness of 50-90 nm (exemplary, such as 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, etc.); S37. Magnesium fluoride is deposited on the surface of the top transparent conductive layer by thermal evaporation to obtain an anti-reflective layer with a thickness of 100-200 nm (exemplary, such as 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, 160 nm, 170 nm, 180 nm, 190 nm, 200 nm, etc.); S38. Silver is deposited on the surface of the anti-reflective layer using a thermal evaporation method to obtain a silver gate line with a thickness of 600-1000nm (exemplary, such as 600nm, 700nm, 800nm, 900nm, 1000nm, etc.) as the top electrode.

[0077] This application provides a photovoltaic module, including a perovskite solar cell as described above or a perovskite solar cell prepared by the method described above.

[0078] The following section will present performance tests on the structure or fabrication method of the perovskite solar cell provided in the embodiments of this application, as well as related comparative examples.

[0079]

Example 1

[0080] The crystalline silicon bottom cell includes an n-type microcrystalline silicon layer 130, a first intrinsic amorphous silicon layer 110, an n-type silicon wafer substrate 100, a second intrinsic amorphous silicon layer 120, a p-type microcrystalline silicon layer 140, a transparent electrode 150, and a back electrode 160, which are stacked sequentially.

[0081] The perovskite top solar cell comprises, in sequence, a hole transport layer 300, a perovskite absorption layer 310, a passivation layer 320, an electron transport layer 330, a buffer layer 340, a transparent conductive layer 350, an anti-reflection layer 360, and a top electrode 370.

[0082] This application provides a method for fabricating a perovskite / crystalline silicon tandem solar cell, comprising the following steps: S1. Fabrication of crystalline silicon bottom solar cells: S11. Using chemical vapor deposition, amorphous silicon (a-Si(i)) is deposited on the first and second surfaces of an n-type silicon substrate 100 with a thickness of 150 μm at a deposition temperature of 200 °C, to obtain a first intrinsic amorphous silicon layer 110 with a thickness of 8 nm and a second intrinsic amorphous silicon layer 120 with a thickness of 8 nm. S12. Using chemical vapor deposition, p-type microcrystalline silicon is deposited on the surface of the second intrinsic amorphous silicon layer at a deposition temperature of 200℃ to obtain a p-type microcrystalline silicon layer 140 with a thickness of 6nm. S13. Using chemical vapor deposition, n-type microcrystalline silicon is deposited on the surface of the first intrinsic amorphous silicon layer at a deposition temperature of 200℃ to obtain an n-type microcrystalline silicon layer 130 with a thickness of 6nm. S14. Using physical vapor deposition, ITO (indium tin oxide) is deposited on the surface of a p-type microcrystalline silicon layer at a deposition temperature of 80℃ to obtain a bottom transparent electrode 150 with a thickness of 80nm. S15. Using physical vapor deposition, Ag is deposited on the surface of the bottom transparent electrode at a deposition temperature of 100℃ to obtain a bottom back electrode 160 with a thickness of 4nm. S2. Preparation of tunneling layer: IZO (indium zinc oxide) was deposited on the surface of the n-type microcrystalline silicon layer of the crystalline silicon bottom cell using physical vapor deposition at a deposition temperature of 80℃ to obtain a tunneling layer 200 with a thickness of 15nm. S3. Fabrication of perovskite top solar cells: S31. Dissolve [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid in ethanol to prepare a [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid solution with a molar concentration of 0.8 mmol / L. Take 100 μL of the [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid solution and drop it onto the surface of the tunneling layer obtained on the surface of the n-type microcrystalline silicon layer of the crystalline silicon bottom cell. Spin coat it at 4000 rpm for 12 s, and then place it on a heating stage at 100℃ for annealing for 10 min to obtain a hole transport layer 300 with a thickness of 1-3 nm. S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.23. A perovskite solution is prepared, and a conductive material, water, is added to the perovskite solution. The volume ratio of water to perovskite solution is 1:10000. An electrostatic spraying method is used to spray the perovskite solution with the added conductive material onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 minutes to obtain a perovskite absorber layer 310 with a thickness of 0.5-1.5 μm. The crystalline silicon bottom cell that obtains the hole transport layer in S31 is placed on the receiving board of the electrospray system. The distance between the receiving board and the nozzle of the electrospray system is 60mm. The voltage of the electrospray system is set to 20 kV and the propulsion speed is 0.001mm / min. S33. Dissolve 2-phenylethylamine hydroiodide and oleylamine iodide in isopropanol at a molar ratio of 4:1 to prepare a passivation solution with a mass-volume concentration of 0.8 mg / mL. Place 60 μL of the passivation solution on the surface of the perovskite absorber layer and spin coat it at 4000 rpm for 12 s. Then place it on a heating stage at 100℃ for annealing for 4 min to obtain a passivation layer 320 with a thickness of 5-10 nm. S34. Fullerene (C60) is deposited on the surface of the passivation layer by thermal evaporation to obtain a fullerene electron transport layer 330 with a thickness of 12 nm. S35. Tin dioxide was deposited on the surface of the fullerene electron transport layer by atomic layer deposition to obtain a tin dioxide buffer layer 340 with a thickness of 10 nm. S36. IZO was deposited on the surface of the tin dioxide buffer layer by physical vapor deposition to obtain a top transparent conductive layer 350 with a thickness of 70 nm. S37. Magnesium fluoride is deposited on the surface of the top transparent conductive layer by thermal evaporation to obtain an anti-reflection layer 360 with a thickness of 120 nm; S38. Silver is deposited on the surface of the antireflective layer by thermal evaporation to obtain a silver gate line with a thickness of 800 nm as the top electrode 370.

[0083] like Figure 2 The diagram shows a process of applying a solution using an electrostatic spraying system.

[0084]

Example 2

[0085] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. After filtration, obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. A perovskite solution is prepared, and a conductive material is added to the perovskite solution. The conductive material is a mixed solution of methanol and water with a water content of 300 ppm and a volume ratio of 1:20 between the mixed solution and the perovskite solution. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorption layer with a thickness of 0.5-1.5 μm.

[0086]

Example 3

[0087] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. A perovskite solution is prepared, and a conductive material is added to the perovskite solution. The conductive material is a mixed solution of glycerol and water, with a water content of 300 ppm and a volume ratio of 1:10 between the mixed solution and the perovskite solution. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorption layer with a thickness of 0.5-1.5 μm.

[0088]

Example 4

[0089] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. A perovskite solution is prepared, and a conductive material, polyvinyl alcohol, is added to the perovskite solution. The mass-volume concentration of polyvinyl alcohol in the perovskite solution is 1 mg / mL. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorption layer with a thickness of 0.5-1.5 μm.

[0090]

Example 5

[0091] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.23. A perovskite solution is prepared, and a conductive material, benzo[a]phenanthrene-1,5,9-triamine hydroiodate, is added to the perovskite solution. The mass-volume concentration of benzo[a]phenanthrene-1,5,9-triamine hydroiodate in the perovskite solution is 0.3 mg / mL. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorber layer with a thickness of 0.5-1.5 μm.

[0092] The benzophenanthrene-1,5,9-triamine hydroiodide is obtained by acid-base neutralization reaction of benzophenanthrene-1,5,9-triamine and hydroiodic acid, wherein the molar ratio of benzophenanthrene-1,5,9-triamine to hydroiodic acid is 1:3.2.

[0093]

Example 6

[0094] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. A perovskite solution is prepared, and a conductive material, namely graphene oxide, is added to the perovskite solution. The mass-volume concentration of graphene oxide in the perovskite solution is 0.5 mg / mL. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is placed on a heating stage at a temperature of 120°C and annealed for 20 min to obtain a perovskite absorption layer with a thickness of 0.5-1.5 μm.

[0095]

Example 7

[0096] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. A perovskite solution is prepared, and a conductive material, lithium tetrafluoroborate, is added to the perovskite solution. The mass-volume concentration of lithium tetrafluoroborate in the perovskite solution is 1 mg / mL. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorber layer with a thickness of 0.5-1.5 μm.

[0097]

Example 8

[0098] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.23. A perovskite solution is prepared, and a conductive material, rubidium hexafluorophosphate, is added to the perovskite solution. The mass-volume concentration of rubidium hexafluorophosphate in the perovskite solution is 6 mg / mL. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorption layer with a thickness of 0.5-1.5 μm.

[0099]

Example 9

[0100] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. A perovskite solution is prepared, and a conductive material, cesium methanesulfonate, is added to the perovskite solution. The mass-volume concentration of cesium methanesulfonate in the perovskite solution is 2 mg / mL. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorption layer with a thickness of 0.5-1.5 μm.

[0101]

Example 10

[0102] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. A perovskite solution is prepared, and a conductive material is added to the perovskite solution. The conductive material is water and ammonium carbonate, with a volume ratio of water to perovskite solution of 3:10000 and a mass-volume concentration of ammonium carbonate in the perovskite solution of 4 mg / mL. An electrostatic spraying method is used to spray the perovskite solution with the added conductive liquid onto the surface of the hole transport layer through an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 min to obtain a perovskite absorption layer with a thickness of 0.5-1.5 μm.

[0103] In Examples 1-10 of this application, when adding conductive materials to the perovskite solution, the conductivity of the perovskite solution can be adjusted by adding a small amount of water in order to make the conductivity of the perovskite solution between 0.001 S / m and 2 S / m.

[0104] Comparative Example 1 A perovskite / crystalline silicon tandem solar cell of Comparative Example 1 was prepared according to the preparation method of the perovskite / crystalline silicon tandem solar cell provided in Example 1, except that no conductive material was added to the perovskite solution in step S32.

[0105] The details are as follows: S32. Dissolve 88.3 mg cesium iodide, 233.9 mg formamidine iodide, 187.2 mg lead bromide, and 548.6 mg lead iodide in a mixed solvent of 800 μL DMF and 200 μL DMSO. Filter the solution through a 0.22 μm PTFE filter to obtain FA with a molar concentration of 1.7 mol / L. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 3. Perovskite solution: The perovskite solution is sprayed onto the surface of the hole transport layer using an electrospray system, and a perovskite film is deposited on the surface of the hole transport layer. The perovskite film is then annealed on a heating stage at 120°C for 20 minutes to obtain a perovskite absorber layer with a thickness of 0.5-1.5 μm.

[0106] Performance testing Regarding the fabrication methods of perovskite / crystalline silicon tandem solar cells provided in Examples 1-10 and Comparative Example 1 of this application, the conductivity of the perovskite solution sprayed by the electrospray system was tested using the CV cyclic voltammetry method, and the test results are shown in Table 1.

[0107] The perovskite / crystalline silicon tandem solar cells provided in Examples 1-10 and Comparative Example 1 of this application were tested under standard test conditions to obtain the open-circuit voltage Voc, fill factor FF, short-circuit current density Jsc, and photoelectric conversion efficiency PCE of the corresponding perovskite / crystalline silicon tandem solar cells. The test results are shown in Table 1.

[0108] The fill factor (FF) used in this paper refers to the ratio of the actual maximum obtainable power (Pm or Vmp × Jmp) to the theoretical (not actually obtainable) power (Jsc × Voc). Therefore, FF can be determined by the following formula: FF = (Vmp × Jmp) / (Jsc × Voc), Where Jmp and Vmp represent the current density and voltage at the maximum power point (Pm), respectively, this point is obtained by changing the resistance in the circuit until J×V reaches its maximum value; Jsc and Voc represent the short-circuit current and open-circuit voltage, respectively. The fill factor is a key parameter for evaluating solar cells. Commercial solar cells typically have a fill factor of approximately 60% or higher.

[0109] The open-circuit voltage (Voc) used in this paper is the potential difference between the anode and cathode of the device under conditions of no external load connection.

[0110] The short-circuit current (Isc) used in this article is the maximum current flowing through the output terminal of a photovoltaic cell or module when it is short-circuited (voltage V=0) under STC conditions.

[0111] The power conversion efficiency (PCE) of solar cells used in this article refers to the percentage of power converted from absorbed light into electrical energy, expressed as a percentage (%). The PCE of a solar cell can be measured under standard test conditions (STC) based on incident light irradiance (E: W / m²). 2 ) and the surface area of ​​solar cells (Ac:m 2 The STC is calculated by dividing by the point of maximum power (Pm). STC typically refers to the value at a temperature of 25°C and an irradiance of 100 W / m². 2 The spectrum of air quality 1.5 (AM1.5).

[0112] Table 1 provides test data for the perovskite / crystalline silicon tandem solar cells provided in Examples 1-10 and Comparative Example 1.

[0113] Table 1

[0114] As shown in Table 1 above, in Examples 1-10, the addition of conductive materials to the perovskite solution increased the conductivity of the perovskite solution to 0.001-2 S / m. The addition of conductive materials improved the photoelectric conversion efficiency (PCE) of the obtained perovskite / crystalline silicon tandem solar cells, resulting in a PCE exceeding 32%, an open-circuit voltage greater than 1.9 V, and a fill factor of 79.46%-82.52%. In contrast, in Comparative Example 1, no conductive materials were added to the perovskite solution, and the conductivity of the perovskite solution was 2 × 10⁻⁶. -5 The perovskite / crystalline silicon tandem solar cell prepared in Comparative Example 1 has a low photoelectric conversion efficiency (PCE) of 27.4% and a fill factor of 75.3%.

[0115] In summary, the perovskite solution provided in this application can be sprayed onto the battery substrate using an electrostatic spraying method to obtain a high-quality perovskite thin film, thereby further improving the photoelectric conversion efficiency and stability of perovskite solar cell devices.

[0116] This application embodiment can also provide a photovoltaic module (not shown), which includes the perovskite solar cell described above. The perovskite solar cell can be connected in series and / or in parallel with one or more other solar cells in a predetermined manner. Multiple cells can form a cell string, and adjacent cells can be connected together by string welding.

[0117] It should be noted that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. The directional terms "inner" and "outer" refer to the inside or outside relative to the outline of the component itself. For example, if a device in the drawings is inverted, a device described as "above" or "on top of" other devices or structures will subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0118] It should also be noted that, in this application, the terms "one embodiment," "another embodiment," or "embodiment," etc., refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0119] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0120] It should also be noted that the above are merely preferred embodiments of this application and do not limit the scope of patent protection of this application. Any equivalent structural or procedural changes made using the content of this application’s specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A perovskite solution, characterized in that, The perovskite solution includes a conductive material, and the conductivity of the perovskite solution is 0.001 S / m - 2 S / m.

2. The perovskite solution according to claim 1, characterized in that, The conductive material includes at least one of conductive liquid, conductive polymer, liquid crystal molecules, carbon nanomaterials, or small molecule electrolytes.

3. The perovskite solution according to claim 2, characterized in that, The conductive liquid comprises water or a mixed solution of water and a C1-C4 aliphatic compound containing hydroxyl or carbonyl groups; wherein the water content in the mixed solution is 20-500 ppm. And / or, the volume ratio of water to perovskite solution is (0.2-5):10000; And / or, the volume ratio of the C1-C4 aliphatic compound containing hydroxyl or carbonyl groups to the perovskite solution is 1:(8-25). The C1-C4 aliphatic compounds containing hydroxyl or carbonyl groups include at least one of methanol, ethanol, isopropanol, ethylene glycol, glycerol, or acetone.

4. The perovskite solution according to claim 2, characterized in that, The conductive polymer includes at least one of thiophene polymer, polyvinylidene fluoride, or polyvinyl alcohol. And / or, the mass-volume concentration of the conductive polymer in the perovskite solution is 0.5 mg / mL to 2 mg / mL; The water content in the perovskite solution is 20-500 ppm.

5. The perovskite solution according to claim 2, characterized in that, The liquid crystal molecules include at least one of the following: rod-shaped liquid crystals of cyanobiphenyl type, cholesteric liquid crystals of cholesterol ester derivative type, disc-shaped liquid crystals mainly composed of benzophenanthrene, hexabenzo[a]methyl phthalocyanine, and phthalocyanine type; and curved liquid crystals with resorcinol and oxadiazole ring as the core framework. And / or, the mass-volume concentration of the liquid crystal molecules in the perovskite solution is 0.1 mg / mL to 1 mg / mL.

6. The perovskite solution according to claim 2, characterized in that, The carbon nanomaterials include graphene; the mass-volume concentration of the carbon nanomaterials in the perovskite solution is 0.1 mg / mL to 1 mg / mL.

7. The perovskite solution according to claim 2, characterized in that, The small molecule electrolyte includes at least one of the following: hexafluorophosphate, tetrafluoroborate, sulfonate, carbonate, bicarbonate, sulfide, sulfate, thiosulfate, hypophosphite, or phosphate containing lithium, sodium, potassium, rubidium, cesium, imidazole, methylamine, or formamidinium; and / or, The mass-volume concentration of the small molecule electrolyte in the perovskite solution is 0.5 mg / mL to 10 mg / mL.

8. A perovskite absorber layer, characterized in that, It is prepared from a perovskite solution comprising any one of claims 1-7.

9. A method for preparing a perovskite absorber layer, characterized in that, Includes the following steps: The perovskite solution according to any one of claims 1-7 is electrostatically sprayed onto the battery substrate to form a perovskite thin film. After the perovskite film is heated and annealed, a perovskite absorber layer is obtained.

10. A perovskite solar cell, characterized in that, The perovskite absorber layer includes the perovskite absorber layer as described in claim 8 or the perovskite absorber layer prepared by the method described in claim 9.

11. A method for fabricating a perovskite solar cell, characterized in that, Includes the following steps: The perovskite solution according to any one of claims 1-7 is electrostatically sprayed onto the battery substrate to form a perovskite film. After the perovskite film is heated and annealed, a perovskite absorber layer is obtained.

12. A photovoltaic module, characterized in that, This includes perovskite solar cells prepared by the method described in claim 10 or claim 11.

Images