Solar cell and preparation method therefor, and electrical device

Abstract

Disclosed in the present application are a solar cell and a preparation method therefor, and an electrical device. The solar cell comprises a light absorption layer, an interlayer and an electron transport layer, wherein the interlayer is located between the light absorption layer and the electron transport layer; and the interlayer comprises a polymer, the molecular weight of the polymer being greater than 10 kg / mol. By means of providing an interlayer between a light absorption layer and an electron transport layer, a reaction between the electron transport layer and the light absorption layer can be blocked, and defects on the surface of the light absorption layer can also be passivated, thereby reducing stray reflections, preventing the recombination of photon-generated carriers, and improving the efficiency of photoelectric conversion.

Description

Solar cell and its preparation method, and electrical equipment Technical Field

[0001] The present application relates to the field of new energy technology, and in particular to solar cells, preparation methods thereof, and electrical equipment. Background Art

[0002] Currently, the global economy faces challenges such as resource shortages, environmental pollution, and a harsh climate. The development and utilization of clean energy is crucial. Developing new energy materials and devices meets the needs of current national development and can effectively address the environmental challenges associated with the use of fossil fuels.

[0003] Solar cells have attracted widespread attention due to their ability to directly convert sunlight into electrical energy without causing environmental pollution. They can be used in a variety of fields, including military, aerospace, industry, commerce, agriculture, and communications.

[0004] The photoelectric conversion efficiency of solar cells affects the promotion and application of solar cells.

[0005] Summary of the Invention

[0006] The main technical problem solved by this application is to provide a solar cell and a preparation method thereof, and electrical equipment to improve the light conversion efficiency of the solar cell.

[0007] In order to solve the above technical problems, the first aspect of the present application provides a solar cell, including a light absorption layer, an intercalation layer and an electron transport layer, wherein the intercalation layer is located between the light absorption layer and the electron transport layer; the intercalation layer includes a polymer, and the molecular weight of the polymer is greater than 10 kg / mol.

[0008] By setting an intercalation layer between the light absorption layer and the electron transport layer, the intercalation layer includes a polymer with a molecular weight greater than 10kg / mol. The intercalation layer can block the reaction between the electron transport layer and the light absorption layer and maintain the stability of the light absorption layer. The intercalation layer can also passivate the defects on the surface of the light absorption layer. The intercalation layer fills the holes and defects on the surface of the light absorption layer, reduces stray reflections, blocks the recombination of photogenerated carriers, and improves the photoelectric conversion efficiency.

[0009] In one embodiment, the polymer includes one or more of polymethyl methacrylate, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polyethylene vinyl acetate, polyacrylonitrile, linear polyethyleneimine, and branched polyethyleneimine, which can achieve good barrier and passivation effects.

[0010] In one embodiment, the intercalation layer further comprises fullerenes and their derivatives. Fullerenes and their derivatives regulate energy levels, improving the energy level matching between the light-absorbing layer and the electron-transporting layer, forming efficient electron transport channels, and thereby increasing device efficiency and photoelectric conversion efficiency. In other words, in addition to the intercalation layer comprising a polymer, the inclusion of fullerenes and their derivatives further enhances photoelectric conversion efficiency.

[0011] In one embodiment, fullerenes and their derivatives include one or more of fullerene C60 (C60), fullerene C70 (C70), [6,6]-phenyl-C61-butyric acid methyl ester, [6,6]-phenyl-C71-butyric acid methyl ester, and indene-C60 bisadduct. The selection of these materials improves the energy level matching between the light absorption layer and the electron transport layer, forming an efficient electron transport channel, preventing electron and hole recombination, and improving photoelectric conversion efficiency.

[0012] In one embodiment, the fullerene and its derivatives include [6,6]-phenyl-C61-butadienedicarboxylic acid dibutyl ester. 61 BM has excellent electron transport properties and high charge mobility; PC 61 BM can be used to promote the transport and collection of electrons, thus, through PC 61 BM can form an efficient electron transmission channel, which can effectively prevent the recombination of photogenerated electrons and holes, improve the efficiency of semiconductor devices, and improve the photoelectric conversion efficiency. 61 The BM makes the energy levels between the light absorption layer 11 and the electron transport layer 13 more matched, forms an efficient electron transport channel, prevents the recombination of electrons and holes, and improves the photoelectric conversion efficiency.

[0013] In one embodiment, the mass ratio of the polymer to the fullerene and its derivatives in the intercalated layer is 1%-10%, achieving a better barrier effect and a better passivation effect.

[0014] In one embodiment, the thickness of the intercalation layer is 2nm-10nm; optionally, the thickness of the intercalation layer is 3nm-7nm, which achieves better barrier effect and better passivation effect, and improves photoelectric conversion efficiency.

[0015] In one embodiment, the electron transport layer comprises an atomic layer deposited oxide; optionally, the oxide comprises one or more of tin oxide, aluminum oxide, and zinc oxide. Atomic layer deposition of oxides can form an extremely thin and dense film, which not only facilitates electron transport but also blocks the light absorption layer from external substances such as water and oxygen, significantly improving device stability and performance.

[0016] In one embodiment, the light absorbing layer includes a perovskite material; optionally, the perovskite material includes a halide perovskite. Perovskite has a photoelectric conversion function. Perovskite absorbs photons from sunlight to generate excitation, which excites electrons in the valence band to generate photogenerated holes and electron pairs.

[0017] In one embodiment, the solar cell has an inverted structure, and an intercalation layer is provided between the light absorbing layer and the electron transport layer, thereby achieving a higher photoelectric conversion efficiency.

[0018] In one embodiment, the solar cell further comprises a first electrode layer, a second electrode layer, and a hole transport layer. The hole transport layer is disposed on a side of the light absorbing layer away from the electron transport layer. The first electrode layer is disposed on a side of the hole transport layer away from the light absorbing layer, and the second electrode layer is disposed on a side of the electron transport layer away from the intercalation layer. Optionally, the solar cell further comprises a passivation layer disposed between the light absorbing layer and the hole transport layer. The passivation layer fills holes and defects on the surface of the light absorbing layer near the hole transport layer, reduces stray reflections, and prevents recombination of photogenerated carriers, thereby improving photoelectric conversion efficiency.

[0019] To solve the above technical problems, the second aspect of the present application provides a method for preparing a solar cell, comprising: providing an intercalation layer slurry, the intercalation layer slurry including a polymer, the molecular weight of the polymer being greater than 10 kg / mol; and forming an intercalation layer on the side of the light absorption layer close to the electron transport layer.

[0020] By forming an intercalation layer between the light absorption layer and the electron transport layer, the intercalation layer includes a polymer with a molecular weight greater than 10kg / mol. The intercalation layer can block the reaction between the electron transport layer and the light absorption layer and maintain the stability of the light absorption layer. The intercalation layer can also passivate defects on the surface of the light absorption layer. The intercalation layer fills the holes and defects on the surface of the light absorption layer, reduces stray reflections, blocks the recombination of photogenerated carriers, and improves the photoelectric conversion efficiency.

[0021] In one embodiment, the polymer includes one or more of polymethyl methacrylate, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polyethylene vinyl acetate, polyacrylonitrile, linear polyethyleneimine, and branched polyethyleneimine, which can achieve good barrier and passivation effects.

[0022] In one embodiment, the concentration of the polymer in the interpenetrating layer slurry is in the range of 0.5 mg / mL to 2.0 mg / mL, so as to form a thinner and denser membrane layer.

[0023] In one embodiment, the intercalation layer slurry includes a polymer and fullerenes and their derivatives; the concentration range of fullerenes and their derivatives is 10 mg / mL-20 mg / mL. Optionally, the mass ratio of polymer to fullerenes and their derivatives is 1%-10%, so as to form a thinner and denser film layer and significantly improve the photoelectric conversion efficiency.

[0024] In one embodiment, the solvent for the intercalating layer slurry includes one or more of chlorobenzene, dichloromethane, and chloroform, which have good solubility and result in a more uniform and dense film. Optionally, the solvent for the intercalating layer slurry is dichloromethane:chlorobenzene in a volume ratio of (0-2):1. These solvents are applicable regardless of whether the intercalating layer slurry comprises a polymer or a polymer and fullerenes and their derivatives. When the intercalating layer slurry comprises a polymer and fullerenes and their derivatives, the use of these solvents allows for the preparation of the fullerene and their derivative layer and polymer passivation in a single step, simplifying the process and reducing costs. The solvents also have good solubility in the polymer and fullerenes and their derivatives, resulting in a more uniform mixing of the two and a more uniform and dense film.

[0025] To solve the above technical problems, the third aspect of the present application provides an electrical device, comprising the solar cell of the first aspect or the solar cell produced by the method for producing a solar cell of the second aspect. The electrical device has at least the same advantages as the solar cell.

[0026] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0028] FIG1 is a schematic structural diagram of a solar cell provided in an embodiment of the present application;

[0029] FIG2 is a schematic flow chart of a method for preparing a solar cell provided in an embodiment of the present application.

[0030] In the attached figure:

[0031] 11 - light absorption layer; 12 - intercalation layer; 13 - electron transport layer; 14 - first electrode layer; 15 - second electrode layer; 16 - hole transport layer; 17 - base layer; 18 - passivation layer. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and effect of this application clearer and more specific, the following embodiments of the technical solution of this application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of this application and are therefore only examples and are not intended to limit the scope of protection of this application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0034] In the description of the embodiments of the present application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), similarly, "multiple groups" refers to more than two (including two), and "multiple pieces" refers to more than two (including two), unless otherwise clearly and specifically defined.

[0035] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0036] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0037] Amounts, ratios, and other numerical values ​​are presented herein in a range format. It should be understood that such range format is used for convenience and brevity and should be interpreted flexibly to include not only the values ​​explicitly specified as range limits, but also all individual values ​​or sub-ranges encompassed within the range, as if each value and sub-range were explicitly specified.

[0038] Unless otherwise specified, all steps of the present application may be performed sequentially, randomly, or in parallel, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially, or may include steps (a) and (b) performed simultaneously in parallel. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b), and (c), or may include steps (a), (c), and (b), or may include steps (c), (a), and (b), etc.

[0039] Solar cells have attracted widespread attention due to their ability to directly convert sunlight into electrical energy without causing environmental pollution. They can be used in a variety of fields, including military, aerospace, industry, commerce, agriculture, and communications.

[0040] Perovskite solar cells have gradually become a hot topic in the research of the next generation of solar cells due to their advantages such as high photoelectric conversion efficiency, simple manufacturing process, low production cost and material cost. However, the photoelectric conversion efficiency of perovskite solar cells affects the promotion and application of perovskite solar cells.

[0041] Based on this, the present application provides a solar cell and a preparation method thereof, and an electrical device to improve the photoelectric conversion efficiency of the solar cell.

[0042] Please refer to FIG1 , which is a schematic structural diagram of a solar cell provided in an embodiment of the present application.

[0043] The solar cell provided in an embodiment of the present application includes a light absorbing layer 11, an intercalating layer 12 and an electron transport layer 13 stacked in sequence. The intercalating layer 12 is located between the light absorbing layer 11 and the electron transport layer 13. The intercalating layer 12 is used to block the reaction between the material of the electron transport layer and the material of the light absorbing layer 11. The intercalating layer 12 includes a polymer; the molecular weight of the polymer is greater than 10 kg / mol. Optionally, the polymer includes one or more of polymethyl methacrylate (PMMA), polyvinyl alcohol (PEO), polyvinyl pyrrolidone (PVP), polyacrylic acid (PAA), polyethylene vinyl acetate (PEVA), polyacrylonitrile (PAN), linear polyethyleneimine (L-PEI), and branched polyethyleneimine (B-PEI).

[0044] The molecular structure of PMMA is:

[0045] The molecular structure of PEO is:

[0046] The molecular structure of PVP is:

[0047] The molecular structure of PAA is:

[0048] The molecular structure of PEVA is:

[0049] The molecular structure of PAN is:

[0050] The molecular structure of L-PEI is:

[0051] The molecular structure of B-PEI is:

[0052] The light absorption layer 11 is used to absorb light and directly convert light energy into electrical energy through the photoelectric effect or photochemical effect. The light absorption layer 11 includes a light-absorbing material with a photoelectric conversion function. The light-absorbing material absorbs photons from sunlight to generate excitation, which excites electrons in the valence band to produce photogenerated holes and electron pairs. The electron transport layer 13 functions to efficiently transport free electrons generated by the light absorption layer 11, effectively blocking the passage of free holes, and forming an ohmic contact at the interface with the light absorption layer 11.

[0053] In one embodiment, the material of the light absorbing layer 11 includes, but is not limited to, perovskite (PVK) materials. Perovskite has a photoelectric conversion function. The chemical formula of perovskite is ABX3, where A is an inorganic cation and / or an organic cation, B is an inorganic cation and / or an organic cation, and X is an inorganic anion and / or an organic anion.

[0054] Wherein, A is an inorganic cation, or an organic cation, or a mixture of an inorganic cation and an organic cation. Optionally, A is a methylamino group (CH3NH3 + )(MA + ), carbamimidyl (HC(NH2)2 + )(FA + ), cesium ions (Cs + ) and rubidium (Rb + ) at least one of.

[0055] B is an inorganic cation, an organic cation, or a mixture of an inorganic cation and an organic cation. Optionally, B is a divalent metal ion Pb 2+ and Sn 2+ At least one of .

[0056] X is an inorganic anion, an organic anion, or a mixture of an inorganic anion and an organic anion. Optionally, X is a halogen anion; that is, the perovskite material includes a halide perovskite.

[0057] Exemplarily, the perovskite material includes at least one of MAPbI3 and FAPbI3.

[0058] In one embodiment, the material of the electron transport layer 13 includes oxide, which can form a protective layer to prevent water and oxygen from corroding the light absorption layer 11, thereby improving the stability and life of the device.

[0059] Optionally, the oxide includes one or more of tin oxide, aluminum oxide, and zinc oxide, which are cheap and readily available, thereby helping to reduce the cost of the device.

[0060] Optionally, the electron transport layer 13 includes an atomic layer deposition oxide, that is, an oxide is deposited by atomic layer deposition (ALD). By atomic layer deposition of oxide, an extremely thin and dense film can be formed, which significantly improves the stability and performance of the device; especially in high temperature and high humidity environments, the stability and performance of the device can be significantly improved. It should be noted that the formation process of the oxide (that is, the electron transport layer 13) is not limited to atomic layer deposition, and oxide preparation processes such as sol method, chemical sintering method, electron beam evaporation method, etc. can also be used, and the specific design is based on the needs.

[0061] In one embodiment, the solar cell has a trans structure. When the light absorbing layer 11 includes a perovskite material and the material of the electron transport layer 13 includes an oxide, in the preparation process of the solar cell, the light absorbing layer 11 is first formed, and the electron transport layer 13 is formed on one side of the light absorbing layer 11. The electron transport layer 13 is formed by atomic layer deposition of oxide. If the atomic layer deposition of oxide is performed directly on the surface of the light absorbing layer 11, the atomic layer deposition of oxide will react with the perovskite to generate a layer of electron isolation layer to block electron transmission, causing device failure. The embodiment of the present application forms an intercalation layer 12 between the light absorbing layer 11 and the electron transport layer 13; in the preparation process of the solar cell, the light absorbing layer 11 is first formed, the intercalation layer 12 is formed on the surface of the light absorbing layer 11, and then the electron transport layer 13 is formed on the surface of the intercalation layer 12 away from the light absorbing layer 11, so that the electron transport layer 13 (atomic layer deposition oxide) is not directly prepared on the surface of the light absorbing layer 11, thereby improving the device failure caused by directly using atomic layer deposition of oxide on the perovskite.

[0062] In one embodiment, the solar cell has a formal structure; during the preparation process of the solar cell, an electron transport layer 13 is first formed, an intercalation layer 12 is formed on the surface of the electron transport layer 13, and then a light absorption layer 11 is formed on the surface of the intercalation layer 12 away from the electron transport layer 13.

[0063] By providing the above-mentioned intercalation layer 12 between the light absorbing layer 11 and the electron transport layer 13, the intercalation layer 12 plays a role in protecting the light absorbing layer 11 and preventing the light absorbing layer 11 from being destroyed by the external environment (for example, water and oxygen); the intercalation layer 12 can block the reaction between the electron transport layer 13 and the light absorbing layer 11, and maintain the stability of the light absorbing layer 11; the intercalation layer 12 can also passivate the defects on the surface of the light absorbing layer 11, and the intercalation layer 12 fills the holes and defects on the surface of the light absorbing layer 11, thereby reducing stray reflections, blocking the recombination of photogenerated carriers, and improving the photoelectric conversion efficiency.

[0064] In one embodiment, the intercalation layer 12 comprises a polymer and fullerenes and their derivatives. Fullerenes and their derivatives regulate energy levels, improving the energy level match between the light absorbing layer 11 and the electron transport layer 13, forming an efficient electron transport channel, improving device efficiency, and simultaneously increasing photoelectric conversion efficiency. In other words, in addition to the intercalation layer 12 comprising a polymer, the inclusion of fullerenes and their derivatives further improves photoelectric conversion efficiency.

[0065] Optionally, fullerene and its derivatives include fullerene C60 (C60), fullerene C70 (C70), [6,6]-phenyl-C61-butyric acid methyl ester (PC 61 BM), [6,6]-phenyl-C71-butyric acid methyl ester (PC 71 The use of these materials allows for a better match between the energy levels of the light absorbing layer and the electron transport layer, forming an efficient electron transport channel, preventing electron and hole recombination, and improving photoelectric conversion efficiency.

[0066] Optionally, fullerene and its derivatives include [6,6]-phenyl-C61-butadienedicarboxylic acid dibutyl ester (PC 61 BM). PC 61 BM has excellent electron transport properties and high charge mobility; PC 61 BM can be used to promote the transport and collection of electrons, thus, through PC 61 BM can form an efficient electron transmission channel, which can effectively prevent the recombination of photogenerated electrons and holes, improve the efficiency of semiconductor devices, and improve the photoelectric conversion efficiency. 61 The BM makes the energy levels between the light absorption layer 11 and the electron transport layer 13 more matched, forms an efficient electron transport channel, prevents the recombination of electrons and holes, and improves the photoelectric conversion efficiency.

[0067] Optionally, the mass ratio of the polymer to fullerene and its derivatives in the intercalation layer 12 is 1%-10%, achieving a good barrier effect (blocking the reaction between the electron transport layer 13 and the light absorbing layer 11) and a good passivation effect (passivating defects on the surface of the light absorbing layer 11). The resulting intercalation layer 12 has a low resistance and a small impact on the current. Exemplarily, the mass ratio of the polymer to fullerene and its derivatives in the intercalation layer 12 can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., or a range consisting of any two of the above values, for example, 3%-4%, 6%-7%, 7%-10%, etc.

[0068] In one embodiment, the intercalation layer 12 further includes alcohol additives to improve wettability and device performance.

[0069] Optionally, the alcohol additive may be at least one of ethanol and isopropanol.

[0070] In one embodiment, the thickness of the intercalation layer 12 is 2nm-10nm, which can achieve both a blocking and a passivation effect. Furthermore, although the polymer included in the intercalation layer 12 is generally a non-conductor, the thickness of the intercalation layer 12 is designed as described above to have a minimal impact on the current flow, thereby improving the photoelectric conversion efficiency. Alternatively, the thickness of the intercalation layer 12 is 3nm-7nm, which can achieve both a blocking and a passivation effect while maintaining a high photoelectric conversion efficiency. Exemplarily, the thickness of the intercalation layer 12 can be 3nm, 3.5nm, 4nm, 4.5nm, 5nm, 5.5nm, 6nm, 6.5nm, 7nm, or a range consisting of any two of the above values.

[0071] The polymer included in the intercalation layer 12 provided in the embodiment of the present application can be characterized by mass spectrometry, Fourier transform infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance (H-NMR), and the like. 1 H-NMR) is used for detection and analysis. Compared to other components, the polymer has a very large molecular weight (>10 kg / mol), so ion mass spectrometry (IMS) can be used to detect the presence of the polymer. Fourier transform infrared spectroscopy can detect the characteristic peaks of the polymer, such as the carboxylic acid group, ester group, ether group, etc. of the polymer, which are not present in other layers. A deuterated organic solvent such as DMSO-d6 is used to dissolve the substance on the light absorbing layer 11, and the characteristic peaks of the polymer will appear in the H-NMR spectrum.

[0072] Continuing with Figure 1, the other structures of a solar cell are described using a transverse structure as an example. The solar cell also includes a first electrode layer 14, a second electrode layer 15, and a hole transport layer 16. The hole transport layer 16 is disposed on the side of the light absorbing layer 11 away from the electron transport layer 13. The first electrode layer 14 is disposed on the side of the hole transport layer 16 away from the light absorbing layer 11. The second electrode layer 15 is disposed on the side of the electron transport layer 13 away from the intercalation layer 12.

[0073] The hole transport layer 16 is used to transport the holes generated by the light absorbing layer 11 to the corresponding electrodes and prevent the holes from diffusing in the opposite direction. Hole transport materials include, but are not limited to, at least one of 2,2',7,7'-tetrakis(N,N-p-methoxyanilino)-9,9'-spirobifluorene (Spiro-OMeTAD), methoxytriphenylamine-fluoroformamidine, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], poly(3,4-ethylenedioxythiophene), polystyrenesulfonic acid, poly3-hexylthiophene, triphenylamine with triptycene as the core, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-phenylamino)carbazole-spirobifluorene, polythiophene, phosphate-based monomers, carbazole-based monomers, sulfonic acid-based monomers, triphenylamine-based monomers, aromatic monomers, metal oxides and cuprous thiocyanate, wherein the metal element in the metal oxide selected in the hole transport material includes at least one of Ni, Mo and Cu. Exemplarily, the material of the hole transport layer 16 includes nickel oxide; optionally, the nickel oxide hole transport layer 16 is formed by a magnetron sputtering process.

[0074] The first electrode layer 14 is an anode, and the material of the anode is generally a transparent conductive oxide material, such as FTO (fluorine-doped SnO2 transparent conductive glass), ITO (indium tin oxide transparent conductive glass), AZO (aluminum-doped zinc oxide transparent conductive glass), BZO (boron-doped zinc oxide transparent conductive glass), IZO (indium zinc oxide transparent conductive glass), etc.

[0075] The second electrode layer 15 is a cathode that collects free electrons. The second electrode layer 15 is typically an organic conductive material, an inorganic conductive material, or a mixture of organic and inorganic conductive materials. Examples of organic conductive materials include conductive polymers, including but not limited to at least one of polyethylene dioxythiophene (PEDOT), polythiophene, and polyacetylene. Inorganic conductive materials include but are not limited to at least one of transparent conductive oxides, metals, and carbon derivatives. Specific examples of inorganic conductive materials include Ag, Cu, C, Au, Al, ITO, AZO, BZO, and IZO.

[0076] Continuing with FIG1 , the solar cell further includes a substrate layer 17 . This substrate layer 17 is transparent. The material of substrate layer 17 includes glass and / or a polymer. Optionally, the polymer includes one or more of polyvinyl alcohol (PVA), polyester (PET), polyimide (PI), polyethylene naphthalate (PEN), and polydimethylsiloxane (PDMS). In some embodiments, substrate layer 17 may not be provided.

[0077] In one embodiment, the solar cell further includes a passivation layer 18. The passivation layer 18 is disposed between the light absorbing layer 11 and the hole transport layer 16. The passivation layer 18 fills holes and defects in the light absorbing layer 11 near the surface of the hole transport layer 16, reduces stray reflections, and prevents recombination of photogenerated carriers, thereby improving photoelectric conversion efficiency.

[0078] Optionally, the material of the passivation layer 18 includes but is not limited to Me-4PACz (4-(3,6-dimethyl-9H-carbazol-9-yl)butyl)phosphoric acid.

[0079] The present application also provides an electrical device, which is a common device that includes the solar cell of the present application, such as a device in the fields of communications, transportation, industry and agriculture, and lighting. Examples of the electrical device include satellites, communications equipment, traffic lights, lighthouses, wireless phone booths, monitoring equipment for drilling, power systems, camping lights, electric vehicles, and electronic device chargers.

[0080] Please refer to FIG. 2 , which is a schematic flow chart of a method for preparing a solar cell provided in an embodiment of the present application.

[0081] The method for preparing a solar cell provided in the embodiment of the present application can be used to prepare the solar cell provided in the above embodiment. The method for preparing a solar cell provided in the embodiment of the present application specifically includes:

[0082] Step S01: providing an intercalating layer slurry, wherein the intercalating layer slurry comprises a polymer, and the molecular weight of the polymer is greater than 10 kg / mol.

[0083] In one embodiment, the polymer includes one or more of polymethyl methacrylate, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polyethylene vinyl acetate, polyacrylonitrile, linear polyethyleneimine, and branched polyethyleneimine.

[0084] In one embodiment, the intercalation layer slurry includes a polymer, and the concentration range of the polymer in the intercalation layer slurry is 0.5 mg / mL-2.0 mg / mL, so as to be able to form a thinner and dense film layer. The formed film layer can play a better barrier and passivation role, and has a smaller resistance and less impact on the current. The concentration of the intercalation layer slurry is positively correlated with the thickness of the intercalation layer formed therefrom. Exemplarily, the concentration range of the polymer in the intercalation layer slurry is 0.5 mg / mL, 1.0 mg / mL, 1.5 mg / mL, 2.0 mg / mL, or a range consisting of any two of the above values, for example, 1.0 mg / mL-1.5 mg / mL, 1.0 mg / mL-2.0 mg / mL, etc.

[0085] Specifically, the polymer plays a role in protecting the light absorbing layer 11, preventing the light absorbing layer 11 from being destroyed by the external environment (for example, water and oxygen) in step S02; the polymer can block the reaction between the electron transport layer 13 and the light absorbing layer 11, maintaining the stability of the light absorbing layer 11; the polymer can also passivate defects on the surface of the light absorbing layer 11, fill the holes and defects on the surface of the light absorbing layer 11, reduce stray reflections, block the recombination of photogenerated carriers, and improve the photoelectric conversion efficiency.

[0086] In one embodiment, the intercalation layer slurry includes a polymer and fullerenes and their derivatives, the concentration range of fullerenes and their derivatives in the intercalation layer slurry is 10 mg / mL-20 mg / mL, and the mass ratio of polymer to fullerenes and their derivatives is 1%-10%, so as to form a thin and dense film layer. The formed film layer can play a good barrier and passivation role, and has low resistance and little effect on current. The concentration of the intercalation layer slurry is positively correlated with the thickness of the intercalation layer formed by it. Exemplarily, the concentration range of the polymer in the intercalation layer slurry is 10 mg / mL, 11 mg / mL, 12 mg / mL, 13 mg / mL, 14 mg / mL, 15 mg / mL, 16 mg / mL, 17 mg / mL, 18 mg / mL, 19 mg / mL, 20 mg / mL, or a range consisting of any two of the above values, for example, 12 mg / mL-18 mg / mL, 10 mg / mL-14 mg / mL, etc. For example, the mass ratio of the polymer to the fullerene and its derivatives in the intercalated layer 12 can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., or a range consisting of any two of the above values, for example, 3%-4%, 6%-7%, 7%-10%, etc.

[0087] Specifically, fullerene and its derivatives have the function of regulating energy levels, so that the energy levels between the light absorption layer 11 and the electron transport layer 13 in step S02 are more matched, forming an efficient electron transport channel, preventing the electrons and holes generated by the light absorption layer 11 from recombination, improving the efficiency of the device, and at the same time improving the photoelectric conversion efficiency.

[0088] Optionally, fullerene and its derivatives include [6,6]-phenyl-C61-butadienedicarboxylic acid dibutyl ester (PC 61 BM). PC 61 BM has excellent electron transport properties and high charge mobility; PC 61 BM can be used to promote the transport and collection of electrons, thus, through PC 61 BM can form an efficient electron transmission channel, which can effectively prevent the recombination of photogenerated electrons and holes, improve the efficiency of semiconductor devices, and improve the photoelectric conversion efficiency. 61 The BM makes the energy levels between the light absorbing layer 11 and the electron transport layer 13 in step S02 more matched, forms an efficient electron transport channel, prevents electrons and holes from recombining, and improves the photoelectric conversion efficiency.

[0089] In one embodiment, the solvent of the intercalating layer slurry includes one or more of chlorobenzene (CB), dichloromethane (DCM), and chloroform. It should be noted that the above solvents are applicable regardless of whether the intercalating layer slurry includes a polymer or a polymer and fullerenes and their derivatives.

[0090] Optionally, the intercalating layer slurry includes a polymer, and the solvent of the intercalating layer slurry includes chlorobenzene, which can dissolve the polymer well. Selecting a single chlorobenzene as the solvent simplifies the preparation process of the intercalating layer slurry.

[0091] Optionally, the intercalation layer slurry includes a polymer and fullerene and its derivatives, and the solvent of the intercalation layer slurry includes dichloromethane and chlorobenzene. Dichloromethane and chlorobenzene are well soluble in each other and can dissolve polymers and fullerene and its derivatives (e.g., PC 61 BM), which can realize the preparation of fullerene and its derivative layers and polymer passivation in one step, simplify the process and reduce costs.

[0092] Optionally, the solvent for the intercalating layer slurry is dichloromethane:chlorobenzene in a volume ratio of (0-2):1. The polymer or a mixture of the polymer and fullerene and its derivatives has good solubility in the solvent at the above ratio, making the intercalating layer slurry more uniform. Exemplarily, the volume ratio of the solvent for the intercalating layer slurry can be 0, 0.5:1, 1:1, 1.5:1, 2:1, etc., or a range consisting of any two of the above values, for example, 0.5:1-2:1, 1:1-2:1, 0-1:1, etc.

[0093] Optionally, the solvent of the intercalating layer slurry is dichloromethane:chlorobenzene:chloroform in a volume ratio of (0-2):1:(0-2).

[0094] When the intercalating layer slurry includes a polymer and fullerenes and their derivatives, selecting one or more of chlorobenzene (CB), dichloromethane (DCM), and chloroform as the solvent for the intercalating layer slurry allows for the preparation of the fullerene and their derivatives layer and polymer passivation in a single step. In other embodiments, the polymer layer and the fullerene and their derivatives layer can be formed in two separate steps. If the polymer layer is formed first, followed by the fullerene and their derivatives layer, the solvent used to form the fullerene and their derivatives layer must be insoluble in the polymer. If the fullerene and their derivatives layer is formed first, followed by the polymer layer, the solvent used to form the polymer layer must be insoluble in the fullerene and their derivatives.

[0095] In one embodiment, the intercalation layer slurry further includes an alcohol additive to improve wettability and device performance. Optionally, the alcohol additive may be at least one of ethanol and isopropanol. Optionally, the volume ratio of the alcohol additive to the solvent is (0.05:1) to (0.25:1).

[0096] Step S02 : forming an intercalation layer 12 on a side of the light absorbing layer 11 close to the electron transport layer 13 .

[0097] In one embodiment, a dynamic drop-addition process is used to form the intercalation layer 12 on the side of the light absorbing layer 11 near the electron transport layer 13. It should be noted that after the dynamic drop-addition process, a baking, annealing, or other process can be optionally used to form the intercalation layer 12, and the design is based on specific needs. For example, after the dynamic drop-addition process, the layer is dried at 100°C for 10 minutes.

[0098] Optionally, the rotation speed of the dynamic dropping process is 3000-7000 rpm, and the intercalated layer 12 formed is a relatively thin and dense film layer. Exemplarily, the rotation speed of the dynamic dropping process is 3000 rpm, 4000 rpm, 5000 rpm, 6000 rpm, 7000 rpm, or a range consisting of any two of the above values, for example, 4000-6000 rpm. Exemplarily, 50 μL-150 μL of the slurry is dynamically dropped onto the light absorbing layer 11 at 5000 rpm to form the intercalated layer 12.

[0099] Optionally, when the intercalation layer slurry includes a polymer, a dynamic dropping process is used to form the intercalation layer 12 on a side of the light absorbing layer 11 close to the electron transport layer 13 .

[0100] In one embodiment, a spin coating process is used to form the intercalation layer 12 on the side of the light absorbing layer 11 near the electron transport layer 13. It should be noted that after the spin coating process, a baking process, annealing process, or other processes can be optionally used to form the intercalation layer 12, and the design is based on specific needs. For example, after the spin coating process, the intercalation layer 12 is dried at 100°C for 10 minutes.

[0101] Optionally, the rotation speed of the spin coating process is 3000rpm-7000rpm, and the acceleration is 1000rpm / s-3000rpm / s, and the intercalated layer formed is a thin and dense film layer. Exemplarily, the rotation speed of the spin coating process is 3000rpm, 4000rpm, 5000rpm, 6000rpm, 7000rpm, or a range consisting of any two of the above values, for example, 4000rpm-6000rpm, etc. Exemplarily, the acceleration of the spin coating process is 1000rpm / s, 1500rpm / s, 2000rpm / s, 2500rpm / s, 3000rpm / s, or a range consisting of any two of the above values, for example, 1500rpm-2500rpm, 1500rpm-3000rpm, etc. For example, 90 μL of the slurry is statically spin-coated on the light absorbing layer 11 at a rotation speed of 5000 rpm and an acceleration of 2000 rpm / s for 30 seconds to form the intercalating layer 12 .

[0102] Optionally, when the intercalation layer slurry includes a polymer and fullerene and its derivatives, a spin coating process is used to form the intercalation layer 12 on a side of the light absorbing layer 11 close to the electron transport layer 13 .

[0103] In one embodiment, the intercalation layer slurry includes a polymer, the solvent of the intercalation layer slurry includes chlorobenzene, and the concentration of the polymer in the intercalation layer slurry ranges from 0.5 mg / mL to 2.0 mg / mL. A dynamic droplet addition process is used to form the intercalation layer on the side of the light absorbing layer 11 near the electron transport layer 13; specifically, the rotation speed of the dynamic droplet addition process is 3000 rpm to 7000 rpm.

[0104] In one embodiment, the intercalation layer slurry includes a polymer and fullerene and its derivatives, the solvent of the intercalation layer slurry is dichloromethane:chlorobenzene in a volume ratio of (0-2):1, the concentration of fullerene and its derivatives in the intercalation layer slurry ranges from 10 mg / mL to 20 mg / mL, and the mass ratio of polymer to fullerene and its derivatives is from 1% to 10%. Optionally, the fullerene and its derivatives include [6,6]-phenyl-C61-butadienedicarboxylic acid dibutyl ester (PC 61BM). The intercalation layer 12 is formed on the side of the light absorbing layer 11 close to the electron transport layer 13 by a spin coating process; specifically, the rotation speed of the spin coating process is 3000 rpm-7000 rpm, and the acceleration is 1000 rpm / s-3000 rpm / s.

[0105] The method for preparing the solar cell provided in the embodiment of the present application also includes forming a first electrode layer 14, a second electrode layer 15 and a hole transport layer 16. The specific preparation method of the first electrode layer 14, the second electrode layer 15 and the hole transport layer 16 can be referred to the existing technology and will not be repeated here.

[0106] The solar cell preparation method provided in the embodiment of the present application forms an intercalation layer 12 between the light absorption layer 11 and the electron transport layer 13. The intercalation layer 12 protects the light absorption layer 11 and prevents the light absorption layer 11 from being destroyed by the external environment (for example, water and oxygen). The intercalation layer 12 can block the reaction between the electron transport layer 13 and the light absorption layer 11, thereby maintaining the stability of the light absorption layer 11. The intercalation layer 12 can also passivate defects on the surface of the light absorption layer 11. The intercalation layer 12 fills the holes and defects on the surface of the light absorption layer 11, reduces stray reflections, prevents the recombination of photogenerated carriers, and improves the photoelectric conversion efficiency.

[0107] The beneficial effects of the present application are further illustrated below with reference to the examples.

[0108] In order to make the technical problems, technical solutions and beneficial effects solved by the embodiments of the present application clearer, the following will be further described in detail with reference to the embodiments and drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its applications. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0109] Example 1:

[0110] (1) ITO conductive glass cleaning

[0111] The etched ITO glass was ultrasonically cleaned in a surfactant aqueous solution, distilled water, acetone, and alcohol for 30 minutes respectively, and finally dried with nitrogen for later use.

[0112] (2)NiO x Preparation of hole transport layer

[0113] In this example, NiOx was used as the transport layer material. Before the experiment began, a 20 mg / mL aqueous dispersion of nickel oxide nanoparticles was prepared. The cleaned ITO glass was then plasma treated for 3 minutes to enhance the subsequent NiO x The ITO glass surface was then spin-coated with an aqueous dispersion of nickel oxide nanoparticles at 4000 rpm for 30 seconds. The surface was then transferred to a 100°C hot plate for annealing for 10 minutes and then cooled to room temperature for later use.

[0114] (3) Preparation of passivation layer

[0115] In this embodiment, Me-4PACz is used as the passivation layer.

[0116] (4) Preparation of CH3NH3PbI3 perovskite layer

[0117] This embodiment adopts a one-step method to prepare the perovskite layer.

[0118] Preparation of perovskite precursor solution: MAI powder, PbI2 powder and lead acetate powder were mixed in a ratio of 2.2 mmol: 0.4 mmol: 0.6 mmol, and the mixture was added to 1 mL of DMF and magnetically stirred for 6 hours.

[0119] Then, in a glove box, 35 μL of CH 3 NH 3 PbI 3 perovskite precursor solution was added to the upper surface of the passivation layer and spin coating was started at 4000 rpm for 30 seconds. After spin coating, it was transferred to a hot stage at 100°C for annealing and crystallization for 10 minutes to obtain a uniform and dense perovskite film.

[0120] (5) Preparation of intercalating layer

[0121] An intercalation layer slurry with a concentration of 1.0 mg / mL was prepared using polymethyl methacrylate and chlorobenzene, and 100 μL of the intercalation layer slurry was dynamically dripped onto the perovskite layer at 5000 rpm.

[0122] (6) Preparation of oxide electron transport layer and Ag electrode

[0123] Tin oxide is deposited onto the surface of the intercalated layer using an atomic layer deposition process. The tin source is tetra(diethylamine)tin, and the reaction source is water. After the tin source is combined, excess compounds are blown off, the reaction source is purged, and excess compounds are blown off again, completing a cycle. This cycle is repeated 200 times to produce a 20nm thick layer of tin oxide.

[0124] Transfer the device after atomic layer deposition to the evaporation chamber, put the silver particles into the evaporation boat, and close the chamber door. -4 Pa, with The 100nm silver electrode was evaporated at a speed of 100nm, and taken out after the vacuum was stopped, finally completing the preparation of the perovskite solar cell.

[0125] The preparation process of other embodiments and comparative examples is similar to that of the above embodiment 1, except that the solute (polymer or a mixture of polymer and fullerene and its derivatives) and the concentration of the solute of the intercalation layer slurry are different, as shown in Table 1.

[0126] It should be noted that the solvent of the intercalation layer slurry in each embodiment is chlorobenzene. The thickness of the intercalation layer 12 formed by the intercalation layer slurry in each embodiment is 5nm. 61 The concentration of BM was 20 mg / ml. In Table 1, the molecular weight of PMMA was 15,000 g / mol, the molecular weight of PEO was 100,000 g / mol, the molecular weight of PVP was 40,000 g / mol, the molecular weight of PAA was 450,000 g / mol, the molecular weight of PAN was 150,000 g / mol, the molecular weight of L-PEI was 15,000 g / mol, the molecular weight of B-PEI was 25,000 g / mol, and the molecular weight of PEVA was 50,000 g / mol.

[0127] The relevant parameter testing process of the examples and comparative examples of the present application is as follows:

[0128] IV measurement method:

[0129] By changing the bias voltage point and measuring the current at the same time, the IV characteristics (current-voltage curve) of the measured sample can be obtained.

[0130] a) Place the test fixture containing the sample cell on the sample holder so that it is located in the measurement plane and ensure that the sample cell is located at the center of the solar simulator's output light spot (or the normal line of the photovoltaic cell is parallel to the center line of the solar simulator's light beam);

[0131] b) At 1000W / m 2 Under the condition of irradiance, a mask is installed on the sample battery to be tested, and the temperature of the sample battery is controlled by a temperature monitoring device so that the temperature of the sample is maintained at (25±3℃) during the measurement process;

[0132] c) Set the scanning direction, voltage range, scanning interval voltage and scanning interval time. It is recommended that the scanning interval should not be greater than 0.02V and the interval between two adjacent points should not be less than 0.3s. Measure the forward and reverse current-voltage characteristics of the sample battery under test and record the open circuit voltage V OC , short-circuit current J SC .

[0133] Calculation formula: Fill factor FF = Jmax *V max / (V OC *J SC ), energy conversion efficiency PCE=P max / P in .P in is the incident light intensity, which is equal to 10 3 W / m 2 .

[0134] Table 1 Test parameters of various embodiments and comparative examples

[0135] In Table 1, the device's photoelectric conversion efficiency is 0, indicating device failure. Table 1 shows that the placement of intercalation layer 12 between light-absorbing layer 11 and electron-transporting layer 13 improves photoelectric conversion efficiency. Compared to the photoelectric conversion efficiency when intercalation layer 12 comprises a polymer, the photoelectric conversion efficiency is higher when intercalation layer 12 comprises a polymer and fullerenes and their derivatives.

[0136] The above description is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A solar cell, wherein: include: A light absorbing layer, an intercalating layer and an electron transporting layer, wherein the intercalating layer is located between the light absorbing layer and the electron transporting layer; The interpenetrating layer comprises a polymer having a molecular weight greater than 10 kg / mol.

2. The solar cell according to claim 1, wherein: The polymer includes one or more of polymethyl methacrylate, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polyethylene vinyl acetate, polyacrylonitrile, linear polyethylene imine, and branched polyethylene imine.

3. The solar cell according to claim 1, wherein: The intercalated layer also includes fullerene and its derivatives.

4. The solar cell according to claim 3, wherein: The fullerene and its derivatives include one or more of fullerene C60 (C60), fullerene C70 (C70), [6,6]-phenyl-C61-butyric acid methyl ester, [6,6]-phenyl-C71-butyric acid methyl ester, and indene-C60 bis-adduct.

5. The solar cell according to claim 3 or 4, wherein: The fullerene and its derivatives include [6,6]-phenyl-C61-butadienedicarboxylic acid dibutyl ester.

6. The solar cell according to any one of claims 3 to 5, wherein: The mass ratio of the polymer to the fullerene and its derivatives in the intercalated layer is 1%-10%.

7. The solar cell according to any one of claims 1 to 6, wherein: The thickness of the intercalated layer is 2nm-10nm.

8. The solar cell according to any one of claims 1 to 7, wherein: The thickness of the intercalated layer is 3nm-7nm.

9. The solar cell according to any one of claims 1 to 8, wherein: The electron transport layer includes an atomic layer deposited oxide.

10. The solar cell according to claim 9, wherein: The oxide includes one or more of tin oxide, aluminum oxide, and zinc oxide.

11. The solar cell according to any one of claims 1 to 10, wherein: The light absorbing layer comprises a perovskite material; optionally, the perovskite material comprises a halide perovskite.

12. The solar cell according to any one of claims 1 to 11, wherein: The solar cell has a transverse structure.

13. The solar cell according to any one of claims 1 to 12, wherein: The solar cell also includes a first electrode layer, a second electrode layer and a hole transport layer, the hole transport layer is arranged on a side of the light absorption layer away from the electron transport layer, the first electrode layer is arranged on a side of the hole transport layer away from the light absorption layer, and the second electrode layer is arranged on a side of the electron transport layer away from the intercalation layer.

14. The solar cell according to any one of claims 1 to 13, wherein: The solar cell further includes a passivation layer disposed between the light absorbing layer and the hole transporting layer.

15. A method for preparing a solar cell, wherein: include: Providing an interleaved layer slurry, the interleaved layer slurry comprising a polymer, the molecular weight of the polymer being greater than 10 kg / mol; An intercalation layer is formed on a side of the light absorbing layer close to the electron transporting layer.

16. The method for preparing a solar cell according to claim 15, wherein: The polymer includes one or more of polymethyl methacrylate, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polyethylene vinyl acetate, polyacrylonitrile, linear polyethylene imine, and branched polyethylene imine.

17. The method for preparing a solar cell according to claim 15 or 16, wherein: The concentration of the polymer in the interpenetrating layer slurry is in the range of 0.5 mg / mL to 2.0 mg / mL.

18. The method for preparing a solar cell according to any one of claims 15 to 17, wherein: The intercalation layer slurry comprises the polymer and fullerene and its derivatives; the concentration range of the fullerene and its derivatives is 10 mg / mL-20 mg / mL.

19. The method for preparing a solar cell according to claim 18, wherein: The mass ratio of the polymer to the fullerene and its derivatives is 1%-10%.

20. The method for preparing a solar cell according to any one of claims 15 to 19, wherein: The solvent of the intercalating layer slurry includes one or more of chlorobenzene, dichloromethane and chloroform.

21. The method for preparing a solar cell according to claim 20, wherein: The solvent of the intercalation layer slurry is dichloromethane:chlorobenzene in a volume ratio of (0-2):

1.

22. An electrical device, wherein: A solar cell comprising the solar cell according to any one of claims 1 to 14, or a solar cell prepared by the method for preparing a solar cell according to any one of claims 15 to 21.

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