Perovskite solar cell, preparation method thereof and laminated cell

Abstract

The invention relates to a perovskite solar cell, a preparation method thereof and a laminated cell. The perovskite solar cell comprises a first electrode, a hole transport layer, a perovskite light absorption layer and a second electrode, the hole transport layer is located between the first electrode and the perovskite light absorption layer, the perovskite light absorption layer is located between the hole transport layer and the second electrode, and the hole transport layer comprises a compound shown in the formula (I). According to the perovskite solar cell provided by the invention, the compound shown in the formula (I) is adopted as a hole transport layer material, in the compound shown in the formula (I), dibenzocarbazolyl and bithiophene are connected to serve as a main chain, a phosphate group is introduced, the thermal decomposition temperature of the compound is high, and the thermal stability of the perovskite solar cell is effectively improved; and meanwhile, the compound is relatively high in mobility and beneficial to hole extraction and transmission, so that the photoelectric conversion efficiency of the solar cell can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a perovskite solar cell and a preparation method thereof, and a stacked cell. Background Art

[0002] Perovskite solar cells have garnered widespread attention in both science and industry, demonstrating significant potential for scalable future applications. Perovskite solar cells have a typical sandwich structure consisting of a light-absorbing, photosensitive perovskite layer and an adjacent hole-transport layer (HTL). Conventional HTLs suffer from poor thermal stability.

[0003] Therefore, it is necessary to improve the traditional technology. Summary of the Invention

[0004] Based on this, the present application provides a perovskite solar cell with good thermal stability, a preparation method thereof, and a stacked cell.

[0005] The technical solution of this application to solve the above technical problems is as follows.

[0006] In a first aspect, the present application provides a perovskite solar cell, comprising a first electrode, a hole transport layer, a perovskite light absorbing layer, and a second electrode, wherein the hole transport layer is located between the first electrode and the perovskite light absorbing layer, and the perovskite light absorbing layer is located between the hole transport layer and the second electrode, and the hole transport layer comprises a compound represented by formula (I):

[0007]

[0008] Wherein, L is selected from one of C1~C6 alkylene groups;

[0009] Each occurrence of R1 is independently selected from substituted or unsubstituted C1~C 18 Alkyl, substituted or unsubstituted C1~C 18 Alkoxy, substituted or unsubstituted C1~C 18 Alkylthio, halogen atom, trifluoromethyl, hydroxyl, mercapto, cyano, amino and substituted or unsubstituted C6~C 18 One of the aromatic groups;

[0010] Each of the substituted substituents is independently selected from one of C1-C4 alkyl, amino, halogen, nitro, hydroxyl, thiol, carboxyl and cyano;

[0011] m are independently selected from integers of 0 to 4;

[0012] n is an integer from 10 to 1000.

[0013] In some embodiments, in the perovskite solar cell, L is selected from one of C2-C4 alkylene groups.

[0014] In some embodiments, in the perovskite solar cell, the hole transport layer comprises at least one of 2PA-DCz and 4PA-DCz:

[0015] .

[0016] A second aspect of the present application provides a method for preparing a perovskite solar cell, comprising the following steps:

[0017] preparing a hole transport layer on the first electrode;

[0018] preparing a perovskite light absorbing layer on a side of the hole transport layer away from the first electrode;

[0019] Prepare a second electrode on a side of the perovskite light absorbing layer away from the hole transport layer;

[0020] The hole transport layer includes a compound represented by formula (I):

[0021]

[0022] Wherein, L is selected from one of C1~C6 alkylene groups;

[0023] Each occurrence of R1 is independently selected from substituted or unsubstituted C1~C 18 Alkyl, substituted or unsubstituted C1~C 18 Alkoxy, substituted or unsubstituted C1~C 18 Alkylthio, halogen atom, trifluoromethyl, hydroxyl, mercapto, cyano, amino and substituted or unsubstituted C6~C 18 One of the aromatic groups;

[0024] Each of the substituted substituents is independently selected from one of C1-C4 alkyl, amino, halogen, nitro, hydroxyl, thiol, carboxyl and cyano;

[0025] m are independently selected from integers of 0 to 4;

[0026] n is an integer from 10 to 1000.

[0027] In some embodiments, in the method for preparing a perovskite solar cell, the preparation of the compound represented by formula (I) comprises the following steps:

[0028] The compound represented by formula (II) and the compound represented by formula (III) are subjected to a Suzuki coupling reaction to prepare the compound represented by formula (IV);

[0029] The compound represented by formula (IV) is subjected to a hydrolysis reaction to prepare the compound represented by formula (I);

[0030]

[0031] Wherein, X is a halogen atom;

[0032] Each occurrence of R2 is independently selected from C1~C8 alkyl.

[0033] In some embodiments, in the method for preparing a perovskite solar cell, the method satisfies at least one of the following characteristics:

[0034] (1) In the Suzuki coupling reaction, the molar ratio of the compound represented by formula (II) to the compound represented by formula (III) is 1:(1-1.2);

[0035] (2) The Suzuki coupling reaction is carried out in the presence of a first catalyst, wherein the first catalyst comprises tetrakis(triphenylphosphine)palladium;

[0036] (3) The Suzuki coupling reaction is carried out in the presence of a first base, wherein the first base comprises potassium carbonate;

[0037] (4) The temperature of the Suzuki coupling reaction is 80°C to 90°C.

[0038] In some embodiments, in the method for preparing a perovskite solar cell, the preparation of the compound represented by formula (II) comprises the following steps:

[0039] The compound represented by formula (V) is subjected to a first substitution reaction with a triester of phosphite to prepare a compound represented by formula (II);

[0040]

[0041] Y is a halogen atom;

[0042] Optionally, the preparation method satisfies at least one of the following characteristics:

[0043] (1) The phosphite triester includes triethyl phosphite;

[0044] (2) The molar ratio of the triester phosphite to the compound represented by formula (V) is (25-100):1;

[0045] (3) The temperature of the first substitution reaction is 140°C to 150°C.

[0046] In some embodiments, in the method for preparing a perovskite solar cell, the preparation of the compound represented by formula (V) comprises the following steps:

[0047] The compound represented by formula (VI) and the compound represented by formula (VII) are subjected to a second substitution reaction to prepare a compound represented by formula (V);

[0048] ;

[0049] Optionally, the preparation method satisfies at least one of the following characteristics:

[0050] (1) The molar ratio of the compound represented by formula (VI) to the compound represented by formula (VII) is 1:(50-250);

[0051] (2) the second substitution reaction is carried out in the presence of a second catalyst, wherein the second catalyst comprises tetrabutylammonium bromide;

[0052] (3) the second substitution reaction is carried out in the presence of a second base, wherein the second base comprises potassium hydroxide;

[0053] (4) The temperature of the second substitution reaction is 65°C to 70°C.

[0054] In some embodiments, in the method for preparing a perovskite solar cell, the preparation of the compound represented by formula (VI) comprises the following steps:

[0055] The compound represented by formula (VIII) is subjected to a halogenation reaction to prepare the compound represented by formula (VI);

[0056] ;

[0057] Optionally, the preparation method satisfies at least one of the following characteristics:

[0058] (1) The halogenation reaction is carried out in the presence of a halogenating agent, wherein the halogenating agent comprises N-halogenated succinimide, and the molar ratio of the halogenating agent to the compound represented by formula (VIII) is (2.1-3):1;

[0059] (2) The temperature of the halogenation reaction is -5°C to 0°C.

[0060] A third aspect of the present application provides a stacked cell comprising a bottom cell and a top cell, wherein the top cell comprises the perovskite solar cell provided in the first aspect or the perovskite solar cell prepared by the preparation method of the perovskite solar cell provided in the second aspect, and the bottom cell comprises a crystalline silicon cell.

[0061] The perovskite solar cell provided in the present application uses a compound represented by formula (I) as a hole transport layer material. In the compound represented by formula (I), a dibenzocarbazolyl group is connected to a bithiophene group as the main chain, and a phosphate group is introduced. The thermal decomposition temperature of the compound is relatively high, which can effectively improve the thermal stability of the perovskite solar cell; at the same time, the mobility of the compound is relatively high, which is conducive to the extraction and transport of holes, thereby effectively improving the photoelectric conversion efficiency of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present application and to more fully understand the present application and its beneficial effects, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0063] Figure 1 A schematic structural diagram of an inverted perovskite battery provided in one embodiment;

[0064] Figure 2 This is the H NMR spectrum of compound 4 prepared in Example 1;

[0065] Figure 3 This is the H NMR spectrum of compound 8 prepared in Example 2;

[0066] Figure 4 Scanning electron microscopy image of the perovskite film surface prepared on 2PA-DCz;

[0067] Figure 5 Scanning electron microscopy image of the cross section of the perovskite film prepared on 2PA-DCz;

[0068] Figure 6 Scanning electron microscope image of the perovskite film surface prepared on 4PA-DCz;

[0069] Figure 7 Scanning electron microscope image of the cross section of the perovskite film prepared on 4PA-DCz.

[0070] Reference numerals:

[0071] 10: Inverse perovskite cell; 11: Transparent conductive electrode; 12: Hole transport layer; 13: Perovskite light absorption layer; 14: Electron transport layer; 15: Metal electrode. DETAILED DESCRIPTION

[0072] The present application will be further described in detail below in conjunction with the embodiments and examples. It should be understood that these embodiments and examples are only intended to illustrate the present application and are not intended to limit the scope of the present application. The purpose of providing these embodiments and examples is to provide a more thorough and comprehensive understanding of the disclosure of the present application.

[0073] It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various changes or modifications without violating the connotation of the present application, and the resulting equivalent forms also fall within the scope of protection of the present application. For example, features illustrated or described as part of one embodiment can be combined in a suitable manner in another embodiment to produce a new embodiment. In addition, in the description below, a large number of specific details are given in order to provide a more complete understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.

[0074] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing embodiments and examples only and are not intended to limit this application.

[0075] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0076] In this application, "plurality", "multiple", "multiple times", etc., unless otherwise specified, refer to a quantity greater than or equal to 2. For example, "one or more" means one or more than or equal to two.

[0077] As used herein, "combination thereof", "any combination thereof", "any combination thereof" and the like include all suitable combinations of any two or more of the listed items.

[0078] Herein, the “suitable” mentioned in “suitable combination”, “suitable method”, “any suitable method”, etc. shall be based on the ability to implement the technical solution of this application, solve the technical problems of this application, and achieve the expected technical effects of this application.

[0079] In this application, "further", "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be understood as limiting the scope of protection of this application.

[0080] In this application, the terms "first," "second," "third," "fourth," etc. in "the first aspect," "the second aspect," "the third aspect," "the fourth aspect," etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or quantity, nor should they be understood as implicitly indicating the importance or quantity of the indicated technical features. Furthermore, "first," "second," "third," "fourth," etc. serve only as non-exhaustive enumeration and description, and should be understood not to constitute a closed-ended limitation on quantity.

[0081] In this application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0082] In this application, when referring to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values within the numerical interval is deemed to be continuous and includes the two numerical endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two numerical endpoints. Unless otherwise specified, when a numerical interval refers only to integers within the numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe a feature or characteristic, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical ranges disclosed herein should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. "Numerical interval" allows for a broad range of numerical interval types including percentage intervals, ratio intervals, and ratio intervals.

[0083] Unless otherwise specified, the temperature parameters in this application allow for both constant temperature treatment and temperature fluctuations within a certain temperature range. It should be understood that the constant temperature treatment allows for temperature fluctuations within the accuracy range of instrument control. Fluctuations within ranges such as ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are permitted.

[0084] In this application, the term "room temperature" or "normal temperature" generally refers to 4°C to 35°C, for example, 20°C ± 5°C. In some embodiments of this application, "room temperature" or "normal temperature" refers to 10°C to 30°C. In some embodiments of this application, "room temperature" or "normal temperature" refers to 20°C to 30°C.

[0085] In this application, when referring to a range of units, if the unit is only after the right endpoint, it means that the units of the left and right endpoints are the same. For example, 3~5h means that the units of the left endpoint "3" and the right endpoint "5" are both hours.

[0086] All documents mentioned in this application are cited as references in this application, just as each document is cited as a reference individually. Unless they conflict with the invention purpose and / or technical solution of this application, the cited documents involved in this application are cited in their entirety and for all purposes. When cited documents are involved in this application, the definitions of relevant technical features, terms, nouns, phrases, etc. in the cited documents are also cited. When cited documents are involved in this application, the examples and preferred embodiments of the cited relevant technical features may also be incorporated into this application as references, but are limited to the ability to implement this application. It should be understood that when the cited content conflicts with the description in this application, the present application shall prevail or be adaptively amended according to the description in this application.

[0087] The mass or weight of the relevant components mentioned in the examples of this application may not only refer to the specific content of each component, but also represent the proportional relationship of the mass or weight of each component. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the examples of this application, it is within the scope disclosed in the examples of this application. Specifically, the mass or weight described in the examples of this application may be units known in the chemical industry such as μg, mg, g, and kg.

[0088] Conventional HTLs doped with spiro-OMeTAD, lithium bis(trifluoromethanesulfonyl) salt (LiTFSI), or 4-tert-butylpyridine (tBP) suffer from severe morphological deformation upon exposure to thermal environments.

[0089] One embodiment of the present application provides a perovskite solar cell, comprising a first electrode, a hole transport layer, a perovskite light absorbing layer, and a second electrode, wherein the hole transport layer is located between the first electrode and the perovskite light absorbing layer, and the perovskite light absorbing layer is located between the hole transport layer and the second electrode, and the hole transport layer comprises a compound represented by formula (I):

[0090]

[0091] Wherein, L is selected from one of C1~C6 alkylene groups;

[0092] Each occurrence of R1 is independently selected from substituted or unsubstituted C1~C 18 Alkyl, substituted or unsubstituted C1~C 18 Alkoxy, substituted or unsubstituted C1~C 18 Alkylthio, halogen atom, trifluoromethyl, hydroxyl, mercapto, cyano, amino and substituted or unsubstituted C6~C 18 One of the aromatic groups;

[0093] Each substituted substituent is independently selected from one of C1-C4 alkyl, amino, halogen, nitro, hydroxyl, thiol, carboxyl and cyano;

[0094] m are independently selected from integers of 0 to 4;

[0095] n is an integer from 10 to 1000.

[0096] A compound represented by formula (I) (D-π type organic polymer) is used as a hole transport layer material. In the compound represented by formula (I), a dibenzocarbazolyl group is connected to a bithiophene group as a main chain, and a phosphate group is introduced. The thermal decomposition temperature of the compound is relatively high, which can effectively improve the thermal stability of the perovskite solar cell. At the same time, the mobility of the compound is relatively high, which is conducive to the extraction and transport of holes, thereby effectively improving the photoelectric conversion efficiency of the solar cell.

[0097] It is understood that C1~C6 alkylene refers to an alkylene group containing 1 to 6 carbon atoms, including but not limited to at least one of methylene (-CH2-), ethylene (-CH2CH2-), propylene (-CH2CH2CH2-), butylene (-CH2CH2CH2CH2-), pentylene (-CH2CH2CH2CH2CH2-), hexylene (-CH2CH2CH2CH2CH2CH2-), etc.; C1~C 18 Alkyl refers to a group with 1 to 18 carbon atoms, which can be straight chain or branched chain. 18 The number of carbon atoms includes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, and 18; in some examples, any two of these values can be used as end values within the range, the same below; C1~C 18 Alkoxy refers to an alkoxy group containing 1 to 18 carbon atoms; C1~C 18 Alkylthio refers to an alkylthio group containing 1 to 18 carbon atoms; C6~C 18 Aryl refers to an aromatic ring with 6 to 18 carbon atoms; m refers to the number of substituents, including 0, 1, 2, 3 or 4, which respectively replace the hydrogen on the benzene ring. When m is 0, it means that there are no other substituents on the benzene ring; it can also be understood that when m is 2 to 4, each R1 can be the same or different.

[0098] In some examples, in the perovskite solar cell, L is selected from one of C2-C4 alkylene groups. Alternatively, L is selected from one of ethylene and butylene groups.

[0099] In some examples, in perovskite solar cells, each occurrence of R1 is independently selected from one of a C1-C4 alkyl group, a C1-C4 alkoxy group, a C1-C4 alkylthio group, a halogen group, a trifluoromethyl group, a hydroxyl group, a thiol group, a cyano group, and an amino group. It is understood that the C1-C4 alkyl group, the C1-C4 alkoxy group, and the C1-C4 alkylthio group are unsubstituted by other groups.

[0100] In some examples, in perovskite solar cells, the hole transport layer includes at least one of 2PA-DCz and 4PA-DCz:

[0101] .

[0102] 2PA-DCz and 4PA-DCz have good solubility and film-forming properties, high hole mobility, and energy levels that match perovskite. Using them as undoped hole transport materials in inverse perovskite solar cells can achieve good photoelectric conversion efficiency.

[0103] 2PA-DCz and 4PA-DCz have good wettability with perovskite precursor solvents and can promote the crystallization and film formation of perovskite.

[0104] In some of these examples, the thickness of the hole transport layer in perovskite solar cells is 20 nm to 100 nm.

[0105] It is understood that the compound represented by formula (I) can be used alone as a hole transport material in the hole transport layer, or the compound represented by formula (I) can be used in combination with other hole transport materials, for example, in combination with carbazole hole materials (2PACZ, MEO-2PACZ, 4PACz and Me-4PACz, etc.).

[0106] In some of these examples, in perovskite solar cells, the perovskite light-absorbing layer includes ABX3, where A is a monovalent cation, B is a divalent metal cation, and X is a halogen anion.

[0107] Optionally, the monovalent cation includes at least one of a cesium ion, a methylamine ion, an ethylamine ion, a formamidine ion, a benzylamine ion, and a phenylethylamine ion.

[0108] Optionally, the divalent metal cations include at least one of lead ions, tin ions, and copper ions.

[0109] Optionally, the halogen anion includes at least one of a bromide ion, a chloride ion, and an iodide ion.

[0110] In some of these examples, the perovskite solar cell also includes an electron transport layer, which is located between the perovskite light-absorbing layer and the second electrode.

[0111] Optionally, the electron transport layer includes at least one of metal oxide, fullerene and derivatives thereof.

[0112] Furthermore, the metal oxide includes but is not limited to at least one of tin oxide, zinc oxide, etc.; fullerene and its derivatives include at least one of C60, PC61BM, PC71BM, etc.

[0113] At least one of the first electrode and the second electrode is a transparent conductive electrode (transparent conductive oxide TCO), and the other is one of a transparent conductive electrode and a metal electrode; optionally, the transparent conductive electrode includes but is not limited to at least one of indium tin oxide (ITO), fluorine-doped tin oxide (FTO), indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), antimony-doped tin oxide (ATO), etc.; the metal electrode includes but is not limited to at least one of chromium (Cr), gold (Au), silver (Ag), copper (Cu), aluminum (Al), etc.

[0114] Perovskite solar cells (PSCs) include formal perovskite cells (upright) and inverted perovskite cells (inverted); formal perovskite cells consist of a transparent conductive oxide, an electron transport layer, a perovskite light absorption layer, a hole transport layer, and a metal electrode from bottom to top; inverted perovskite cells reverse the positions of the electron transport layer and the hole transport layer, and their structure, from bottom to top, is usually a transparent conductive oxide, a hole transport layer, a perovskite light absorption layer, an electron transport layer, and a metal electrode.

[0115] In some examples, the perovskite solar cell is an inverted perovskite cell. That is, the first electrode is a transparent conductive electrode. Furthermore, the second electrode is a metal electrode; optionally, the second electrode includes chromium and copper.

[0116] In inverse perovskite cells, the compound represented by formula (I) serves as an important hole transport material (HTMs) between the perovskite layer and the transparent electrode. It is not only responsible for the extraction and transport of holes and blocking the flow of electrons, but also directly affects the crystallization and film formation of the perovskite, playing a decisive role in improving cell performance and achieving large-scale commercial applications.

[0117] See also Figure 1 In some examples, the inverse perovskite cell 10 includes a transparent conductive electrode 11 (first electrode), a hole transport layer 12, a perovskite light absorbing layer 13, an electron transport layer 14 and a metal electrode 15 (second electrode) stacked in sequence.

[0118] The perovskite solar cell provided in this application has high photoelectric conversion efficiency and high thermal stability, and is suitable for large-area inverse perovskite cells.

[0119] It can be understood that the perovskite solar cell provided above can be prepared by the following method for preparing a perovskite solar cell. The method for preparing a perovskite solar cell corresponds to the parameters in the perovskite solar cell. For example, the groups involved in the raw materials in the method for preparing the compound represented by formula (I) correspond to the groups in the compound represented by formula (I).

[0120] An embodiment of the present application provides a method for preparing a perovskite solar cell, comprising the following steps:

[0121] preparing a hole transport layer on the first electrode;

[0122] A perovskite light absorbing layer is prepared on a side of the hole transport layer away from the first electrode;

[0123] A second electrode is prepared on the side of the perovskite light absorbing layer away from the hole transport layer;

[0124] The hole transport layer includes a compound represented by formula (I):

[0125]

[0126] Wherein, L is selected from one of C1~C6 alkylene groups;

[0127] Each occurrence of R1 is independently selected from substituted or unsubstituted C1~C 18 Alkyl, substituted or unsubstituted C1~C 18 Alkoxy, substituted or unsubstituted C1~C 18 Alkylthio, halogen atom, trifluoromethyl, hydroxyl, mercapto, cyano, amino and substituted or unsubstituted C6~C 18 One of the aromatic groups;

[0128] Each substituted substituent is independently selected from one of C1-C4 alkyl, amino, halogen, nitro, hydroxyl, thiol, carboxyl and cyano;

[0129] m are independently selected from integers of 0 to 4;

[0130] n is an integer from 10 to 1000.

[0131] In some examples, in the method for preparing a perovskite solar cell, the preparation of the compound represented by formula (I) includes the following steps:

[0132] Step S100: subjecting the compound represented by formula (II) and the compound represented by formula (III) (2,2'-dithiophene-5,5'-diboronic acid dipinacolyl) to a Suzuki coupling reaction to prepare a compound represented by formula (IV);

[0133] Step S200: hydrolyzing the compound represented by formula (IV) to prepare the compound represented by formula (I);

[0134]

[0135] Wherein, X is a halogen atom;

[0136] Each occurrence of R2 is independently selected from C1~C8 alkyl.

[0137] It is understood that halogen atoms include but are not limited to F, Cl, Br, and I.

[0138] In some examples, in step S100, in the Suzuki coupling reaction, the molar ratio of the compound represented by formula (II) to the compound represented by formula (III) is 1:(1-1.2). It is understood that the molar ratio of the compound represented by formula (II) to the compound represented by formula (III) includes but is not limited to 1:1, 1:1.1, and 1:1.2.

[0139] In some examples, in step S100, the Suzuki coupling reaction is performed in the presence of a first catalyst. Optionally, the first catalyst comprises tetrakis(triphenylphosphine)palladium. Optionally, the molar ratio of the first catalyst to the compound represented by formula (IV) is (0.01-0.1):1.

[0140] In some examples, in step S100, the Suzuki coupling reaction is carried out in the presence of a first base. Optionally, the first base comprises potassium carbonate. Optionally, the molar ratio of the first base to the compound represented by formula (IV) is (4-10):1.

[0141] In some examples, in step S100, the temperature of the Suzuki coupling reaction is 80° C. to 90° C. It is understood that the temperature of the Suzuki coupling reaction includes but is not limited to 80° C., 81° C., 82° C., 83° C., 84° C., 85° C., 86° C., 87° C., 88° C., 89° C., and 90° C., for example, 85° C. to 90° C. Furthermore, the time of the Suzuki coupling reaction is 8 h to 16 h.

[0142] In some examples, in step S100, the Suzuki coupling reaction is carried out in the presence of a solvent, wherein the solvent includes toluene, ethanol, and water; further, the volume ratio of toluene, ethanol, and water is 2-3:1-2:1.

[0143] In some examples, in step S100, after the Suzuki coupling reaction is completed, post-treatment is further included: the reaction solution is cooled to room temperature, the reaction solution is extracted with DCM, the organic phase is dried over anhydrous Mg2SO4, filtered, distilled under reduced pressure, purified by silica gel chromatography, and dried in vacuo.

[0144] In some examples, in step S100, the preparation of the compound represented by formula (II) includes:

[0145] In step S110, the compound represented by formula (V) and a triester of phosphite are subjected to a first substitution reaction to prepare a compound represented by formula (II);

[0146]

[0147] Y is a halogen atom.

[0148] In some examples, in step S110 , the triester phosphite includes triethyl phosphite.

[0149] In some examples, in step S110, the molar ratio of the triester phosphite to the compound represented by formula (V) is (25-100):1. It is understood that the molar ratio of the triester phosphite to the compound represented by formula (V) includes but is not limited to 25:1, 30:1, 35:1, 40:1, 45:1, 50:1, 55:1, 60:1, 65:1, 70:1, 75:1, 80:1, 85:1, 90:1, 95:1, and 100:1. For example, the molar ratio of the triester phosphite to the compound represented by formula (V) is (25-80):1.

[0150] In some examples, in step S110, the temperature of the first substitution reaction is 140° C. to 150° C. It is understood that the temperature of the first substitution reaction includes, but is not limited to, 140° C., 141° C., 142° C., 143° C., 144° C., 145° C., 146° C., 147° C., 148° C., 149° C., and 150° C. Furthermore, the time for the first substitution reaction is 12 h to 16 h.

[0151] In some examples, after the first substitution reaction in step S110 is completed, post-treatment is further included: cooling the reaction solution to room temperature, extracting the reaction solution with DCM, drying the organic phase with anhydrous Mg2SO4, filtering, distilling under reduced pressure, purifying with a silica gel chromatography column, and vacuum drying.

[0152] In some examples, in step S110 , the first substitution reaction is performed under an inert atmosphere.

[0153] It is understood that the inert atmosphere includes but is not limited to nitrogen and argon.

[0154] In some examples, in step S110, the preparation of the compound represented by formula (V) includes:

[0155] Step S111: subjecting the compound represented by formula (VI) and the compound represented by formula (VII) to a second substitution reaction to prepare a compound represented by formula (V);

[0156] .

[0157] In some examples, in step S111, the molar ratio of the compound represented by formula (VI) to the compound represented by formula (VII) is 1:(50-250).

[0158] In some examples, in step S111, the second substitution reaction is carried out in the presence of a second catalyst, wherein the second catalyst comprises tetrabutylammonium bromide. Optionally, the molar ratio of the second catalyst to the compound represented by formula (VI) is (0.1-0.2):1.

[0159] In some examples, in step S111, the second substitution reaction is carried out in the presence of a second base, wherein the second base comprises potassium hydroxide (KOH). Optionally, the molar ratio of the second base to the compound represented by formula (VI) is (5-10):1.

[0160] In some examples, in step S111 , the temperature of the second substitution reaction is 65° C. to 70° C. Furthermore, the time of the second substitution reaction is 12 h to 24 h.

[0161] In some examples, in step S111 , the second substitution reaction is performed under an inert atmosphere.

[0162] In some examples, after the second substitution reaction in step S111 is completed, post-treatment is further included: quenching the reaction with water, extracting the reaction solution with DCM, drying the organic phase with anhydrous Mg2SO4, filtering, distilling under reduced pressure, purifying with a silica gel chromatography column, and vacuum drying.

[0163] In some examples, in step S111, the preparation of the compound represented by formula (VI) includes:

[0164] Step S1111: subjecting the compound represented by formula (VIII) to a halogenation reaction to prepare the compound represented by formula (VI);

[0165] .

[0166] In some examples, in step S1111, the halogenation reaction is performed in the presence of a halogenating reagent.

[0167] Optionally, the halogenating agent comprises N-halosuccinimide. Further, the halogenating agent comprises N-bromosuccinimide (NBS).

[0168] Optionally, the molar ratio of the halogenating agent to the compound represented by formula (VIII) is (2.1-3):1.

[0169] Optionally, the temperature of the halogenation reaction is -5°C to 0°C.

[0170] In some examples, step S1111 includes the following steps:

[0171] The compound represented by formula (VIII) and THF were mixed and degassed, flushed with N2 gas, stirred at 0°C for 10 min~15 min, and then a THF solution of NBS was added dropwise, and the reaction was continued at 0°C for 3~5 hours.

[0172] Furthermore, the post-treatment of step S1111 includes: quenching the reaction with water, extracting the reaction solution with DCM, drying the organic phase with anhydrous Mg2SO4, filtering, distilling under reduced pressure, and purifying by column chromatography.

[0173] In some examples, in step S200, the hydrolysis reaction includes:

[0174] Step S210: Under the protection of an inert gas, the compound represented by formula (IV) is dissolved in an organic solvent, trimethylsilyl bromide is added dropwise, and the mixture is stirred for reaction; after the reaction is completed, the solvent is removed to obtain an intermediate compound (solid powder).

[0175] Optionally, in step S210, the molar ratio of the compound represented by formula (IV) to trimethylsilyl bromide is 1:(8-15).

[0176] Optionally, in step S210, the organic solvent includes 1,4-dioxane; further, the temperature of 1,4-dioxane is 25° C. to 30° C.

[0177] Optionally, in step S210, the solvent is removed using a rotary evaporator.

[0178] Step S220: dissolving the solid powder intermediate compound prepared in step S210 in alcohol, adding water, and stirring for 10 to 16 hours.

[0179] Optionally, in step S220, the mixture is dissolved in methanol at room temperature; optionally, water is added until the mixture becomes opaque.

[0180] Optionally, in step S220, after stirring for 10 to 16 hours, post-treatment is performed: the reaction solution is filtered and washed with water, the crude product is dissolved in THF, reprecipitated in acetone, and filtered to obtain the compound represented by formula (I).

[0181] In some of these examples, the preparation routes of the compounds represented by formula (I) are as follows:

[0182] .

[0183] The raw materials for preparing the compound represented by formula (I) are low in cost, the preparation process is simple, and it is suitable for industrial production.

[0184] In some of the examples, in the method for preparing a perovskite solar cell, a method for preparing a hole transport layer includes a solution method; further, the solution method includes a solution spin coating method.

[0185] In some examples, in the method for preparing a perovskite solar cell, forming a hole transport layer on the first electrode includes the following steps:

[0186] dissolving the compound represented by formula (I) in an organic solvent to obtain a mixed solution;

[0187] The mixed solution is spin-coated onto the first electrode and annealed.

[0188] Optionally, the organic solvent includes at least one of dimethyl sulfoxide, N,N'-dimethylformamide, toluene, chlorobenzene and dichloromethane.

[0189] It can be understood that the compound represented by formula (I) has good solubility in dimethyl sulfoxide, N,N'-dimethylformamide, toluene, chlorobenzene and dichloromethane.

[0190] Optionally, the concentration of the compound represented by formula (I) in the mixed solution is 3 mg / mL to 15 mg / mL.

[0191] Optionally, the spin coating rotation speed is 4000 rpm to 5000 rpm.

[0192] Optionally, the annealing temperature is 90° C. to 110° C.

[0193] In some of these examples, the method for preparing a solar cell further includes, before preparing the second electrode, a step of preparing an electron transport layer on a side of the perovskite light absorbing layer away from the hole transport layer.

[0194] It can be understood that the present application does not limit the method of preparing the perovskite light absorbing layer and the electron transport layer, including but not limited to the solution method; and does not limit the method of preparing the second electrode, including but not limited to evaporation.

[0195] In some examples, the method for preparing a solar cell includes the following steps:

[0196] (1) Cleaning: ultrasonically clean the transparent conductive electrode TCO with water, acetone, and ethanol in sequence, optionally for 15 to 20 minutes; then use an N2 air gun to blow off the residual solvent on the surface of the transparent conductive electrode, and then perform oxygen plasma treatment, optionally for 10 to 15 minutes; then transfer the transparent conductive electrode TCO to a nitrogen glove box;

[0197] (2) Preparation of a hole transport layer: dissolving the compound represented by formula (I) in an organic solvent, optionally, the organic solvent includes chlorobenzene; dropping the obtained mixed solution onto the transparent conductive electrode TCO, and spin coating, optionally, the spin coating time is 20 s to 30 s; then annealing at 90°C to 110°C, optionally, the annealing time is 10 min to 20 min;

[0198] (3) Preparation of perovskite light absorbing layer: The TCO / hole transport layer obtained above is cooled to room temperature, and preheated at 130°C to 140°C, optionally for 3 min to 5 min; the perovskite precursor solution is placed on the surface of the hole transport layer away from the ITO, and spin-coated, optionally for 20 s to 30 s; and then annealed at 90°C to 100°C, optionally for 10 min to 15 min to prepare a perovskite light absorbing layer, optionally with a thickness of 500 nm to 1000 nm. nm; wherein the perovskite precursor solution comprises 3-halogenated benzyl ammonium iodide, methylammonium chloride and lead iodide; the 3-halogenated benzyl ammonium iodide is selected from 3-bromobenzylammonium iodide and / or 3-chlorobenzylammonium iodide; the solvent of the perovskite precursor solution includes but is not limited to at least one of DMF and DMSO, optionally, the solvent includes DMF and DMSO, further, the molar ratio of DMF to DMSO is 4 to 6:1;

[0199] (4) Preparation of an electron transport layer: an electron transport solution is placed on the surface of the perovskite light absorbing layer away from the hole transport layer, spin-coated, and annealed to prepare an electron transport layer; optionally, the electron transport material in the electron transport solution includes PC61BM, and further, the concentration of the electron transport material is 15 mg / mL to 25 mg / mL; optionally, the spin coating rate is 1000 rpm to 1500 rpm, and the spin coating time is 30 s to 50 s; optionally, the thickness of the electron transport layer is 100 nm to 500 nm;

[0200] (5) Preparation of electrodes: The substrate is placed in a vacuum evaporation chamber, and a metal is evaporated onto the electron transport layer; optionally, the metal includes Cr and Au; further, the thickness of Cr is 6 nm to 10 nm, and the thickness of Au is 80 nm to 100 nm, thereby obtaining an inverse quasi-two-dimensional perovskite solar cell.

[0201] One embodiment of the present application provides a stacked cell, comprising a bottom cell and a top cell, wherein the top cell comprises the above-mentioned perovskite solar cell or a perovskite solar cell prepared by the above-mentioned method for preparing a perovskite solar cell, and the bottom cell comprises a crystalline silicon cell.

[0202] The tandem cell provided in the present application, including the above-mentioned perovskite solar cell, can provide the tandem cell with better thermal stability and higher photoelectric conversion performance.

[0203] It is understood that tandem cells include, but are not limited to, two-terminal tandem cells, three-terminal tandem cells, and four-terminal tandem cells. Furthermore, tandem cells include, but are not limited to, perovskite cells stacked with crystalline silicon cells, perovskite cells stacked with perovskite cells, and perovskite cells stacked with thin-film cells. Thin-film cells include, but are not limited to, perovskite thin-film solar cells, copper indium selenide thin-film solar cells, gallium arsenide thin-film solar cells, and cadmium sulfide thin-film solar cells; crystalline silicon cells include, but are not limited to, PERC cells (passivated emitter and rear cell), IBC cells (interdigitated back contact cell), TOPCon cells (tunneling oxide passivated contact cell), HJT cells (heterojunction cell), and HBC cells (heterojunction back contact cell).

[0204] One embodiment of the present application provides a photovoltaic module, including the solar cell provided above, a solar cell prepared by the method for preparing a solar cell provided above, or a laminated cell provided above.

[0205] Some examples of PV panels include:

[0206] A cell string is formed by electrically connecting a plurality of the above-mentioned solar cells or perovskite cells produced by the above-mentioned solar cell production method, or by electrically connecting a plurality of the above-mentioned stacked cells;

[0207] Encapsulation film, used to cover the surface of the battery string; and

[0208] The cover plate is used to cover the surface of the packaging film facing away from the battery string.

[0209] It is understood that solar cells or laminated cells are electrically connected in the form of a whole cell or multiple slices to form multiple cell strings, and multiple cell strings are electrically connected in series and / or parallel. Furthermore, solar cells or laminated cells can be whole cells or sliced cells. Sliced cells refer to cells formed by cutting a complete whole cell.

[0210] In some examples, multiple battery strings may be electrically connected via conductive ribbons.

[0211] In some examples, the encapsulation film includes a first encapsulation layer and a second encapsulation layer, the first encapsulation layer covers one of the front and back sides of the battery, and the second encapsulation layer covers the other of the front and back sides of the battery; further, the first encapsulation layer and the second encapsulation layer can independently include at least one of organic encapsulation films such as polyvinyl butyral (PVB) film, ethylene-vinyl acetate copolymer (EVA) film, polyethylene octene co-elastomer (POE) film and polyethylene terephthalate (PET) film.

[0212] In some examples, the cover plate may be a glass cover plate, a plastic cover plate, or other cover plate with a light-transmitting function.

[0213] The present application will be described in further detail below in conjunction with specific implementation methods, but the implementation methods of the present application are not limited thereto.

[0214] Yields refer to molar yields.

[0215] Example 1

[0216] (1) Compound 1 (4 mmol) and dichloromethane (20 mL) were added to a round-bottom flask, followed by N-bromosuccinimide (8.48 mmol). The mixture was heated to room temperature and stirred overnight. The reaction was quenched with water, extracted with dichloromethane, and the organic layers were combined and dried over anhydrous magnesium sulfate. The organic solvent was then removed by rotary evaporation to obtain a crude product. The product was purified by flash column chromatography using petroleum ether / dichloromethane (10:1 by volume) as the eluent to obtain compound 2 (yield 90%).

[0217]

[0218] (2) Compound 2 (3 mmol) was added to a double-necked flask, followed by tetrabutylammonium bromide (0.3 mmol) dissolved in dibromoethane (35 mL). A 50% aqueous potassium hydroxide solution (5 mL) was then added dropwise. The mixture was heated to 65°C and stirred overnight. The reaction was quenched with water and extracted with dichloromethane. The organic layer was combined with anhydrous magnesium sulfate and dried. The organic solvent was then removed by rotary evaporation to obtain a crude product. Purification was performed by silica gel column chromatography using a 10 / 1 petroleum ether / dichloromethane eluent to obtain compound 3 (1.31 g, 82% yield).

[0219]

[0220] (3) Compound 3 (2.5 mmol) and triethyl phosphite (10 mL) were added to a double-necked flask, the mixture was heated to 160°C, and stirred overnight under a nitrogen atmosphere. The organic solvent was then removed by rotary evaporation to obtain compound 4 (1.13 g, yield 74%). The H NMR spectrum of compound 4 is shown in FIG. Figure 2 shown.

[0221]

[0222] (4) Compound 4 (1 mmol), compound 5 (1 mmol), tetrakis(triphenylphosphine)palladium (0.05 mmol), and potassium carbonate (6 mmol) were added to a double-necked flask with toluene, ethanol, and water (volume ratio of 2:1:1). The reaction was carried out at 85°C for 12 hours. The mixture was cooled to room temperature and extracted with DCM. The organic phase was dried over anhydrous Mg2SO4, filtered, and evaporated under reduced pressure. Finally, compound 6 (0.32 g, 58% yield) was purified by column chromatography (PE:DCM = 4:1) to obtain compound 6.

[0223]

[0224] (5) 1.2 g of compound 6 was added to anhydrous 1,4-dioxane (10 mL) at room temperature, and trimethylsilyl bromide (20 mmol) was added dropwise, followed by stirring overnight. 1,4-dioxane was removed using a rotary evaporator to obtain a solid powder, which was dissolved in methanol (10 mL) at room temperature, and deionized water was then added dropwise until the mixture became opaque, and stirred for another 12 hours. The crude product was collected by filtration and washed with deionized water. The crude product was dissolved in THF (5 mL), reprecipitated in acetone (20 mL), and filtered to obtain the final product, 2PA-DCz (1.01 g, 91% yield).

[0225]

[0226] Example 2

[0227] (1) Compound 1 (4 mmol) and dichloromethane (20 mL) were added to a round-bottom flask, followed by the addition of N-bromosuccinimide (8.48 mmol). The mixture was heated to room temperature and stirred overnight. The reaction was quenched with water, extracted with dichloromethane, and the organic layers were combined and dried over anhydrous magnesium sulfate. The organic solvent was then removed by rotary evaporation to obtain a crude product. The product was purified by flash column chromatography using petroleum ether / dichloromethane (10:1, by volume) as the eluent to obtain compound 2 (yield 90%).

[0228]

[0229] (2) Compound 2 (3 mmol) was added to a double-necked flask, followed by tetrabutylammonium bromide (0.3 mmol) dissolved in dibromobutane (35 mL), and then a 50% aqueous potassium hydroxide solution (5 mL) was added dropwise. The mixture was heated to 65°C and stirred overnight. The reaction was quenched with water and extracted with dichloromethane. The organic layer was combined with anhydrous magnesium sulfate and dried, and the organic solvent was removed by rotary evaporation to obtain a crude product. Purification was performed by silica gel column chromatography using a 10 / 1 petroleum ether / dichloromethane eluent to obtain compound 7 (1.41 g, 83% yield).

[0230]

[0231] (3) Compound 7 (2.5 mmol) and triethyl phosphite (20 mL) were added to a double-necked flask, the mixture was heated to 160°C, and stirred overnight under a nitrogen atmosphere. The organic solvent was then removed by rotary evaporation to obtain the crude product compound 8 (yield 79%). The H NMR spectrum of compound 8 is shown in FIG. Figure 3 shown.

[0232]

[0233] (4) Compound 4 (1 mmol), compound 5 (1 mmol), tetrakis(triphenylphosphine)palladium (0.05 mmol), and potassium carbonate (6 mmol) were added to a double-necked flask. The solvent was toluene, ethanol, and water (volume ratio of 2:1:1). The reaction was carried out at 85°C for 12 hours. After cooling to room temperature, the mixture was extracted with DCM. The organic phase was dried over anhydrous Mg2SO4, filtered, and distilled under reduced pressure. Finally, it was purified by column chromatography (PE:DCM = 4:1) to obtain compound 9 (0.39 g) with a yield of 61%.

[0234]

[0235] (5) 1.2 g of compound 9 was added to anhydrous 1,4-dioxane (10 mL) at room temperature, and trimethylsilyl bromide (20 mmol) was added dropwise, followed by stirring overnight. 1,4-dioxane was removed using a rotary evaporator to obtain a solid powder. The solid powder was dissolved in methanol (10 mL) at room temperature, and deionized water was added dropwise until the mixture became opaque, and then stirred for another 12 hours. The crude product was collected by filtration and washed with deionized water. The crude product was dissolved in THF (5 mL), reprecipitated in acetone (20 mL), and filtered to obtain the final product 4PA-DCz (0.64 g, 54% yield).

[0236]

[0237] Comparative Example 1

[0238] The method is basically the same as Example 1, except that compound 1 in step (1) of Example 1 is replaced by compound 10, and compound 11 is finally prepared:

[0239] .

[0240] Comparative Example 2

[0241] The method is basically the same as Example 1, except that compound 5 in step (4) of Example 1 is replaced by compound 12, and compound 13 is finally prepared:

[0242] .

[0243] Thermogravimetric analysis was performed using a thermogravimetric analyzer, with N2 selected as the program protection gas and the purge flow rate set at 20 cm 3 / min, with the starting temperature set at 25°C and the heating rate set at 10°C / min. Analysis of the measured curves revealed that the thermal decomposition temperatures (Td, 5% weight loss) of 2PA-DCz and 4PA-DCz were 278°C and 261°C, respectively, indicating that 2PA-DCz and 4PA-DCz had high thermal decomposition temperatures and good thermal stability.

[0244] Perovskite films were prepared on ITO coated with the HTMs to be tested (2PA-DCz and 4PA-DCz). The surface morphology and cross-section of the films were scanned using a scanning electron microscope. The scanning electron microscope images of the surface of the perovskite film prepared on 2PA-DCz are shown in Figure 2. Figure 4 As shown, the scanning electron microscope image of the cross section of the perovskite film prepared on 2PA-DCz is as follows Figure 5 As shown in the scanning electron microscope image of the perovskite film surface prepared on 4PA-DCz Figure 6 As shown in the scanning electron microscope image of the cross section of the perovskite film prepared on 4PA-DCz Figure 7 As shown in the figure, the perovskite film grown based on 2PA-DCz and 4PA-DCz has a relatively uniform crystal size and is tightly arranged without obvious boundary defects. This indicates that 2PA-DCz and 4PA-DCz can promote the crystallization growth of perovskite films during the preparation of PSCs devices, promote the complete coverage of the hole transport layer by the perovskite film, and effectively suppress the charge recombination defects caused by the direct contact between the electron transport layer and the hole transport layer, which is beneficial to the improvement of the photovoltaic efficiency of PSCs devices.

[0245] Perovskite solar cells were prepared using the compounds prepared in each example and comparative example as hole transport materials:

[0246] (1) Cleaning: Use deionized water, acetone and ethanol to ultrasonically clean the ITO glass sheet for 15-20 minutes, then use a N2 air gun to blow dry the residual solvent on the ITO surface, and then perform oxygen plasma treatment for 10-15 minutes. Then, transfer the ITO glass sheet to a nitrogen glove box;

[0247] (2) Preparation of hole transport layer: Weigh 3-15 mg of hole transport material and completely dissolve it in 1 mL of chlorobenzene solution. Take an appropriate amount of solution and evenly drop it onto the ITO glass substrate. Spin coat at 4000-5000 rpm for 20-30 seconds, and then anneal at 90-110°C for 10 minutes.

[0248] (3) Preparation of perovskite light-absorbing layer: The ITO / hole transport layer substrate obtained above was cooled to room temperature, preheated at 130°C to 140°C for 3 to 5 minutes, 50 μl of perovskite solution (3-chlorobenzylammonium iodide, methylammonium chloride, lead iodide mixed in DMF and DMSO) was taken and spread all over the ITO / hole transport layer substrate, and spin-coated at 3000-5000 rpm for 20-30 seconds, and then annealed at 90°C to 100°C for 10 minutes to prepare a perovskite light-absorbing layer;

[0249] (4) Preparation of electron transport layer: The ITO / hole transport layer / perovskite substrate obtained above was cooled to room temperature, PC61BM was prepared into a 15 mg / mL solution, and then 40 μl of PC61BM solution was taken to cover the ITO / hole transport layer / perovskite substrate, spin-coated at 1000 rpm for 30-50 seconds, and annealed at 100°C for 10 minutes;

[0250] (5) Preparation of electrodes: Place the above substrate in a vacuum evaporation chamber, and evaporate Cr (6 nm) and Au (80 nm) on the PC61BM layer respectively to obtain the desired inverse quasi-two-dimensional perovskite solar cell.

[0251] Photoelectric conversion efficiency: 0.02V s under AM 1.5G lighting conditions -1 The JV curve of the best device measured by forward and reverse scanning, detailed photovoltaic index Voc, short-circuit current density (Jsc), fill factor (FF) and photoelectric conversion efficiency (PCE) are shown in Table 1.

[0252] Table 1

[0253]

[0254] As can be seen from Table 1, the photoelectric conversion efficiency of the solar cells prepared by using 2PA-DCz and 4PA-DCz as hole transport layer materials is relatively high.

[0255] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0256] The embodiments described above only express several implementation methods of the present application, which are convenient for understanding the technical solutions of the present application in a specific and detailed manner, but they cannot be understood as limiting the scope of protection of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several variations and improvements can be made, which all fall within the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of this application shall be based on the content of the attached claims, and the description can be used to interpret the content of the claims.

Claims

1. A perovskite solar cell, characterized in that: The invention comprises a first electrode, a hole transport layer, a perovskite light absorbing layer, and a second electrode, wherein the hole transport layer is located between the first electrode and the perovskite light absorbing layer, the perovskite light absorbing layer is located between the hole transport layer and the second electrode, and the hole transport layer comprises a compound represented by formula (I): Wherein, L is selected from one of C1~C6 alkylene groups; Each occurrence of R1 is independently selected from substituted or unsubstituted C1~C 18 Alkyl, substituted or unsubstituted C1~C 18 Alkoxy, substituted or unsubstituted C1~C 18 Alkylthio, halogen atom, trifluoromethyl, hydroxyl, mercapto, cyano, amino and substituted or unsubstituted C6~C 18 One of the aromatic groups; Each of the substituted substituents is independently selected from one of C1-C4 alkyl, amino, halogen, nitro, hydroxyl, thiol, carboxyl and cyano; m are independently selected from integers of 0 to 4; n is an integer from 10 to 1000.

2. The perovskite solar cell according to claim 1, wherein L is selected from one of C2~C4 alkylene groups.

3. The perovskite solar cell according to claim 1 or 2, wherein: The hole transport layer includes at least one of 2PA-DCz and 4PA-DCz: 。 4. A method for preparing a perovskite solar cell, characterized in that: The following steps are involved: preparing a hole transport layer on the first electrode; preparing a perovskite light absorbing layer on a side of the hole transport layer away from the first electrode; Prepare a second electrode on a side of the perovskite light absorbing layer away from the hole transport layer; The hole transport layer includes a compound represented by formula (I): Wherein, L is selected from one of C1~C6 alkylene groups; Each occurrence of R1 is independently selected from substituted or unsubstituted C1~C 18 Alkyl, substituted or unsubstituted C1~C 18 Alkoxy, substituted or unsubstituted C1~C 18 Alkylthio, halogen atom, trifluoromethyl, hydroxyl, mercapto, cyano, amino and substituted or unsubstituted C6~C 18 One of the aromatic groups; Each of the substituted substituents is independently selected from one of C1-C4 alkyl, amino, halogen, nitro, hydroxyl, thiol, carboxyl and cyano; m are independently selected from integers of 0 to 4; n is an integer from 10 to 1000.

5. The method for preparing a perovskite solar cell according to claim 4, wherein: The preparation of the compound represented by formula (I) comprises the following steps: The compound represented by formula (II) and the compound represented by formula (III) are subjected to a Suzuki coupling reaction to prepare the compound represented by formula (IV); The compound represented by formula (IV) is subjected to a hydrolysis reaction to prepare the compound represented by formula (I); Wherein, X is a halogen atom; Each occurrence of R2 is independently selected from C1~C8 alkyl.

6. The method for preparing a perovskite solar cell according to claim 5, wherein: The preparation method satisfies at least one of the following characteristics: (1) In the Suzuki coupling reaction, the molar ratio of the compound represented by formula (II) to the compound represented by formula (III) is 1:(1-1.2); (2) The Suzuki coupling reaction is carried out in the presence of a first catalyst, wherein the first catalyst comprises tetrakis(triphenylphosphine)palladium; (3) The Suzuki coupling reaction is carried out in the presence of a first base, wherein the first base comprises potassium carbonate; (4) The temperature of the Suzuki coupling reaction is 80°C to 90°C.

7. The method for preparing a perovskite solar cell according to claim 5 or 6, wherein: The preparation of the compound represented by formula (II) comprises the following steps: The compound represented by formula (V) is subjected to a first substitution reaction with a triester of phosphite to prepare a compound represented by formula (II); Y is a halogen atom; Optionally, the preparation method satisfies at least one of the following characteristics: (1) The phosphite triester includes triethyl phosphite; (2) The molar ratio of the triester phosphite to the compound represented by formula (V) is (25-100):1; (3) The temperature of the first substitution reaction is 140°C to 150°C.

8. The method for preparing a perovskite solar cell according to claim 7, wherein: The preparation of the compound represented by formula (V) comprises the following steps: The compound represented by formula (VI) and the compound represented by formula (VII) are subjected to a second substitution reaction to prepare a compound represented by formula (V); ； Optionally, the preparation method satisfies at least one of the following characteristics: (1) The molar ratio of the compound represented by formula (VI) to the compound represented by formula (VII) is 1:(50-250); (2) the second substitution reaction is carried out in the presence of a second catalyst, wherein the second catalyst comprises tetrabutylammonium bromide; (3) the second substitution reaction is carried out in the presence of a second base, wherein the second base comprises potassium hydroxide; (4) The temperature of the second substitution reaction is 65°C to 70°C.

9. The method for preparing a perovskite solar cell according to claim 8, wherein: The preparation of the compound represented by formula (VI) comprises the following steps: The compound represented by formula (VIII) is subjected to a halogenation reaction to prepare the compound represented by formula (VI); ； Optionally, the preparation method satisfies at least one of the following characteristics: (1) The halogenation reaction is carried out in the presence of a halogenating agent, wherein the halogenating agent comprises N-halogenated succinimide, and the molar ratio of the halogenating agent to the compound represented by formula (VIII) is (2.1-3):1; (2) The temperature of the halogenation reaction is -5°C to 0°C.

10. A stacked battery, characterized in that: The invention comprises a bottom cell and a top cell, wherein the top cell comprises a perovskite solar cell according to any one of claims 1 to 3 or a perovskite solar cell prepared by the preparation method of a perovskite solar cell according to any one of claims 4 to 9, and the bottom cell comprises a crystalline silicon cell.

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