Perovskite solar cell, laminated solar cell and photovoltaic module

Abstract

The invention provides a perovskite solar cell, a laminated solar cell and a photovoltaic module, the perovskite solar cell comprises a perovskite light absorption layer and a first charge transport layer arranged on one side of the perovskite light absorption layer, the first charge transport layer comprises a hole transport material, and the hole transport material comprises a compound represented by a formula I. According to the hole transport material in the perovskite solar cell provided by the invention, the film-forming property of a perovskite thin film can be improved, and then the stability and the photoelectric conversion efficiency of the perovskite solar cell are improved.

Description

Technical Field

[0001] This application relates to the technical field of solar cells, and particularly to a perovskite solar cell, a tandem solar cell, and a photovoltaic module. Background Art

[0002] A perovskite solar cell (PSCs) is a device that uses a perovskite-type organometallic halide semiconductor as a light-absorbing material to directly convert light energy into electrical energy through the photovoltaic effect; the hole transport layer (HTL) in its structure mainly functions to block electrons, enhance hole transport, and prevent quenching caused by direct contact between the perovskite active layer and the electrode. However, currently used hole transport materials, especially organic small-molecule hole transport materials, often have the problem of low tolerance to perovskite precursor solutions, resulting in poor film-forming properties of the perovskite film, and affecting the stability and photoelectric conversion efficiency of the battery. Summary of the Invention

[0003] Based on this, this application provides a perovskite solar cell, a tandem solar cell, and a photovoltaic module, which can improve the film-forming properties of the perovskite film, and then enhance the stability and photoelectric conversion efficiency of the perovskite solar cell.

[0004] The first aspect of this application provides a perovskite solar cell, including a perovskite light-absorbing layer, and a first charge transport layer disposed on one side of the perovskite light-absorbing layer, the first charge transport layer containing a hole transport material, and the hole transport material includes a compound represented by the following formula I:

[0005] Formula I

[0006] In formula I, A1 and A2 each independently selected from one of an O atom and an S atom.

[0007] In some embodiments of this application, the hole transport material includes at least one of the following formula I-1 and formula I-2:

[0008] Formula I-1

[0009] Formula I-2

[0010] In some embodiments of this application, the roughness of the surface of the perovskite light-absorbing layer adjacent to the first charge transport layer is less than 20 nm, and may be optionally 10 nm to 15 nm.

[0011] In some embodiments of this application, the hole transport material satisfies one or more of the following conditions:

[0012] (1) The decomposition temperature of the hole transport material is 225°C to 235°C;

[0013] (2) The carrier mobility of the hole transport material is 2.35×10 -4 cm 2 ·V -1 ·s -1 ~3.30×10 - 4 cm 2 ·V -1 ·s -1 ;

[0014] (3) The HOMO energy level of the hole transport material is -5.25 eV to -5.35 eV.

[0015] In some embodiments of the present application, the perovskite light-absorbing layer comprises a quasi-two-dimensional perovskite material, and the quasi-two-dimensional perovskite material includes (RNH3)2A1’ n1-1 B1’ n1 X1 3n1+1 , A’A2’ n2-1 B2’ n2 X2 3n2+1 and (GA)A3 n3 M n3 X3 3n3+1 or one or more of them;

[0016] wherein, R includes one or more of substituted or unsubstituted alkyl groups with a carbon atom number greater than or equal to 2, substituted or unsubstituted aryl groups, A1’, A2’ and A3 each independently include one or more of monovalent cations, A’ is an organic diamine cation, B1’, B2’ and M each independently include one or more of divalent cations, X1, X2 and X3 each independently include one or more of halogen ions, GA is a guanidinium ion, and n1, n2 and n3 are each independently greater than 1;

[0017] Optionally, the monovalent cation includes one or more of methylammonium ion, ethylammonium ion, propylammonium ion, butylammonium ion, pentylammonium ion, hexylammonium ion, formamidinium ion and imidazolium ion;

[0018] Optionally, the divalent cation includes Pb 2+ , Sn 2+ , Be 2+ , Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Zn 2+ , Ge 2+ , Fe 2+ , Co2+ and Cu 2+ one or more of;

[0019] Optionally, the organic diamine cation includes one or more of an ethylenediamine divalent cation, a butanediamine divalent cation, a benzenedimethyldiamine divalent cation, and a piperazine divalent cation.

[0020] In some embodiments of the present application, the perovskite solar cell further includes a second charge transport layer disposed on the other side of the perovskite light-absorbing layer, and the second charge transport layer contains an electron transport material.

[0021] In some embodiments of the present application, the perovskite solar cell further includes a first electrode and a second electrode; the first electrode is disposed on the side of the first charge transport layer away from the perovskite light-absorbing layer, and the second electrode is disposed on the side of the second charge transport layer away from the perovskite light-absorbing layer;

[0022] Optionally, the first electrode is a transparent electrode.

[0023] A second aspect of the present application provides a tandem solar cell, including a light-absorbing layer, a first carrier transport layer, and a second carrier transport layer, and the light-absorbing layer is disposed between the first carrier transport layer and the second carrier transport layer;

[0024] The light-absorbing layer includes a first light-absorbing layer, a composite layer, and a second light-absorbing layer stacked in sequence, and at least one of the first light-absorbing layer and the second light-absorbing layer is a perovskite layer;

[0025] One of the first carrier transport layer and the second carrier transport layer contains a hole transport material, and the hole transport material includes a compound represented by the following formula I:

[0026] Formula I,

[0027] In Formula I, A1 and A2 each independently selected from one of an O atom and an S atom.

[0028] In some embodiments of the present application, the first light-absorbing layer is adjacent to the first carrier transport layer, the first light-absorbing layer is a perovskite layer, and the first carrier transport layer contains the hole transport material.

[0029] A third aspect of the present application provides a photovoltaic module, including at least one of the perovskite solar cell according to the first aspect of the present application and the tandem solar cell according to the second aspect of the present application.

[0030] The hole transport material provided by this application combines carbazole-based phosphoric acid with phenylfluoreneamine groups (i.e., N-methoxyphenyl-dimethylfluorenamine group). After the combination of the two, they interact with each other, which can not only endow the hole transport material itself with good film-forming properties, but also have good tolerance and wettability to the perovskite precursor solution, reduce the morphological defects of pinholes in the perovskite light-absorbing layer formed adjacent to the hole transport material, reduce the interface electron trap density, improve the crystallization and film-forming properties and stability of the perovskite light-absorbing layer, and then facilitate the improvement of the stability and photoelectric conversion efficiency of the perovskite solar cell. Description of the Drawings

[0031] Figure 1 It is a schematic diagram of a perovskite solar cell according to an embodiment of this application.

[0032] Figure 2 It is the 1H nuclear magnetic resonance spectrum of the hole transport material Cz-1 prepared in Example 1.

[0033] Figure 3 It is the 1H nuclear magnetic resonance spectrum of the hole transport material Cz-2 prepared in Example 2.

[0034] Reference numerals: 11 perovskite light-absorbing layer; 10 first charge transport layer; 13 second charge transport layer; 12 first electrode; 16 second electrode. Detailed Embodiments

[0035] To facilitate the understanding of this application, the following will provide a more comprehensive description of this application. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of this application more thorough and comprehensive.

[0036] For simplicity, this application only explicitly discloses some numerical ranges. However, any lower limit can be combined with any upper limit to form a range not explicitly recorded; and any lower limit can be combined with other lower limits to form a range not explicitly recorded, and similarly any upper limit can be combined with any other upper limit to form a range not explicitly recorded. In addition, although not explicitly recorded, each point or single value between the range endpoints is included in this range. Thus, each point or single value can be used as its own lower or upper limit and combined with any other point or single value or combined with other lower or upper limits to form a range not explicitly recorded.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. It should be noted that unless otherwise stated, the term "and / or" used herein includes any and all combinations of one or more of the related listed items, "above" and "below" include the number itself, and "one or more" means two or more for "more than one".

[0038] In this document, when referring to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the selectable numerical values within this numerical interval is considered continuous, and includes the two numerical endpoints of this numerical interval (i.e., the minimum value and the maximum value), as well as each numerical value between these two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to the integers within this numerical interval, it includes the two endpoint integers of this numerical range, as well as each integer between the two endpoints, which is equivalent to directly listing each integer. When providing multiple numerical ranges to describe features or characteristics, 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 sub-ranges subsumed therein. The "numerical value" in this numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. The "numerical interval" allows for a broad inclusion of numerical interval types such as percentage intervals, ratio intervals, and ratio value intervals.

[0039] In this document, for a method process involving multiple steps, unless there are clear different descriptions in this document, the execution of these steps is not strictly restricted in order, and they can be executed in an order other than the described one. Moreover, any step can include multiple sub-steps or multiple stages. These sub-steps or stages do not necessarily need to be executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed alternately or simultaneously with other steps or a part of the sub-steps or stages of other steps.

[0040] The above application content of this application does not intend to describe every disclosed embodiment or every implementation mode in this application. The following description more specifically gives examples of exemplary embodiments. Throughout the application, guidance is provided through a series of embodiments, which can be used in various combinations. In each instance, the listing is only a representative group and should not be construed as exhaustive.

[0041] At present, the hole transport materials (HTMs) in perovskite solar cells are mainly divided into three categories: inorganic hole transport materials, organic small molecule hole transport materials, and organic polymer hole transport materials. Among them, organic small molecule hole transport materials have become the most common type in perovskite solar cells due to their advantages such as synthetic varieties, adjustable properties, high purity, and easy solution processing. However, due to the rigid structure of organic small molecule hole transport materials, their tolerance to perovskite precursor solutions is relatively low. As a result, the perovskite thin films formed adjacent to this small molecule hole transport material are prone to pinhole morphology defects, leading to poor film-forming properties, and the morphology is unstable under external stimuli. In addition, many small molecule hole transport materials require the addition of dopants during use. These factors have all posed obstacles to the large-scale commercialization of perovskite solar cells. To solve these technical problems, the inventors have proposed the following technical solutions in this application.

[0042] In a first aspect, this application provides a perovskite solar cell. Refer to Figure 1 , which includes a perovskite light-absorbing layer 11, and a first charge transport layer 10 disposed on one side of the perovskite light-absorbing layer 11. The first charge transport layer 10 contains a hole transport material, and the hole transport material includes a compound represented by the following formula I:

[0043] Formula I

[0044] In formula I, A1 and A2 each independently select one of an O atom and an S atom.

[0045] The hole transport material with the structure shown in formula I provided by this application combines carbazole-based phosphoric acid with phenylfluorenamine groups (i.e., N-methoxyphenyl-dimethylfluorenamine group). After the two are combined and interact with each other, it can not only endow the hole transport material itself with good film-forming properties, but also has good tolerance and wettability to the perovskite precursor solution, which can reduce the pinhole morphology defects in the perovskite light-absorbing layer formed adjacent to this hole transport material, reduce the interface electron trap density, and improve the crystallization film-forming properties and stability of the perovskite light-absorbing layer.

[0046] At the same time, due to the good film-forming properties of the hole transport material itself, and the interaction between the carbazole-based phosphoric acid and the phenylfluorenamine groups after combination, the hole transport material can have a relatively deep HOMO energy level and a high carrier mobility that match the perovskite light-absorbing layer. Therefore, this hole transport material does not require the addition of dopants during use and has good repeatability, which is conducive to the large-scale commercial application of perovskite solar cells. Generally speaking, the hole transport material with the structure shown in formula I is conducive to improving the stability and photoelectric conversion efficiency of perovskite solar cells.

[0047] In some embodiments, the hole transporting material includes at least one of the following formulas I-1 and I-2:

[0048] Formula I-1,

[0049] Formula I-2.

[0050] The hole transporting material including Formula I-1 and / or Formula I-2 has good film-forming property and thermal stability, good solubility in solvents, and good tolerance and wettability to the perovskite precursor solution. It can reduce the pinhole morphology defects in the perovskite light-absorbing layer formed adjacent to the hole transporting material, reduce the interface electron trap density, and improve the crystallization film-forming property and stability of the perovskite light-absorbing layer. At the same time, the hole transporting material has a relatively high carrier mobility, which is beneficial to the extraction and transport of holes. Thus, it is beneficial to comprehensively improve the stability and photoelectric conversion efficiency of the perovskite solar cell.

[0051] In some embodiments, the roughness of the surface of the perovskite light-absorbing layer adjacent to the first charge transporting layer is less than 20 nm, and can be optionally 10 nm to 15 nm. For example, the roughness can be 1 nm, 3 nm, 5 nm, 7 nm, 9 nm, 11 nm, 13 nm, 15 nm, 17 nm, 19 nm or within the range composed of any of the above values. Thus, the perovskite light-absorbing layer has a relatively small roughness, and the defect density of its pinhole morphology is small, which is beneficial to the improvement of the photoelectric conversion efficiency of the perovskite solar cell.

[0052] In some embodiments, the decomposition temperature of the hole transporting material is 225 °C to 235 °C. For example, the decomposition temperature of the hole transporting material can be 225 °C, 227 °C, 229 °C, 231 °C, 233 °C, 235 °C or within the range composed of any of the above values. Thus, the decomposition temperature of the hole transporting material is relatively high, having good thermal stability, which is beneficial to the improvement of the stability of the perovskite solar cell.

[0053] In some embodiments, the carrier mobility of the hole transporting material is 2.35×10 -4 cm 2 ·V -1 ·s -1 ~3.30×10 -4 cm 2 ·V -1 ·s -1 . For example, the carrier mobility of the hole transporting material can be 2.35×10 -4 cm 2 ·V -1 ·s -1 , 2.41×10-4 cm 2 ·V -1 ·s -1 ,2.52×10 -4 cm 2 ·V -1 ·s -1 ,2.63×10 -4 cm 2 ·V -1 ·s -1 ,2.74×10 -4 cm 2 ·V -1 ·s -1 ,2.85×10 -4 cm 2 ·V -1 ·s -1 ,2.96×10 -4 cm 2 ·V -1 ·s -1 ,3.07×10 -4 cm 2 ·V -1 ·s -1 ,3.18×10 -4 cm 2 ·V -1 ·s -1 ,3.29×10 -4 cm 2 ·V -1 ·s -1 ,3.30×10 -4 cm 2 ·V -1 ·s -1 or within the range composed of any of the above values. In this way, the hole transport material has a high carrier mobility, which is beneficial to the transport and extraction of holes, and then beneficial to the improvement of the photoelectric conversion efficiency of the perovskite solar cell.

[0054] In some embodiments, the HOMO energy level of the hole transport material is -5.25 eV to -5.35 eV. For example, the HOMO energy level of the hole transport material can be -5.25 eV, -5.27 eV, -5.29 eV, -5.31 eV, -5.33 eV, -5.35 eV or within the range composed of any of the above values. In this way, the hole transport material has a relatively deep HOMO energy level, which is beneficial to better match the energy levels of the perovskite light-absorbing layer, and then beneficial to the improvement of the photoelectric conversion efficiency of the perovskite solar cell.

[0055] In some embodiments, the perovskite light-absorbing layer comprises a quasi-two-dimensional perovskite material, and the quasi-two-dimensional perovskite material includes (RNH3)2A1’ n1-1 B1’ n1 X1 3n1+1 、A’A2’ n2-1 B2’ n2 X2 3n2+1 and (GA)A3 n3 M n3 X3 3n3+1 or one or more of them;

[0056] wherein, R includes one or more of substituted or unsubstituted alkyl groups with carbon atoms greater than or equal to 2, substituted or unsubstituted aryl groups, A1’, A2’ and A3 each independently include one or more of monovalent cations, A’ is an organic diamine cation, B1’, B2’ and M each independently include one or more of divalent cations, X1, X2 and X3 each independently include one or more of halogen ions, GA is a guanidinium ion, and n1, n2 and n3 are each independently greater than 1.

[0057] When the perovskite light-absorbing layer contains a quasi-two-dimensional perovskite material, the matching effect with the aforementioned hole transport material is better, and the hole transport material has a better improvement effect on the crystallization film-forming property and stability of the quasi-two-dimensional perovskite material.

[0058] It should be noted that the "quasi-two-dimensional perovskite material" described in this application refers to a low-dimensional semiconductor material between three-dimensional (3D) and two-dimensional (2D) perovskites, and its structure is composed of alternating inorganic perovskite layers and organic spacer cation layers, and its structural general formula is L2A y-1 B y X 3y+1 ; wherein, L is a long-chain organic spacer cation (such as PEA + 、BA + 、BDA 2+ ), A is a small molecule cation (such as MA + 、FA + 、Cs + ), B is a metal ion (such as Pb 2+ 、Sn 2+ ), X is a halogen ion (such as I - 、Br - 、Cl - ), y is the thickness of the inorganic layer ([BX6] 4- number of octahedral layers), usually 1 < y < ∞ (y = 1 is pure 2D, n → ∞ is 3D).

[0059] In some embodiments, the monovalent cation includes one or more of methylamino ion, ethylamino ion, propylamino ion, butylamino ion, pentylamino ion, hexylamino ion, formamidinium ion, and imidazolium ion.

[0060] In some embodiments, the divalent cation includes Pb 2+ , Sn 2+ , Be 2+ , Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Zn 2+ , Ge 2+ , Fe 2+ , Co 2+ and Cu 2+ among one or more.

[0061] In some embodiments, the organic diamine cation includes one or more of ethylenediamine divalent cation, butanediamine divalent cation, benzenedimethyldiamine divalent cation, and piperazine divalent cation.

[0062] In some embodiments, referring to Figure 1 , the perovskite solar cell further includes a second charge transport layer 13 disposed on the other side of the perovskite light-absorbing layer 11, and the second charge transport layer 13 includes an electron transport material.

[0063] The second charge transport layer includes an electron transport material, which is beneficial to the transport and extraction of electrons, thereby facilitating the formation of electron and hole transport and recombination between the first charge transport layer, the perovskite light-absorbing layer, and the second charge transport layer, and facilitating the perovskite solar cell to have a high photoelectric conversion efficiency.

[0064] In some embodiments, the electron transport material includes one or more of fullerene C60, fullerene C70, PC 61 BM ([6,6]-phenyl-C61-butyric acid methyl ester), [6,6]-phenyl C71 butyric acid methyl ester (PC 71 BM).

[0065] In some embodiments, referring to Figure 1 , the perovskite solar cell further includes a first electrode 12 and a second electrode 16; the first electrode 12 is disposed on the side of the first charge transport layer 10 away from the perovskite light-absorbing layer 11, and the second electrode 16 is disposed on the side of the second charge transport layer 13 away from the perovskite light-absorbing layer 11.

[0066] In some embodiments, one of the first electrode and the second electrode is a transparent electrode for light incident. Among the first electrode and the second electrode, one is used to collect electron carriers, and the other is used to collect hole carriers.

[0067] In some embodiments, the first electrode is a transparent electrode; optionally, the first electrode includes ITO glass and the second electrode includes a metal electrode. At this time, the perovskite solar cell has a reverse structure, and the perovskite light-absorbing layer is prepared on the hole transport material. Since the hole transport material has good tolerance and wettability to the perovskite precursor solution, after the perovskite precursor solution is coated on the hole transport material, the pinhole morphology defects in the formed perovskite light-absorbing layer can be reduced, the interface electron trap density can be lowered, and the crystallization film-forming property and stability of the perovskite light-absorbing layer can be improved. Thus, in the perovskite solar cell with a reverse structure, the hole transport material has a better improvement effect on the perovskite light-absorbing layer.

[0068] In a second aspect, the present application provides a tandem solar cell, including a light-absorbing layer, a first carrier transport layer, and a second carrier transport layer, wherein the light-absorbing layer is disposed between the first carrier transport layer and the second carrier transport layer;

[0069] The light-absorbing layer includes a first light-absorbing layer, a composite layer, and a second light-absorbing layer which are sequentially stacked, and at least one of the first light-absorbing layer and the second light-absorbing layer is a perovskite layer;

[0070] One of the first carrier transport layer and the second carrier transport layer contains a hole transport material, and the other contains an electron transport material. The hole transport material includes a compound shown in Formula I as follows:

[0071] Formula I

[0072] In Formula I, A1 and A2 are each independently selected from one of an O atom and an S atom.

[0073] The hole transport material with the structure shown in Formula I provided by the present application combines a carbazole-based phosphoric acid with a phenylfluoreneamine group (i.e., N-methoxyphenyl-dimethylfluorenamine group). After the two are combined and interact with each other, it can not only endow the hole transport material itself with good film-forming property, but also has good tolerance and wettability to the perovskite precursor solution, can reduce the pinhole morphology defects in the perovskite light-absorbing layer formed adjacent to the hole transport material, lower the interface electron trap density, and improve the crystallization film-forming property and stability of the perovskite light-absorbing layer.

[0074] Meanwhile, since the hole transporting material itself has good film-forming properties, and the interaction between the carbazole-based phosphoric acid and the phenylfluoreneamine group enables the hole transporting material to have a relatively deep HOMO energy level and a high carrier mobility that match the perovskite light-absorbing layer, the hole transporting material does not require the addition of a dopant during use, has good repeatability, and has good application prospects. Overall, the hole transporting material with the structure shown in Formula I is conducive to improving the stability and photoelectric conversion efficiency of the tandem solar cell.

[0075] In some embodiments, the first light-absorbing layer is adjacent to the first carrier transporting layer. The first light-absorbing layer is a perovskite layer, and the first carrier transporting layer contains the hole transporting material. Such an arrangement is conducive to effectively exerting the improvement effect of the hole transporting material on the perovskite layer, and improving the stability and photoelectric conversion efficiency of the tandem solar cell.

[0076] In a third aspect, the present application provides a photovoltaic module, including at least one of the perovskite solar cell described in the first aspect of the present application and the tandem solar cell described in the second aspect of the present application.

[0077] In a fourth aspect, the present application provides a preparation method of a hole transporting material, which can be used to prepare the hole transporting material described above in the present application, and may include the following steps:

[0078] Carry out a first substitution reaction on the compound of Formula II and the compound of Formula III to generate the compound of Formula IV;

[0079] Carry out a hydrolysis reaction on the compound of Formula IV to generate the compound shown in Formula I below, forming the hole transporting material;

[0080] Formula II, Formula III,

[0081] Formula IV,

[0082] Formula I,

[0083] In Formula II, X1 and X2 each independently selected from halogen atoms, and may be selected as Br atoms;

[0084] In Formula III, A is selected from an O atom or an S atom;

[0085] In Formula IV and Formula I, A1 and A2 each independently selected from an O atom or an S atom.

[0086] The above preparation method has simple synthesis steps, low cost, good repeatability, and is conducive to realizing the large-scale preparation of perovskite solar cells.

[0087] In some embodiments, the molar ratio of the compound of Formula II to the compound of Formula III is 1:(2.2 - 3).

[0088] In some embodiments, the molar ratio of the compound of Formula IV to the silane containing a silicon - halogen bond is 1:(8 - 15).

[0089] In some embodiments, the silane containing a silicon - halogen bond includes one or more of trimethylbromosilane, triethylchlorosilane, trimethylchlorosilane, and triethylchlorosilane, and may be trimethylbromosilane optionally.

[0090] In some embodiments, the preparation method of the compound of Formula II may include the following steps:

[0091] Perform a first halogen substitution reaction on the compound of Formula V to generate the compound of Formula VI;

[0092] Perform a third substitution reaction on the compound of Formula VI with a phosphite compound to generate the compound of Formula II;

[0093] Formula V, Formula VI;

[0094] In Formula VI, X3 is selected from halogen atoms, and may be a Br atom optionally.

[0095] In some embodiments, the phosphite compound includes one or more of triethyl phosphite, diethyl phosphite, and trimethyl phosphite, and may be triethyl phosphite optionally.

[0096] In some embodiments, the molar ratio of the compound of Formula VI to the phosphite compound is 1:(25 - 50).

[0097] In some embodiments, the preparation method of the compound of Formula III may include the following steps:

[0098] Perform a second halogen substitution reaction on the compound of Formula VII and the compound of Formula VIII to generate the compound of Formula IX;

[0099] Perform a fourth substitution reaction on the compound of Formula IX with tert - butylpinacol borate to generate the compound of Formula III.

[0100] Formula VII, Formula VIII, Formula IX;

[0101] In Formula VIII, X4 is selected from halogen atoms, and may be a Br atom optionally.

[0102] In some embodiments, the molar ratio of the compound of Formula VII to the compound of Formula VIII is 1:(0.7 - 1).

[0103] In some embodiments, the molar ratio of the compound of formula IX to pinacol borate tert-butyl ester is 1:(1.2~1.5).

[0104] As a non-limiting example, the preparation method of the hole transporting material is as follows:

[0105] Reaction step i: The compound of formula VII, the compound of formula VIII, sodium tert-butoxide, tris(dibenzylideneacetone)dipalladium(0), and 2-(dicyclohexylphosphino)-2′,4′,6′-triisopropylbiphenyl are mixed and dissolved in toluene, and heated for reaction under a nitrogen atmosphere. After the reaction is completed, the compound of formula IX is obtained by separation and purification. The molar ratio of the compound of formula VII, the compound of formula VIII, sodium tert-butoxide, tris(dibenzylideneacetone)dipalladium(0), and 2-(dicyclohexylphosphino)-2′,4′,6′-triisopropylbiphenyl is 1:(0.7~1):(1~2):(0.01~0.05):(0.02~0.1).

[0106] Reaction step ii: Under the protection of an inert gas, the compound of formula IX is added to a 500 mL three-necked flask, and then dry THF (tetrahydrofuran) is added. The mixture is cooled to -78 °C and stirred for 10~20 min, and then n-butyllithium is slowly added dropwise. The reaction is carried out at -78 °C for 1 hour, then pinacol borate tert-butyl ester is added, and the reaction is continued at -78 °C for 1 hour. Finally, the reaction mixture is transferred to room temperature and reacted for 10~16 hours. The mixture is extracted with DCM (dichloromethane), the organic phase is dried over anhydrous Mg2SO4, filtered, and distilled under reduced pressure. The crude product is separated and purified by silica gel column chromatography and dried in vacuo to obtain the compound of formula III. The molar ratio of the compound of formula IX, n-butyllithium, and pinacol borate tert-butyl ester is 1:(1.1~1.3):(1.2~1.5).

[0107] Reaction step iii: Under the protection of an inert gas, the compound of formula V, tetrabutylammonium bromide, and KOH are dissolved in 1,2-dibromobutane for a substitution reaction. The reaction temperature is 65~70 °C, and the reaction time is 12~24 h. After the reaction is completed, the reaction is quenched with water, the mixture is extracted with DCM, the organic phase is dried over anhydrous Mg2SO4, filtered, and distilled under reduced pressure. The crude product is separated and purified by silica gel column chromatography and dried in vacuo to obtain the compound of formula VI. The molar ratio of the compound of formula V, tetrabutylammonium bromide, KOH, and 1,2-dibromobutane is 1:(0.1~0.2):(5~10):(50~200).

[0108] Reaction step iv: Under the protection of an inert gas, the compound of formula VI and triethyl phosphite are reacted. The reaction temperature is 140~150 °C, and the reaction time is 12~16 h. After cooling to room temperature, the mixture is extracted with DCM, the organic phase is dried over anhydrous Mg2SO4, filtered, and distilled under reduced pressure to obtain the compound of formula II.

[0109] Reaction step ⅴ: Under the protection of an inert gas, Compound Ⅱ, Compound Ⅲ, tetrakis(triphenylphosphine)palladium, and potassium carbonate are placed in a solvent, which is toluene, ethanol, and water (the volume ratio can be 2:1:1). The reaction temperature is 80 - 90 °C, and the reaction time is 6 - 12 h. After cooling to room temperature, the mixture is extracted with DCM, the organic phase is dried over anhydrous Mg2SO4, filtered, and distilled under reduced pressure. The crude product is separated and purified by silica gel column chromatography and dried in vacuo to obtain Compound Ⅳ. The molar ratio of Compound Ⅱ, Compound Ⅲ, tetrakis(triphenylphosphine)palladium, and potassium carbonate is 1:(2.2 - 3):(0.02 - 0.1):(5 - 8).

[0110] Reaction step ⅵ: Under the protection of an inert gas, Compound Ⅳ is dissolved in 1,4 - dioxane at 25 °C, trimethylsilyl bromide is added dropwise, and then stirred overnight. The solvent is removed by a rotary evaporator to obtain a solid powder. The solid powder is dissolved in methanol at room temperature, and then deionized water is added dropwise until the mixture becomes opaque, and then stirred for 10 - 16 hours. The crude product is collected by filtration and washed with deionized water. The crude product is dissolved in THF and reprecipitated in acetone, and the final Compound Ⅰ is obtained by filtration. The molar ratio of Compound Ⅳ and trimethylsilyl bromide is 1:(8 - 15).

[0111] Examples

[0112] The following are specific examples. The following examples more specifically describe the content disclosed in the present application. These examples are only for illustrative purposes, because various modifications and changes within the scope of the present application are obvious to those skilled in the art. Unless otherwise stated, all parts, percentages, and ratios reported in the following examples are based on weight, and all reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further treatment, and all instruments used in the examples are commercially available.

[0113] Example 1

[0114] (1) Preparation of hole - transporting material

[0115] Synthesis of Compound 3: Compound 1 (1.61 g, 5.11 mmol), Compound 2 (1.02 g, 4.26 mmol), sodium tert-butoxide (0.61 g, 6.35 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.077 mg, 0.085 mmol), and 2-(dicyclohexylphosphino)-2′,4′,6′-triisopropylbiphenyl (0.081 g, 0.169 mmol) were mixed and dissolved in toluene (30 mL), then charged into a two-necked round-bottom flask. Under a nitrogen atmosphere, the mixture was heated to 110 °C and stirred for 8 h. After the reaction was completed, it was cooled to room temperature, extracted with ethyl acetate, and the organic layer was washed with brine (100 mL × 3), and then dried over anhydrous sodium sulfate. Then the solvent was removed under reduced pressure, and purified by silica gel column chromatography (DCM / PE with a volume ratio of 1:4) to obtain yellow solid Compound 3 (1.48 g, 73.2%).

[0116]

[0117] Synthesis of Compound 4: Weighed Compound 3 (4.74 g, 10 mmol) was added to a 500 mL three-necked flask, and then 30 mL of dry THF was added. Under N2 conditions, it was cooled to -78 °C and stirred for 10 min, and then n-butyllithium 3.75 mL (1.00 equivalent (i.e., the molar ratio to the reactant is 1:1), stored in n-hexane at 1.6 mol / L) was slowly added dropwise. The reaction was carried out at -78 °C for 1 h, then tert-butylpinacol borate (2.75 mL, 15 mmol) was added, and the reaction was continued at -78 °C for 1 h, and finally transferred to room temperature and reacted for 12 h; 50 mL of deionized water was used to quench the reaction, and saturated NaCl solution and DCM were used for extraction. The organic phase was dried over anhydrous Mg2SO4, filtered, and finally purified by column chromatography (PE:DCM = 15:1) to obtain 4.8 g of Compound 4 with a yield of 80%.

[0118]

[0119] Synthesis of Compound 6: Compound 5 (0.97 g, 3 mmol) and tetrabutylammonium bromide (0.1 g, 0.3 mmol) were dissolved in 1,2-dibromobutane (20 mL) in a 100 mL two-necked flask, and then 50% aqueous potassium hydroxide solution (5 mL) was added dropwise. The mixture was heated to 65 °C and then stirred overnight. The reaction was quenched with water, extracted with dichloromethane, the organic layer was combined and dried over anhydrous magnesium sulfate, and then the organic solvent was removed with a rotary evaporator to obtain the crude product. Further purification was carried out by silica gel column chromatography using petroleum ether / dichloromethane = 10 / 1 as the eluent to obtain 1.1 g of Compound 6 with a yield of 88%.

[0120]

[0121] Synthesis of Compound 7: Add Compound 6 (1.38 g, 3.0 mmol) and triethyl phosphite (10 mL) into a 100 mL two-necked flask, then heat the mixture to 160 °C and stir overnight under a nitrogen atmosphere. Extract with dichloromethane, combine and dry the organic layer with anhydrous magnesium sulfate, and then remove the organic solvent with a rotary evaporator to obtain the crude product Compound 7 (1.08 g, 2.1 mmol) with a yield of 70%.

[0122]

[0123] Synthesis of Compound 8: Add Compound 7 (0.52 g, 1 mmol), Compound 4 (1.32 g, 2.2 mmol), tetrakis(triphenylphosphine)palladium (57 mg, 0.05 mmol), and potassium carbonate (0.83 g, 6 mmol) into a 100 mL two-necked flask. The solvent is toluene, ethanol, and water (in a ratio of 2:1:1), and react at 85 °C for 6 hours. Cool to room temperature, extract the mixture with DCM, dry the organic phase with anhydrous Mg2SO4, filter, and distill under reduced pressure. Finally, purify by column chromatography (PE:DCM = 4:1) to obtain Compound 8 (0.85 g, 0.65 mmol) with a yield of 65%.

[0124]

[0125] Synthesis of Cz-1: Add Compound 8 (2.6 g, 2 mmol) into 10 mL of anhydrous 1,4-dioxane at room temperature in a 100 mL two-necked flask, dropwise add trimethylsilyl bromide (3.06 g, 20 mmol), and then stir overnight. Remove 1,4-dioxane with a rotary evaporator to obtain a solid powder. Dissolve the solid powder in methanol (10 mL) at room temperature, and then dropwise add deionized water until the mixture becomes opaque, and stir for another 12 hours. Collect the crude product by filtration and wash with deionized water. Dissolve the crude product in THF (5 mL) and reprecipitate in acetone (20 mL), and filter to obtain the final product Cz-1 (1.74 g, yield 70%). The 1H NMR spectrum of the product Cz-1 is as Figure 2 shown.

[0126]

[0127] (2) Preparation of perovskite solar cells

[0128] (2.1) Cleaning: Ultrasonically clean the ITO glass substrate with deionized water, acetone, and ethanol in sequence for 15 - 20 minutes, then use an N2 gas gun to blow dry the residual solvent on the ITO surface, perform oxygen plasma treatment for 10 minutes, and then transfer the ITO glass substrate to a nitrogen glove box.

[0129] (2.2) Preparation of hole transport layer: Weigh 10 mg of the hole transport material Cz-1 prepared in step (1) and completely dissolve it in 1 mL of chlorobenzene solution. Take an appropriate amount of the solution and evenly drop it onto the ITO glass substrate, spin-coat it at 4000 rpm for 20 seconds, and then anneal it at 100 °C for 10 minutes to obtain the ITO / hole transport layer substrate.

[0130] (2.3) Preparation of perovskite layer: Cool the obtained ITO / hole transport layer substrate to room temperature, preheat it at 130 °C for 4 minutes, take 50 μL of perovskite solution and spread it evenly on the ITO / hole transport layer substrate, spin-coat it at 4000 rpm for 20 seconds, and then anneal it at 100 °C for 10 minutes to prepare the perovskite layer. The preparation of the perovskite solution is as follows: Mix 3-bromo-benzylammonium iodide, methylammonium chloride, and lead iodide in a molar ratio of 2.2:3.5:4 in a mixed solution of DMF and DMSO, with the volume ratio of DMF to DMSO being 4:1, to obtain the ITO / hole transport layer / perovskite substrate.

[0131] (2.4) Preparation of electron transport layer: Cool the obtained ITO / hole transport layer / perovskite substrate to room temperature, configure PC 61 BM into a 15 mg / mL solution, and then take 40 μL of the PC 61 BM solution and spread it evenly on the ITO / hole transport layer / perovskite substrate, spin-coat it at 1000 rpm for 40 seconds, and anneal it at 70 °C for 10 minutes.

[0132] (2.5) Preparation of electrode: Place the above substrate in a vacuum evaporation chamber, and deposit Cr (6 nm) and Au (80 nm) on the PC 61 BM layer respectively to obtain a reverse-type quasi-two-dimensional perovskite solar cell.

[0133] Example 2

[0134] Synthesis of compound 10: Mix compound 9 (1.69 g, 5.11 mmol), compound 2 (1.02 g, 4.26 mmol), sodium tert-butoxide (0.61 g, 6.35 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.077 mg, 0.085 mmol), and 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (0.081 g, 0.169 mmol) and dissolve them in toluene (30 mL). Put them into a two-necked round-bottom flask, heat to 110 °C under a nitrogen atmosphere, stir and react for 8 h. After the reaction is completed, cool to room temperature, extract with ethyl acetate, wash the organic layer with brine (100 mL × 3), and then dry it with anhydrous sodium sulfate. Then remove the solvent under reduced pressure and purify it by silica gel column chromatography (DCM / PE with a volume ratio of 1:4) to obtain compound 10 (1.45 g, 71%).

[0135]

[0136] Synthesis of Compound 11: Weigh Compound 10 (4.89 g, 10 mmol) and add it to a 500 mL three-necked flask. Then add 30 mL of dry THF. Cool the mixture to -78 °C under N2 and stir for 10 min. Then slowly add n-butyllithium (3.75 mL, 1.00 equiv, 1.6 M in n-hexane) dropwise. React at -78 °C for 1 hour. After that, add tert-butyl pinacol borate (2.75 mL, 15 mmol) and continue to react at -78 °C for 1 hour. Finally, transfer the reaction mixture to room temperature and react for 12 hours. Quench the reaction with 50 mL of deionized water, extract with saturated NaCl solution and DCM. Dry the organic phase over anhydrous Mg2SO4, filter, and finally purify by column chromatography (PE:DCM = 15:1) to obtain 5.0 g of Compound 11 with a yield of 82%.

[0137]

[0138] Synthesis of Compound 6: Add Compound 5 (0.97 g, 3 mmol) to a 100 mL two-necked flask. Dissolve tetrabutylammonium bromide (0.1 g, 0.3 mmol) in 1,2-dibromobutane (20 mL), and then add 50% aqueous potassium hydroxide solution (5 mL) dropwise. Heat the mixture to 65 °C and stir overnight. Quench the reaction with water, extract with dichloromethane, dry the combined organic layers over anhydrous magnesium sulfate, and then remove the organic solvent using a rotary evaporator to obtain the crude product. Further purify by silica gel column chromatography using a eluent of petroleum ether / dichloromethane = 10 / 1 to obtain 1.1 g of Compound 6 with a yield of 88%.

[0139]

[0140] Synthesis of Compound 7: Add Compound 6 (1.38 g, 3.0 mmol) and triethyl phosphite (10 mL) to a 100 mL two-necked flask. Then heat the mixture to 160 °C and stir overnight under a nitrogen atmosphere. Extract with dichloromethane, dry the combined organic layers over anhydrous magnesium sulfate, and then remove the organic solvent using a rotary evaporator to obtain the crude product Compound 7 (1.08 g, 2.1 mmol) with a yield of 70%.

[0141]

[0142] Synthesis of Compound 12: In a 100 mL two-necked flask, add Compound 7 (0.52 g, 1 mmol), Compound 11 (1.35 g, 2.2 mmol), tetrakis(triphenylphosphine)palladium (57 mg, 0.05 mmol), and potassium carbonate (0.83 g, 6 mmol). The solvent is toluene, ethanol, and water (in a ratio of 2:1:1). React at 85 °C for 6 hours. Cool to room temperature, extract the mixture with DCM, dry the organic phase with anhydrous Mg2SO4, filter, and distill under reduced pressure. Finally, purify by column chromatography (PE:DCM = 4:1) to obtain Compound 12 (0.8 g, 0.6 mmol) with a yield of 60%.

[0143]

[0144] Synthesis of Cz-2: Add Compound 12 (2.6 g, 2 mmol) to 100 mL of anhydrous 1,4-dioxane at room temperature in a two-necked flask. Dropwise add trimethylsilyl bromide (3.06 g, 20 mmol), and then stir overnight. Remove 1,4-dioxane using a rotary evaporator to obtain a solid powder. Dissolve the solid powder in methanol (10 mL) at room temperature, and then dropwise add deionized water until the mixture becomes opaque, and stir for another 12 hours. Collect the crude product by filtration and wash it with deionized water. Dissolve the crude product in THF (5 mL) and reprecipitate it in acetone (20 mL). Filter to obtain the final product Cz-2 (1.79 g, yield 70%). The 1H NMR spectrum of the product Cz-2 is as Figure 3 shown.

[0145]

[0146] (2) Preparation of Perovskite Solar Cells

[0147] (2.1) Cleaning: Ultrasonically clean the ITO glass substrate with deionized water, acetone, and ethanol in sequence for 15 - 20 minutes. Then use an N2 gas gun to blow dry the residual solvent on the ITO surface, followed by 10 minutes of oxygen plasma treatment. Subsequently, transfer the ITO glass substrate to a nitrogen glove box.

[0148] (2.2) Preparation of the Hole Transport Layer: Weigh 10 mg of the hole transport material Cz-2 prepared in step (1) and dissolve it completely in 1 mL of chlorobenzene solution. Take an appropriate amount of the solution and uniformly drop it onto the ITO glass substrate, spin-coat at 4000 rpm for 20 seconds, and then anneal at 100 °C for 10 minutes to obtain the ITO / hole transport layer substrate.

[0149] (2.3) Preparation of perovskite layer: Cool the obtained ITO / hole transport layer substrate to room temperature, preheat it at 130 °C for 4 minutes, take 50 μL of perovskite solution and spread it evenly on the ITO / hole transport layer substrate, spin-coat it at 4000 rpm for 20 seconds, and then anneal it at 100 °C for 10 minutes to prepare the perovskite layer. The preparation of the perovskite solution is as follows: Mix 3-bromo-benzylammonium iodide, methylammonium chloride, and lead iodide in a molar ratio of 2.2:3.5:4 in a mixed solution of DMF and DMSO, with the volume ratio of DMF to DMSO being 4:1, to obtain the ITO / hole transport layer / perovskite substrate.

[0150] (2.4)Preparation of electron transport layer: Cool the obtained ITO / hole transport layer / perovskite substrate to room temperature, and prepare a solution of PC 61 BM with a concentration of 15 mg / mL. Then take 40 μL of the PC 61 BM solution and spread it evenly on the ITO / hole transport layer / perovskite substrate, spin-coat it at 1000 rpm for 40 seconds, and anneal it at 70 °C for 10 minutes.

[0151] (2.5)Preparation of electrodes: Place the above-mentioned substrate in a vacuum evaporation chamber, and deposit Cr (6 nm) and Au (80 nm) on the PC 61 BM layer respectively, then the inverted quasi-two-dimensional perovskite solar cell can be prepared.

[0152] Comparative Example 1

[0153] The preparation process of the perovskite solar cell is similar to that of Example 1, and the main difference is that in step (2.2), the N-methoxyphenyl-dimethylfluorenamine group in Cz-1 is omitted, and an equal mass of carbazolyl phosphoric acid (PACZ) is used to replace the hole transport material Cz-1.

[0154] Comparative Example 2

[0155] The preparation process of the perovskite solar cell is similar to that of Example 1, and the main difference is that in step (2.2), the carbazolyl phosphoric acid main body in Cz-1 is omitted (retaining the phenylfluorenamine group), and an equal mass of Spiro-OMeTAD is used to replace the hole transport material Cz-1.

[0156] Perform relevant performance tests on the perovskite solar cells prepared in Examples 1-2 and Comparative Examples 1-2, and the test results are shown in Tables 1 and 2 below.

[0157] Among them, the test conditions or test standards for each performance test item are as follows:

[0158] (1)Test of decomposition temperature of hole transport material

[0159] Thermal analysis characterization was carried out using a differential scanning calorimeter. N2 was selected as the program protection gas. During the test, the purge flow rates were set to 20 cm 3 / min, the starting temperature was set to 25 °C, the heating rate was 10 °C / min, heated to 300 °C, and then cooled to room temperature at a cooling rate of 20 °C / min, and two rounds of heating and cooling procedures were carried out. The thermal stability performance of the target product was analyzed by studying the test curve.

[0160] (2)Measurement of the carrier mobility of the hole transport material

[0161] The space charge limited current method was used to measure the hole mobility. A single hole device of ITO / PEDOT:PSS / HTMs to be tested / MoO3 / Ag was prepared, and the film thickness of each layer was determined by a step profiler. The J-V characteristic curve of the device was obtained by a Keithley 2450 Source-Measure instrument under dark conditions. Nonlinear fitting analysis was performed on the curve to obtain the carrier mobility of the sample.

[0162] (3)Measurement of the HOMO energy level of the hole transport material

[0163] 5 mg of the compound was dissolved in a dichloromethane solution of 0.1 M tetrabutylammonium hexafluorophosphate (Bu4NPF6), and ferrocene was used as an external standard for calibration. A cyclic voltammogram was obtained on an electrochemical workstation at a purge rate of 0.01 V / s. The redox potential of the curve was analyzed, and the HOMO of the material was calculated according to the formula

[0164] (4)Measurement of the roughness of the perovskite layer

[0165] The sample to be tested was prepared on an ITO substrate, and the surface topography of the film was photographed using an atomic force microscope.

[0166] (5)Measurement of the photoelectric conversion efficiency of the perovskite solar cell

[0167] Under normal temperature and pressure, under the irradiation of standard simulated sunlight (AM 1.5G, 100 milliwatts per square centimeter (mW / cm 2 2)), the performance of the battery was tested to obtain the I-V curve (volt-ampere characteristic curve). According to the I-V curve and the data feedback from the test equipment (four-channel digital source meter, Keithley 2440), the short-circuit current density Jsc (unit: milliampere per square centimeter (mA / cm2)), open-circuit voltage Voc (unit: volt (V)), maximum light output current Jmpp (unit: milliampere (mA)), maximum light output voltage Vmpp (unit: V), and series resistance (unit: Ω) can be obtained.

[0168] The fill factor FF of the battery can be calculated by the formula FF = Jsc × Voc / (Jmpp × Vmpp), with the unit of %. The photoelectric conversion efficiency PCE of the battery can be calculated by the formula PCE = Jsc × Voc × FF / Pw, with the unit of %; Pw represents the input power, with the unit of milliwatt (mW).

[0169] "Normal temperature and pressure" refers to normal pressure: the pressure is one atmosphere at a temperature of 25°C; normal temperature refers to 20°C to 30°C, and further, it can be 25°C.

[0170] (6) Stability test of perovskite solar cells

[0171] After storing the perovskite solar cell in an inert environment for 1200 hours, its photoelectric conversion efficiency is tested to characterize its stability.

[0172] Table 1

[0173]

[0174] Table 2

[0175]

[0176] In Table 2, it can be seen from the comparison between Examples 1-2 and Comparative Examples 1-2 that compared with the traditional hole transport materials in Comparative Examples 1-2, the hole transport material formed by combining carbazole-based phosphoric acid and phenylfluorenamine groups in this application can improve the photoelectric conversion efficiency and stability of the battery.

[0177] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0178] The above-described embodiments only represent several implementation manners of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several deformations and improvements can still be made, and these all belong to the protection scope of this application. Therefore, the protection scope of the patent of this application should be subject to the appended claims.

Claims

1. A perovskite solar cell, characterized in that, The invention comprises a perovskite light absorbing layer and a first charge transport layer disposed on one side of the perovskite light absorbing layer, wherein the first charge transport layer comprises a hole transport material, and the hole transport material comprises a compound shown in the following formula I: Formula Ⅰ In formula I, A1 and A2 are each independently selected from one of an O atom and a S atom.

2. The perovskite solar cell according to claim 1, characterized in that, The hole transport material comprises at least one of the following formula I-1 and formula I-2: Formula I-1, Formula I-2.

3. The perovskite solar cell according to claim 1 or 2, characterized in that, The roughness of the surface of the perovskite light absorbing layer adjacent to the first charge transport layer is less than 20 nm, and can be selected to be 10 nm to 15 nm.

4. The perovskite solar cell according to any one of claims 1 to 3, characterized in that, The hole transport material satisfies one or more of the following conditions: (1) The decomposition temperature of the hole transport material is 225°C to 235°C; (2) The carrier mobility of the hole transport material is 2.35×10 -4 cm 2 ·V -1 ·s -1 ~3.30×10 -4 cm 2 ·V -1 ·s -1 ; (3) The HOMO energy level of the hole transport material is -5.25 eV to -5.35 eV.

5. The perovskite solar cell according to any one of claims 1 to 4, characterized in that, The perovskite light-absorbing layer comprises a quasi-two-dimensional perovskite material, and the quasi-two-dimensional perovskite material includes (RNH3)2A1’ n1-1 B1’ n1 X1 3n1+1 , A’A2’ n2- 1B2’ n2 X2 3n2+1 and (GA)A3 n3 M n3 X3 3n3+1 or one or more of them; wherein R comprises one or more of a substituted or unsubstituted alkyl group having a carbon number greater than or equal to 2, a substituted or unsubstituted aryl group, A1', A2' and A3 each independently comprise one or more of monovalent cations, A' is an organic diamine cation, B1', B2' and M each independently comprise one or more of divalent cations, X1, X2 and X3 each independently comprise one or more of halogen ions, GA is a guanidine ion, and n1, n2 and n3 each independently are greater than 1; Optionally, the monovalent cation includes one or more of methylamine ion, ethylamine ion, propylamine ion, butylamine ion, pentylamine ion, hexylamine ion, formamidinium ion and imidazolyl ion; Optionally, the divalent cation includes Pb 2+ , Sn 2+ , Be 2+ , Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Zn 2+ , Ge 2+ , Fe 2+ , Co 2+ and Cu 2+ ; one or more of these Optionally, the organic diamine cation includes one or more of ethylenediamine divalent cation, butanediamine divalent cation, xylylenediamine divalent cation and piperazine divalent cation.

6. The perovskite solar cell according to any one of claims 1 to 5, characterized in that, The perovskite solar cell further includes a second charge transport layer disposed on the other side of the perovskite light absorbing layer, wherein the second charge transport layer includes an electron transport material.

7. The perovskite solar cell according to claim 6, wherein The perovskite solar cell further comprises a first electrode and a second electrode; the first electrode is arranged on a side of the first charge transport layer away from the perovskite light absorption layer, and the second electrode is arranged on a side of the second charge transport layer away from the perovskite light absorption layer; Optionally, the first electrode is a transparent electrode.

8. A stacked solar cell, characterized in that, It includes a light absorbing layer, a first carrier transport layer and a second carrier transport layer, wherein the light absorbing layer is arranged between the first carrier transport layer and the second carrier transport layer; The light absorbing layer comprises a first light absorbing layer, a composite layer, and a second light absorbing layer which are sequentially stacked, and at least one of the first light absorbing layer and the second light absorbing layer is a perovskite layer; One of the first carrier transport layer and the second carrier transport layer comprises a hole transport material, and the hole transport material comprises a compound represented by the following formula I: Formula Ⅰ In formula I, A1 and A2 are each independently selected from one of an O atom and a S atom.

9. The stacked solar cell according to claim 8, wherein, The first light absorption layer is adjacent to the first carrier transport layer, the first light absorption layer is a perovskite layer, and the first carrier transport layer contains the hole transport material.

10. A photovoltaic module, characterized in that, including at least one of the perovskite solar cell according to any one of claims 1 to 7 and the tandem solar cell according to any one of claims 8 to 9.

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