Perovskite solar cell, preparation method thereof, photovoltaic module and photovoltaic system

Abstract

The embodiment of the invention provides a perovskite solar cell, a preparation method thereof, a photovoltaic module and a photovoltaic system, and relates to the technical field of perovskite solar cells. The perovskite solar cell comprises a self-assembly single layer, an interface modification layer and a perovskite light absorption layer which are stacked in sequence, the material of the interface modification layer comprises acetophenone oxime. The acetophenone oxime interface modification layer is introduced between the self-assembly monolayer and the perovskite light absorption layer, and groups such as carboxyl in acetophenone oxime interact with each other, so that the problem of poor wettability of the self-assembly monolayer caused by an SAM molecular material can be improved, the phenomenon of uneven coverage of a perovskite film can be effectively relieved, and the perovskite light absorption performance is improved. According to the perovskite solar cell provided by the invention, a compact perovskite light absorption layer with high crystal quality can be conveniently formed, and unsaturated N atoms in the oximido group can passivate defects at the interface of the perovskite light absorption layer and the self-assembly single layer and can be coordinated with free Pb < + >, so that the short-circuit current density, the open-circuit voltage and the photoelectric conversion efficiency of the perovskite solar cell are improved.

Description

Technical Field

[0001] The present application relates to the technical field of perovskite solar cells, and in particular to a perovskite solar cell and a preparation method thereof, a photovoltaic module and a photovoltaic system. Background Art

[0002] Perovskite materials originally referred to a mineral composed of the inorganic calcium titanate (CaTiO3), and later used to refer to a family of compounds with an ABX3 structure. Perovskite materials can be used to prepare perovskite solar cells (PSCs). Perovskite solar cells have broad application prospects due to their low-temperature solution processability and excellent optoelectronic properties. In addition to engineering the composition and crystallization kinetics of perovskites, interface engineering has been used as an effective tool to improve the efficiency and stability of perovskite solar cells. In perovskite solar cells, the hole selection layer (HSL) is crucial to the device performance. Recently, self-assembled monolayers (SAMs) have been used as effective hole selection layers (HSLs) to replace traditional organic hole transport layers (HTLs).

[0003] Self-assembled monolayers (SAMs) have the advantages of easily adjustable perovskite energy level arrangement, less parasitic absorption, sufficient stability and easy processing, which are compatible with low-cost and scalable production. The SAM molecules in self-assembled monolayers (SAMs) usually include an anchor group that can bind to the substrate, a flexible spacer group that provides sufficient rotational freedom for self-assembly, and a functional head group to promote effective hole extraction. Through reasonable molecular design, ultrathin and efficient hole selection layers (HSLs) can be formed. Self-assembled monolayers (SAMs) as hole selection layers (HSLs) can significantly reduce charge transport losses, thereby improving the short-circuit current density (JSC) and open-circuit voltage (VOC) in perovskite solar cells and achieving high power conversion efficiency. However, these self-assembled monolayers (SAMs) have poor wettability of SAM molecular materials, resulting in uneven coverage of perovskite films.

[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] The embodiments of the present application provide a perovskite solar cell and a preparation method thereof, a photovoltaic module and a photovoltaic system to solve or alleviate the technical problems raised above. The embodiments of the present application introduce an acetophenone oxime interface modification layer between the self-assembled monolayer and the perovskite light absorption layer. The carboxyl groups and other groups in the acetophenone oxime interact with each other, which can well improve the problem of poor wettability of the self-assembled monolayer caused by SAM molecular materials, effectively alleviate the phenomenon of uneven coverage of the perovskite film, and facilitate the formation of a dense and high-crystalline perovskite light absorption layer. At the same time, the unsaturated N atoms in the oxime group can also passivate the defects at the interface between the perovskite light absorption layer and the self-assembled monolayer, and can also react with free Pb + Coordination is carried out to improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of perovskite solar cells.

[0006] To achieve the above purpose, this application adopts the following technical solutions: A perovskite solar cell comprises: a self-assembled monolayer, an interface modification layer and a perovskite light absorption layer stacked in sequence; the material of the interface modification layer comprises acetophenone oxime.

[0007] In some embodiments, the thickness of the interface modification layer is 0.5-15 nm.

[0008] In some embodiments, the thickness of the interface modification layer is 1-10 nm.

[0009] In some embodiments, the interface modification layer is formed based on an acetophenone oxime solution; the acetophenone oxime solution includes acetophenone oxime and an organic solvent; wherein the organic solvent includes one or more of ethanol and isopropanol.

[0010] In some embodiments, the concentration of the acetophenone oxime in the acetophenone oxime solution is 0.2-1.5 mg / ml.

[0011] In some embodiments, the concentration of the acetophenone oxime in the acetophenone oxime solution is 0.4-1.2 mg / ml.

[0012] In some embodiments, the material of the self-assembled monolayer includes: one or more of a single-molecule self-assembled material containing a phosphate group and a single-molecule self-assembled material containing a carboxylic acid group.

[0013] In some embodiments, the self-assembled monolayer is formed based on a SAM solution; the SAM solution includes SAM and a polar solvent; wherein the polar solvent includes one or more of ethanol and isopropanol, and the SAM includes: one or more of a single-molecule self-assembled material containing a phosphate group and a single-molecule self-assembled material containing a carboxylic acid group.

[0014] In some embodiments, the concentration of SAM in the SAM solution is 0.2-1.0 mg / ml.

[0015] In some embodiments, the perovskite light absorbing layer is formed by a perovskite precursor solution; the perovskite precursor solution comprises: a perovskite material and a solvent; Wherein, the perovskite material includes any one of FAMAPbI, FACsPbI3, and FAMACsPbI3; The solvent includes any one of a mixed solution of N,N-dimethylformamide and dimethyl sulfoxide and a mixed solution of γ-butyrolactone and N-methylpyrrolidone; the volume ratio of N,N-dimethylformamide to dimethyl sulfoxide in the mixed solution of N,N-dimethylformamide and dimethyl sulfoxide is 3-5:1; the volume ratio of γ-butyrolactone to N-methylpyrrolidone in the mixed solution of γ-butyrolactone and N-methylpyrrolidone is 3-5:1.

[0016] In some embodiments, a conductive substrate, an electron transport layer, a hole blocking layer, and a metal electrode are also included; Wherein, the self-assembled monolayer, the interface modification layer, the perovskite light absorption layer, the electron transport layer, the hole blocking layer, and the metal electrode are sequentially stacked on the conductive substrate.

[0017] The embodiment of the present application also provides a method for preparing a perovskite solar cell, comprising: sequentially preparing a self-assembled monolayer, an interface modification layer, and a perovskite light absorption layer on a conductive substrate; Wherein, the material of the interface modification layer includes acetophenone oxime.

[0018] In some embodiments, after preparing the self-assembled monolayer and before preparing the interface modification layer, the method further comprises performing a first annealing; the annealing temperature of the first annealing is 100-120° C., and the annealing time is 10-15 min; And / or, after preparing the interface modification layer and before preparing the perovskite light absorption layer, the method further comprises performing a second annealing; the annealing temperature of the second annealing is 100-120° C., and the annealing time is 10-15 min; And / or, after preparing the perovskite light absorbing layer and before preparing other functional layers on the perovskite light absorbing layer, it also includes performing a third annealing; the annealing temperature of the third annealing is 100-150° C., and the annealing time is 15-35 min.

[0019] The present application also provides a photovoltaic cell assembly, including the above-mentioned perovskite solar cell; and / or The perovskite solar cell prepared by the above method.

[0020] An embodiment of the present application also provides a photovoltaic system, including the above-mentioned photovoltaic cell assembly.

[0021] The above technical solution adopted in the embodiment of the present application may have the following advantages: The acetophenone oxime interface modification layer is introduced between the self-assembled monolayer and the perovskite light absorption layer. The carboxyl groups in the acetophenone oxime interact with each other, which can effectively improve the poor wettability of the self-assembled monolayer caused by the SAM molecular material, and can effectively alleviate the uneven coverage of the perovskite film, so as to form a dense and high-quality perovskite light absorption layer. At the same time, the unsaturated N atoms in the oxime group can also passivate the defects at the interface between the perovskite light absorption layer and the self-assembled monolayer, and can also react with free Pb + Coordination is carried out to improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of perovskite solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0023] Figure 1 is a schematic diagram of the structure of a perovskite solar cell provided in an embodiment of the present application; Figure 2 is a SEM image of the perovskite light absorption layer provided in Example 1 of the present application; Figure 3 is a SEM image of the perovskite light absorption layer provided in Comparative Example 1 of the present application; Description of reference numerals: 1. Conductive substrate; 2. Self-assembled monolayer; 3. Interface modification layer; 4. Perovskite light absorption layer; 5. Electron transport layer; 6. Hole blocking layer; 7. Metal electrode. DETAILED DESCRIPTION

[0024] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings. In the accompanying drawings, for clarity, the sizes of layers, regions, elements and their relative sizes may be exaggerated. Wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limitations on the present application. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0025] 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 can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present disclosure, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not mean that the present disclosure necessarily has the first element, component, region, layer or part.

[0026] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to an integer in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each 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 range disclosed in the present application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows for broadly including quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.

[0029] The present application aims to provide a perovskite solar cell and a preparation method thereof, a photovoltaic module and a photovoltaic system. An acetophenone oxime interface modification layer is introduced between the self-assembled monolayer and the perovskite light absorption layer. The carboxyl groups and other groups in the acetophenone oxime interact with each other, which can well improve the problem of poor wettability of the self-assembled monolayer caused by SAM molecular materials, effectively alleviate the phenomenon of uneven coverage of the perovskite film, and facilitate the formation of a dense and high-crystalline perovskite light absorption layer. At the same time, the unsaturated N atoms in the oxime group can also passivate the defects at the interface between the perovskite light absorption layer and the self-assembled monolayer, and can also react with free Pb + Coordination is carried out to improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of perovskite solar cells.

[0030] Below, exemplary embodiments of the present application will be described in more detail with reference to the accompanying drawings. It should be noted that these exemplary embodiments can be implemented in many different forms and should not be construed as being limited to the embodiments described herein.

[0031] An embodiment of the present application provides a perovskite solar cell, comprising: a self-assembled monolayer, an interface modification layer and a perovskite light absorption layer stacked in sequence; the material of the interface modification layer comprises acetophenone oxime.

[0032] In the embodiment of the present application, the thickness of the self-assembled monolayer can be 10-100 nm (for example, 20 nm, 30 nm, 40 nm, 60 nm, 80 nm, 100 nm). The preparation method of the self-assembled monolayer can include one or more of slit coating, spin coating, and blade coating. In the embodiment of the present application, other functional layers can also be included, and the required functional layers can be introduced according to actual needs to achieve specific functions.

[0033] In the embodiment of the present application, the thickness of the interface modification layer may be 1-20 nm (eg, 1 nm, 5 nm, 10 nm, 15 nm, 20 nm). The preparation method of the interface modification layer may include one or more of slit coating, spin coating, and blade coating.

[0034] In the embodiment of the present application, the perovskite light absorption layer is made of a perovskite material. The thickness of the perovskite light absorption layer can be 300-800nm. The perovskite material is an ABX3 structure; A is a monovalent cation; B is a divalent cation; X is a monovalent anion. More specifically, A includes but is not limited to a mixture of one or more monovalent cations of cesium (Cs), rubidium (Rb), methylamine (CH3NH3), and guanidine (CH2(NH2)2); B includes but is not limited to a mixture of one or more divalent cations of lead (Pb), copper (Cu), zinc (Zn), gallium (Ga), tin (Sn), and calcium (Ca); X includes but is not limited to a mixture of one or more monovalent anions of iodine (I), bromine (Br), chlorine (Cl), fluorine (F), and thiocyanate ion (SCN).

[0035] In the embodiment of the present application, the preparation method of the perovskite light absorbing layer is one or more of spin coating, scraper coating, evaporation, printing, spraying, spray pyrolysis, and slit coating; that is, the perovskite light absorbing layer is formed on the upper surface of the self-assembled monolayer by spin coating, scraper coating, etc.; different preparation methods will also have some influence on the crystallization of the perovskite light absorbing layer, and the corresponding preparation method can be selected according to actual needs. When the perovskite light absorbing layer is obtained by coating the upper surface of the self-assembled monolayer by one-step spin coating or slit coating, the coating speed can be 4000-5000 rpm / min (for example, 4000 rpm / min, 4500 rpm / min, 5000 rpm / min), and the coating time can be 30-40s (for example, 30s, 35s, 40s).

[0036] In the embodiment of the present application, an acetophenone oxime interface modification layer is introduced between the self-assembled monolayer and the perovskite light absorbing layer. The carboxyl groups and other groups in the acetophenone oxime interact with each other, which can well improve the problem of poor wettability of the self-assembled monolayer caused by the SAM molecular material, and can effectively alleviate the phenomenon of uneven coverage of the perovskite film, so as to facilitate the formation of a dense and high-crystalline perovskite light absorbing layer. At the same time, the unsaturated N atoms in the oxime group can also passivate the defects at the interface between the perovskite light absorbing layer and the self-assembled monolayer, and can also react with free Pb + Coordination is carried out to improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of perovskite solar cells.

[0037] In an optional embodiment, the thickness of the interface modification layer is 0.5-15 nm (for example, 0.5 nm, 1 nm, 3 nm, 5 nm, 8 nm, 10 nm, 12 nm, 13 nm, 15 nm). Controlling the thickness of the interface modification layer can optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, improve the extraction and transmission efficiency of holes, and thus improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0038] In an optional embodiment, the thickness of the interface modification layer is 1-10 nm (eg, 1 nm, 3 nm, 5 nm, 8 nm, 10 nm).

[0039] In the embodiments of the present application, the thickness of the interface modification layer is optimized to optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, thereby improving the extraction and transmission efficiency of holes, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0040] In an optional embodiment, the interface modification layer is formed based on an acetophenone oxime solution; the acetophenone oxime solution includes acetophenone oxime and an organic solvent; wherein the organic solvent includes one or more of ethanol and isopropanol.

[0041] In the embodiments of the present application, the materials and solvents of the interface modification layer are optimized to optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, promote the effective injection and transmission of holes, and thus improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0042] In an optional embodiment, the concentration of the acetophenone oxime in the acetophenone oxime solution is 0.2-1.5 mg / ml (e.g., 0.2 mg / ml, 0.4 mg / ml, 0.6 mg / ml, 0.8 mg / ml, 1.0 mg / ml, 1.2 mg / ml, 1.5 mg / ml). Controlling the concentration of acetophenone oxime can optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, promote the effective injection and transmission of holes, and thus improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0043] In an optional embodiment, the concentration of the acetophenone oxime in the acetophenone oxime solution is 0.4-1.2 mg / ml (for example, 0.4 mg / ml, 0.6 mg / ml, 0.8 mg / ml, 1.0 mg / ml, 1.2 mg / ml).

[0044] In the embodiments of the present application, optimizing the concentration of acetophenone oxime can optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, promote the effective injection and transmission of holes, and thus improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0045] In an optional embodiment, the material of the self-assembled monolayer includes: one or more of a single-molecule self-assembled material containing a phosphate group and a single-molecule self-assembled material containing a carboxylic acid group.

[0046] In the embodiments of the present application, various performances of the perovskite solar cell are improved by introducing an acetophenone oxime interface modification layer between the self-assembled monolayer and the perovskite light absorption layer. The method has the advantages of simple preparation process, low material cost, obvious passivation effect, and obvious effect of improving the wettability of the self-assembled monolayer. The method is applicable to both single-molecule self-assembled materials containing phosphate groups and single-molecule self-assembled materials containing carboxylic acid groups, and is conducive to commercial production.

[0047] In an optional embodiment, the self-assembled monolayer is formed based on a SAM solution; the SAM solution includes SAM and a polar solvent; wherein the polar solvent includes one or more of ethanol and isopropanol, and the SAM includes: one or more of a single-molecule self-assembled material containing a phosphate group and a single-molecule self-assembled material containing a carboxylic acid group.

[0048] In the embodiment of the present application, SAM includes one or more of: MeO-2PACZ ([2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid), 2PACZ ([2-(9H-carbazole-9-yl)ethyl]phosphonic acid), Me-4PACZ ([4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid), porphyrin-SAMs (porphyrin-SAMs is a derivative of porphyrin, comprising a porphyrin macrocyclic structure and a carboxylic acid group). In the embodiment of the present application, the amount of SAM added to the SAM solution can be limited according to actual needs.

[0049] In the embodiments of the present application, the materials and solvents of the self-assembled monolayer are optimized, the contact between the self-assembled monolayer and the acetophenone oxime interface modification layer can be optimized, the wettability of the self-assembled monolayer can be effectively improved, and a dense and high-crystalline perovskite light absorption layer can be formed, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0050] In an optional embodiment, the concentration of SAM in the SAM solution is 0.2-1.0 mg / ml (e.g., 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, 1.0 mg / ml).

[0051] In the embodiments of the present application, optimizing the concentration of SAM can effectively improve the wettability of the self-assembled monolayer, facilitate the formation of a dense and high-crystalline perovskite light absorption layer, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0052] In an optional embodiment, the perovskite light absorbing layer is formed by a perovskite precursor solution; the perovskite precursor solution comprises: a perovskite material and a solvent; Wherein, the perovskite material includes any one of FAMAPbI, FACsPbI3, and FAMACsPbI3; The solvent includes any one of a mixed solution of N,N-dimethylformamide and dimethyl sulfoxide and a mixed solution of γ-butyrolactone and N-methylpyrrolidone; the volume ratio of N,N-dimethylformamide to dimethyl sulfoxide in the mixed solution of N,N-dimethylformamide and dimethyl sulfoxide is 3-5:1 (for example, 3:1, 4:1, 5:1); the volume ratio of γ-butyrolactone to N-methylpyrrolidone in the mixed solution of γ-butyrolactone and N-methylpyrrolidone is (for example, 3:1, 4:1, 5:1).

[0053] In the embodiments of the present application, by optimizing the type of perovskite material, adjusting the selection and ratio of the solvent, and optimizing the crystallization quality and morphology of the perovskite light absorption layer, the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell can be further improved.

[0054] In an optional embodiment, it further includes a conductive substrate, an electron transport layer, a hole blocking layer, and a metal electrode; Wherein, the self-assembled monolayer, the interface modification layer, the perovskite light absorption layer, the electron transport layer, the hole blocking layer, and the metal electrode are sequentially stacked on the conductive substrate.

[0055] In the embodiment of the present application, other functional layers may also be included. The required functional layers may be introduced according to actual needs to achieve specific functions. The conductive substrate includes one or more of FTO glass, ITO glass, and a flexible ITO conductive substrate. The material of the hole blocking layer may be BCP (Bathocuproine, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), and the preparation method of the hole blocking layer may include one or more of a slit coating method, a spin coating method, and a scraping method. The thickness of the hole blocking layer may be 8-15nm (for example, 8nm, 10nm, 12nm, 15nm). The electron transport layer may be made of titanium oxide (TiO2), tin oxide (SnO2), zinc oxide (ZnO), fullerene (C 60), graphene, fullerene derivatives (PCBM) and other one or more n-type semiconductor materials, the electron transport layer can be prepared by deposition methods including but not limited to electron beam evaporation, thermal evaporation, magnetron sputtering, atomic layer deposition, spin coating, scraping and the like. The thickness of the electron transport layer can be 20-40nm (for example, 20nm, 30nm, 40nm). Metal electrode: gold, palladium, silver, titanium, chromium, nickel, aluminum, copper, indium tin oxide (ITO), indium zinc oxide (IZO) and the like can be used. The thickness of the metal electrode can be 60-100nm (for example, 60nm, 80nm, 100nm).

[0056] In the embodiments of the present application, various performances of the perovskite solar cell are improved by introducing an acetophenone oxime interface modification layer between the self-assembled monolayer and the perovskite light absorption layer. The method has the advantages of simple preparation process, low material cost, obvious passivation effect, and obvious effect of improving the wettability of the self-assembled monolayer. The method is applicable to both single-molecule self-assembled materials containing phosphate groups and single-molecule self-assembled materials containing carboxylic acid groups, and is conducive to commercial production.

[0057] The embodiment of the present application also provides a method for preparing a perovskite solar cell, comprising: sequentially preparing a self-assembled monolayer, an interface modification layer, and a perovskite light absorption layer on a conductive substrate; Wherein, the material of the interface modification layer includes acetophenone oxime.

[0058] In the embodiments of the present application, various performances of the perovskite solar cell are improved by introducing an acetophenone oxime interface modification layer between the self-assembled monolayer and the perovskite light absorption layer. The method has the advantages of simple preparation process, low material cost, obvious passivation effect, and obvious effect of improving the wettability of the self-assembled monolayer. The method is applicable to both single-molecule self-assembled materials containing phosphate groups and single-molecule self-assembled materials containing carboxylic acid groups, and is conducive to commercial production.

[0059] In an optional embodiment, after preparing the self-assembled monolayer and before preparing the interface modification layer, the method further includes performing a first annealing; the annealing temperature of the first annealing is 100-120° C. (for example, 100° C., 110° C., 120° C.), and the annealing time is 10-15 min (for example, 10 min, 11 min, 12 min, 13 min, 14 min, 15 min); And / or, after preparing the interface modification layer and before preparing the perovskite light absorption layer, the method further comprises performing a second annealing; the annealing temperature of the second annealing is 100-120° C. (for example, 100° C., 110° C., 120° C.), and the annealing time is 10-15 min (for example, 10 min, 11 min, 12 min, 13 min, 14 min, 15 min); And / or, after preparing the perovskite light absorbing layer, before preparing other functional layers on the perovskite light absorbing layer, it also includes performing a third annealing; the annealing temperature of the third annealing is 100~150℃ (for example, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃), and the annealing time is 15~35min (for example, 15min, 20min, 25min, 30min, 35min).

[0060] In the embodiments of the present application, the annealing process of the self-assembled monolayer is optimized, so that the contact between the self-assembled monolayer and the acetophenone oxime interface modification layer can be optimized, and the wettability of the self-assembled monolayer can be effectively improved, so as to facilitate the formation of a dense and high-crystalline perovskite light absorption layer, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell; the annealing process of the interface modification layer is optimized, so that the contact between the self-assembled monolayer and the perovskite light absorption layer can be optimized, and the effective injection and transmission of holes can be promoted, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell; the annealing process of the perovskite light absorption layer is optimized, so that the crystallization quality and morphology of the prepared perovskite light absorption layer can be improved, which is beneficial to improving the photoelectric conversion rate of the perovskite solar cell.

[0061] The following specific examples further illustrate the present application, but should not be construed as limiting the present application. Without departing from the spirit and substance of the present application, modifications or replacements made to the methods, steps or conditions of the present application are within the scope of the present application.

[0062] Example 1 A perovskite solar cell, such as Figure 1 As shown, it includes: a conductive substrate 1, a self-assembled monolayer 2, an interface modification layer 3, a perovskite light absorption layer 4, an electron transport layer 5, a hole blocking layer 6, and a metal electrode 7 which are stacked in sequence.

[0063] The specific preparation process of perovskite solar cells is as follows: Step 100: Pretreatment of the conductive substrate 1: Using FTO (fluorine-doped SnO2 conductive glass) glass as the conductive substrate 1, the conductive substrate 1 is cleaned; Step 101: placing the conductive substrate 1 in an ultrasonic cleaning instrument, and ultrasonically cleaning the conductive substrate 1 with deionized water, isopropyl alcohol, and ethanol in sequence, each cleaning step lasting 20 minutes, and using a nitrogen (N2) air gun to blow dry the conductive substrate 1 to obtain a cleaned conductive substrate 1; Step 102: treating the cleaned conductive substrate 1 with UV-zone (ultraviolet ozone) for 10 minutes to obtain a substrate to be used; Step 200: Preparation of self-assembled monolayer 2 Step 201: dissolving Me-4PACZ ([4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid) in ethanol, stirring, and preparing a Me-4PACZ solution with a concentration of 0.6 mg / ml; Step 202: Spin coating the Me-4PACZ solution on the substrate to be used at a coating speed of 3000 rpm to obtain a first target substrate; Step 203: annealing the first target substrate at 100° C. for 10 min to form a self-assembled monolayer 2 with a thickness of 10 nm; Step 300: Preparation of interface modification layer 3 Step 301: dissolving acetophenone oxime in an ethanol solution, stirring, and preparing 2 ml of acetophenone oxime solution with a concentration of 0.8 mg / ml; Step 302: spin-coating the acetophenone oxime solution onto the self-assembled monolayer 2 at a rotation speed of 3000 rpm to obtain a second target substrate; Step 303: annealing the second target substrate at 100° C. for 10 min to form an interface modification layer 3 with a thickness of 10 nm; Step 400: Preparation of perovskite light absorption layer 4 Step 401: dissolving 1.6 mol of FAPbI3 perovskite solution in 1 ml of a solvent having a volume ratio of DMF:NMP=4:1, and stirring for 2 h to obtain a perovskite precursor solution; Step 402: using a one-step spin coating method, the perovskite precursor solution is spin coated on the interface modification layer 3 at a coating speed of 5000 rpm for 30 seconds, and 300 microliters of anisole is quickly added dropwise on the surface of the perovskite layer 5 seconds before the end of the spin coating deposition to form a perovskite wet film, thereby obtaining a third target substrate; Step 403: performing annealing treatment on the third target substrate at a temperature of 150° C. for 15 min to form a perovskite light absorption layer 4 with a thickness of 500 nm; Step 500: Preparation of electron transport layer 5 Step 501: Evaporate a C film with a thickness of 30 nm on the perovskite light absorption layer 4 at a rate of 0.5 Å / s. 60 (fullerene) layer as electron transport layer 5; Step 600: Preparation of hole blocking layer 6 Step 601: a BCP (Bathocuproine, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) layer with a thickness of 6 nm is deposited on the electron transport layer 5 at a rate of 0.5 Å / s as a hole blocking layer 6; Step 700: Preparation of metal electrode 7 Step 701: Using a thermal evaporation gold film coating method, a 110 nm thick silver electrode is deposited on the hole blocking layer 6 as the metal electrode 7, thereby obtaining the perovskite solar cell. The SEM image of the prepared perovskite light absorption layer is shown in FIG. Figure 2 As shown, see Figure 2 It can be seen that the prepared perovskite light absorption layer has good wettability, uniform and dense grain size distribution, and high film quality.

[0064] Example 2-Example 5 The perovskite solar cells of Examples 2 to 5 were prepared by referring to the preparation method of Example 1, except that the concentrations of acetophenone oxime in the acetophenone oxime solution prepared in step 301 were different. The concentrations of acetophenone oxime in Examples 2 to 5 are shown in Table 1.

[0065] Example 6-Example 7 The perovskite solar cells of Examples 6 and 7 were prepared by referring to the preparation method of Example 1, except that the thickness of the interface modification layer was different. The thickness of acetophenone oxime in Examples 6 and 7 is shown in Table 1.

[0066] Example 8-Example 11 The perovskite solar cells of Examples 8 to 11 were prepared by referring to the preparation method of Example 1, with the only difference being that the type of SAM and / or the amount of SAM added were different when preparing the self-assembled monolayer 2. The data on the type of SAM and the amount of SAM added in Examples 8 to 11 are shown in Table 1.

[0067] Example 12 The perovskite solar cell of Example 12 is prepared by referring to the preparation method of Example 1, except that step 203 of Example 12 is: annealing the first target substrate at 90° C. for 15 min to form a self-assembled monolayer 2 with a thickness of 10 nm.

[0068] Embodiment 13 The perovskite solar cell of Example 13 is prepared by referring to the preparation method of Example 1, except that step 203 of Example 13 is: annealing the first target substrate at 130° C. for 10 min to form a self-assembled monolayer 2 with a thickness of 10 nm.

[0069] Embodiment 14 The perovskite solar cell of Example 14 was prepared by referring to the preparation method of Example 1, except that step 303 of Example 14 was: annealing the second target substrate at 90° C. for 15 min to form an interface modification layer 3 with a thickness of 10 nm.

[0070] Embodiment 15 The perovskite solar cell of Example 15 is prepared by referring to the preparation method of Example 1, except that step 303 of Example 15 is: annealing the second target substrate at 130° C. for 10 min to form an interface modification layer 3 with a thickness of 10 nm.

[0071] Example 16 The perovskite solar cell of Example 16 is prepared by referring to the preparation method of Example 1, except that step 403 of Example 16 is: annealing the third target substrate at a temperature of 90° C. for 35 min to form a perovskite light absorption layer 4 with a thickness of 500 nm.

[0072] Embodiment 17 The perovskite solar cell of Example 17 is prepared by referring to the preparation method of Example 1, except that step 403 of Example 17 is: annealing the third target substrate at a temperature of 160° C. for 15 min to form a perovskite light absorption layer 4 with a thickness of 500 nm.

[0073] Comparative Example 1 The perovskite solar cell of Comparative Example 1 was prepared by referring to the preparation method of Example 1, except that the interface modification layer 3 was not prepared, that is, the perovskite solar cell of Comparative Example 1 was not provided with the interface modification layer 3. The SEM image of the prepared perovskite light absorption layer is as follows: Figure 3 As shown, see Figure 3 It can be seen that the prepared perovskite light absorption layer has poor wettability, resulting in uneven grain size distribution and poor density. Rod-shaped PbI2 can also be seen, and the film quality is low.

[0074] Table 1 Parameters of the embodiment Table 1

[0075] The following is a performance test of the perovskite solar cells provided in Examples 1-17 of the present application and Comparative Example 1. The test results are shown in Table 2.

[0076] Table 2 Performance test results of perovskite solar cells of Examples 1-17 and Comparative Example 1

[0077] Referring to the battery performance test results of Examples 1-17 and Comparative Example 1, it can be seen that the acetophenone oxime interface modification layer is introduced between the self-assembled monolayer and the perovskite light absorption layer. The carboxyl groups and other groups in the acetophenone oxime interact with each other, which can well improve the problem of poor wettability of the self-assembled monolayer caused by the SAM molecular material, and can effectively alleviate the uneven coverage of the perovskite film, so as to facilitate the formation of a dense and high-crystalline perovskite light absorption layer. At the same time, the unsaturated N atoms in the oxime group can also passivate the defects at the interface between the perovskite light absorption layer and the self-assembled monolayer, and can also react with free Pb + Coordination is carried out to improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of perovskite solar cells.

[0078] Referring to the battery performance test results of Examples 1 and 6-7, it can be seen that optimizing the thickness of the interface modification layer can optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, improve the extraction and transmission efficiency of holes, and thus improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0079] Referring to the battery performance test results of Examples 1-5, it can be seen that optimizing the concentration of acetophenone oxime can optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, promote the effective injection and transmission of holes, and thus improve the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0080] Referring to the battery performance test results of Examples 1 and 8-9, it can be seen that optimizing the concentration of SAM can effectively improve the wettability of the self-assembled monolayer, facilitate the formation of a dense and high-crystalline perovskite light absorption layer, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0081] Referring to the battery performance test results of Examples 1 and 12-17, it can be seen that optimizing the annealing process of the self-assembled monolayer can optimize the contact between the self-assembled monolayer and the acetophenone oxime interface modification layer, effectively improve the wettability of the self-assembled monolayer, and facilitate the formation of a dense and high-crystalline perovskite light absorption layer, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell; optimizing the annealing process of the interface modification layer can optimize the contact between the self-assembled monolayer and the perovskite light absorption layer, promote the effective injection and transmission of holes, thereby improving the short-circuit current density, open-circuit voltage and photoelectric conversion efficiency of the perovskite solar cell; optimizing the annealing process of the perovskite light absorption layer can improve the crystallization quality and morphology of the prepared perovskite light absorption layer, which is beneficial to improving the photoelectric conversion rate of the perovskite solar cell.

[0082] The embodiment of the present application may provide a photovoltaic cell assembly, including the above-mentioned perovskite solar cell; and / or The perovskite solar cell prepared by the above method has the same advantages as the above perovskite solar cell.

[0083] The embodiment of the present application can provide a photovoltaic system, including the above-mentioned photovoltaic cell assembly. The advantages of the above-mentioned photovoltaic cell assembly are also possessed by the photovoltaic system, which will not be repeated here. The above-mentioned photovoltaic system has a wide range of applications, not only limited to photovoltaic power stations, such as ground power stations, rooftop power stations and water power stations, but also includes various equipment and devices that use solar energy to generate electricity, such as user solar power supplies, solar street lights, solar cars and solar buildings. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited to this, that is to say, the photovoltaic system can be used in all fields where solar energy is required for power generation. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a junction box and an inverter. The photovoltaic array may be an array combination of multiple photovoltaic components. For example, multiple photovoltaic components may form multiple photovoltaic arrays. The photovoltaic array is connected to a junction box. The junction box can converge the current generated by the photovoltaic array. The converged current flows through the inverter and is converted into the alternating current required by the mains power grid and then connected to the mains network to realize solar power supply.

[0084] It should be noted that the terms "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The orientation words "inside" and "outside" refer to the inside and outside relative to the outline of each component itself. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Therefore, the exemplary term "above..." can include both "above..." and "below..." orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used here are interpreted accordingly.

[0085] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0086] It should also be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this application refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when describing a specific feature, structure or characteristic in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0087] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0088] It should also be noted that the above are only preferred embodiments of the present application, and the patent protection scope of the present application is not limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A perovskite solar cell, characterized in that: include: A self-assembled monolayer, an interface modification layer and a perovskite light absorption layer are stacked in sequence; the material of the interface modification layer includes acetophenone oxime.

2. The perovskite solar cell according to claim 1, characterized in that The thickness of the interface modification layer is 0.5-15 nm.

3. The perovskite solar cell according to claim 2, characterized in that: The thickness of the interface modification layer is 1-10 nm.

4. The perovskite solar cell according to claim 1, characterized in that: The interface modification layer is formed based on an acetophenone oxime solution; the acetophenone oxime solution comprises acetophenone oxime and an organic solvent; wherein the organic solvent comprises one or more of ethanol and isopropanol.

5. The perovskite solar cell according to claim 1, characterized in that: The concentration of the acetophenone oxime in the acetophenone oxime solution is 0.2-1.5 mg / ml.

6. The perovskite solar cell according to claim 5, characterized in that: The concentration of the acetophenone oxime in the acetophenone oxime solution is 0.4-1.2 mg / ml.

7. The perovskite solar cell according to claim 1, characterized in that: The material of the self-assembled monolayer includes: one or more of a single-molecule self-assembled material containing a phosphoric acid group and a single-molecule self-assembled material containing a carboxylic acid group.

8. The perovskite solar cell according to claim 1, characterized in that: The self-assembled monolayer is formed based on a SAM solution; the SAM solution includes SAM and a polar solvent; wherein the polar solvent includes one or more of ethanol and isopropanol, and the SAM includes: one or more of a single-molecule self-assembled material containing a phosphate group and a single-molecule self-assembled material containing a carboxylic acid group.

9. The perovskite solar cell according to claim 8, characterized in that: The concentration of SAM in the SAM solution is 0.2-1.0 mg / ml.

10. The perovskite solar cell according to claim 1, characterized in that: The perovskite light absorbing layer is formed from a perovskite precursor solution; The perovskite precursor solution comprises: a perovskite material and a solvent; Wherein, the perovskite material includes any one of FAMAPbI, FACsPbI3, and FAMACsPbI3; The solvent includes any one of a mixed solution of N,N-dimethylformamide and dimethyl sulfoxide and a mixed solution of γ-butyrolactone and N-methylpyrrolidone; the volume ratio of N,N-dimethylformamide to dimethyl sulfoxide in the mixed solution of N,N-dimethylformamide and dimethyl sulfoxide is 3-5:1; the volume ratio of γ-butyrolactone to N-methylpyrrolidone in the mixed solution of γ-butyrolactone and N-methylpyrrolidone is 3-5:

1.

11. The perovskite solar cell according to claim 1, characterized in that: It also includes a conductive substrate, an electron transport layer, a hole blocking layer, and a metal electrode; Wherein, the self-assembled monolayer, the interface modification layer, the perovskite light absorption layer, the electron transport layer, the hole blocking layer, and the metal electrode are sequentially stacked on the conductive substrate.

12. A method for preparing a perovskite solar cell, characterized in that: include: A self-assembled monolayer, an interface modification layer, and a perovskite light absorption layer are sequentially prepared on a conductive substrate; Wherein, the material of the interface modification layer includes acetophenone oxime.

13. The method for preparing a perovskite solar cell according to claim 12, characterized in that: After preparing the self-assembled monolayer and before preparing the interface modification layer, the method further comprises performing a first annealing; the annealing temperature of the first annealing is 100-120° C., and the annealing time is 10-15 min; And / or, after preparing the interface modification layer and before preparing the perovskite light absorption layer, the method further comprises performing a second annealing; the annealing temperature of the second annealing is 100-120° C., and the annealing time is 10-15 min; And / or, after preparing the perovskite light absorbing layer and before preparing other functional layers on the perovskite light absorbing layer, it also includes performing a third annealing; the annealing temperature of the third annealing is 100-150° C., and the annealing time is 15-35 min.

14. A photovoltaic cell assembly, characterized in that: A perovskite solar cell comprising any one of claims 1 to 11; and / or A perovskite solar cell prepared by the method according to any one of claims 12 to 13.

15. A photovoltaic system, characterized in that: Comprising the photovoltaic cell assembly as claimed in claim 14.

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