Fullerene derivative, method for preparing same, and perovskite solar cell

Abstract

The application provides a fullerene derivative, a preparation method thereof and a perovskite solar cell. The fullerene derivative has a structure shown in general formula (I) or (II). The fullerene derivative provided in the application contains a phosphoric acid group. When the fullerene derivative is applied to a perovskite solar cell, H in the phosphoric acid group can form a hydrogen bond with I in a perovskite active layer, and O can form a coordination bond with Pb, so that the perovskite active layer can be passivated, and the stability thereof is improved. The fullerene derivative can also form an intermolecular force between the fullerene derivative and iodine atoms in the perovskite active layer, so that the longitudinal growth of perovskite active material grains can be adjusted, the crystal plane defects are reduced, and the stability of the perovskite active layer is improved. Compared with other substituents, the use of the R has advantages of improving the solubility of the fullerene derivative, improving the passivation performance of the fullerene derivative, and improving the performance of the perovskite solar cell.

Description

Technical Field

[0001] This invention relates to the field of solar cell technology, and more specifically, to a fullerene derivative, its preparation method, and a perovskite solar cell. Background Technology

[0002] Fullerene-based n-type charge-collecting materials have become a solution for high-performance perovskite solar cells. Introducing fullerenes and their derivatives as additives into the perovskite layer can promote charge transport and effectively passivate defects in the perovskite film itself, suppressing phase separation and thus further improving device performance.

[0003] Existing literature (Palladium-Catalyzed Heteroannulation of

[60] Fullerene with Anilides via CH Bond Activation. Org. Lett. 2009, 11, 4334-4337.) discloses a synthetic method for fullerene indoline derivatives having the following structures: However, there are no reports proving whether fullerene indoline derivatives can be applied to perovskite solar devices.

[0004] Therefore, researching and developing a novel fullerene derivative is of great significance for improving the energy conversion efficiency and stability of perovskite solar cells. Summary of the Invention

[0005] The main objective of this invention is to provide a fullerene derivative, its preparation method, and a perovskite solar cell, in order to solve the problem that the passivation effect of fullerene derivatives on the perovskite active layer in the prior art needs to be improved, resulting in poor energy conversion efficiency and stability of perovskite solar cells.

[0006] To achieve the above objectives, the present invention provides a fullerene derivative having the structure shown in general formula (I) or (II):

[0007]

[0008] Where n takes the value 0 or 1;

[0009] When n is 1, Ar is selected from any one of the general formulas (III) to (VII):

[0010]

[0011] When n is 0, Ar is selected from C6 to C6 of a nitrogen-containing five-membered heterocycle with m R-substituted carbon-carbon bonds. 14The arylene group, m is 1 or 2; R is selected from H, F, Br, C1-C1. 12 Alkyl groups, C1-C 12 alkoxy or C2~C 11 The ester group; q is any integer from 2 to 6; x is 2 or 3.

[0012] To achieve the above objectives, another aspect of the present invention provides a method for preparing a fullerene derivative, the method comprising: S1, under the catalysis of a catalyst, reacting a fullerene with raw material A or raw material B, a first basic compound, and optional additives in a first solvent to obtain a first intermediate; the fullerene is C 60 Or C 70 The first intermediate has the structure shown in general formula (VIII) or (IX):

[0013]

[0014] Raw material A has the structure shown in general formula (X):

[0015]

[0016] Raw material B has the structure shown in general formula (XI):

[0017]

[0018] S2, in the presence of a second basic compound, the first intermediate undergoes a second reaction with a 1,q-dibromosubstituted alkane in a second solvent to give a second intermediate; the second intermediate has the structure shown in general formula (XII) or (XIII):

[0019]

[0020] S3, the second intermediate undergoes a third reaction with triethyl phosphite in a third solvent to give a third intermediate; the third intermediate has the structure shown in general formula (XIV) or (XV):

[0021]

[0022] S4, under an inert atmosphere, the third intermediate undergoes a fourth reaction with trimethylbromosilane in a fourth solvent, followed by separation and purification to obtain a fullerene derivative; the fullerene derivative has the structure shown in general formula (I) or (II):

[0023]

[0024] Ar, n, q, and x have the same meaning as those in the preceding text.

[0025] Another aspect of the present invention provides a perovskite solar cell, which includes a transparent conductive substrate, a first carrier transport layer, a perovskite active layer doped with a fullerene derivative, a second carrier transport layer, and a cathode buffer layer stacked sequentially; the perovskite solar cell also includes a metal electrode layer, which includes a plurality of metal electrodes, wherein a portion of the metal electrodes are disposed on the side surface of the cathode buffer layer away from the first carrier transport layer, and a portion of the metal electrodes are disposed on the conductive surface of the transparent conductive substrate; the fullerene derivative includes one or more of the fullerene derivatives provided in this application, or one or more of the fullerene derivatives prepared by the preparation method of the fullerene derivatives provided in this application.

[0026] By applying the technical solution of this invention, the fullerene derivative provided in this application contains phosphate groups. When applied to perovskite solar cells, the hydrogen atoms (H) in the phosphate groups can form hydrogen bonds with the iodine atoms (I) in the perovskite active layer, while the oxygen atoms (O) can form coordinate bonds with the lead atoms (Pb) in the perovskite active layer, thereby passivating the perovskite active layer and improving its stability. Moreover, since the fullerene derivative is electron-deficient, the iodine atoms have a relatively small binding force on the outer electrons. The fullerene derivative can also form intermolecular forces with the iodine atoms in the perovskite active layer, which can adjust the longitudinal growth of the perovskite active material grains, thereby reducing crystal defects and improving the stability of the perovskite active layer.

[0027] Compared to other substituents, the use of the above-mentioned types of R is beneficial to improving the solubility of fullerene derivatives, improving the passivation performance of fullerene derivatives, thereby reducing the defect state density of perovskite films and thus improving the performance of perovskite solar cells.

[0028] Furthermore, when the aforementioned fullerene derivatives are applied to interface modification layers, the phosphate groups therein can also react with commonly used hole transport materials such as NiO. x The interaction between inorganic metal oxides such as SnO2, an electron transport material, and oxygen vacancies can be filled, thereby reducing interface defects between the hole transport layer and the perovskite active layer or between the electron transport layer and the perovskite active layer, thus improving the stability and energy conversion efficiency of perovskite solar cells. Attached Figure Description

[0029] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0030] Figure 1 A schematic diagram of the structure of the perovskite solar cell fabricated in Device Example 1 is shown;

[0031] Figure 2 A schematic diagram of the structure of the perovskite solar cell fabricated in Device Example 7 is shown.

[0032] The above figures include the following reference numerals:

[0033] 10. Transparent conductive substrate; 20. First carrier transport layer; 30. Perovskite active layer; 40. Second carrier transport layer; 50. Cathode buffer layer; 60. Metal electrode; 70. Interface modification layer. Detailed Implementation

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the embodiments.

[0035] As described in the background section, existing fullerene derivatives suffer from limitations in passivating the perovskite active layer, leading to poor power conversion efficiency and stability in perovskite solar cells. To address these issues, this application provides a fullerene derivative having the structure shown in general formula (I) or (II):

[0036]

[0037] Where n takes the value 0 or 1;

[0038] When n is 1, Ar is selected from any one of the general formulas (III) to (VII):

[0039]

[0040] When n is 0, Ar is selected from C6 to C6 substituted by R. 14 The arylene group, m is 1 or 2; R is selected from H, F, Br, C1-C1. 12 Alkyl groups, C1-C 12 alkoxy or C2~C 11 The ester group; q is any integer from 2 to 6; x is 2 or 3.

[0041] The fullerene derivatives provided in this application contain phosphate groups. When applied to perovskite solar cells, the hydrogen atoms (H) in the phosphate groups can form hydrogen bonds with the iodine atoms (I) in the perovskite active layer 30, while the oxygen atoms (O) can form coordinate bonds with the lead atoms (Pb) in the perovskite active layer 30. This can passivate the perovskite active layer 30 and improve its stability. Moreover, since the fullerene derivatives are electron-deficient, the iodine atoms have a relatively small binding force on the outer electrons. The fullerene derivatives can also form intermolecular forces with the iodine atoms in the perovskite active layer 30, which can adjust the longitudinal growth of the perovskite active material grains, thereby reducing crystal defects and improving the stability of the perovskite active layer 30.

[0042] Compared to other substituents, the use of the above-mentioned types of R is beneficial to improving the solubility of fullerene derivatives, improving the passivation performance of fullerene derivatives, thereby reducing the defect state density of perovskite films and thus improving the performance of perovskite solar cells.

[0043] Furthermore, when the aforementioned fullerene derivatives are applied to the interface modification layer 70, the phosphate groups therein can also react with NiO, a commonly used hole transport material. x The interaction of inorganic metal oxides such as SnO2, an electron transport material, can fill oxygen vacancies, thereby reducing interface defects between the hole transport layer and the perovskite active layer 30 or between the electron transport layer and the perovskite active layer 30, thus improving the stability and energy conversion efficiency of perovskite solar cells.

[0044] In a preferred embodiment, the fullerene derivative is C 60 The derivative is defined as follows: R is H, m is 1, n is 0 or 1, and q is 2, 4, or 6. R, m, n, and q include, but are not limited to, the ranges mentioned above. Limiting them to these ranges is beneficial for further improving the solubility of the fullerene derivative, for further improving the passivation performance of the fullerene derivative, and thus for further reducing the defect state density of the perovskite thin film, thereby for further improving the performance of the perovskite solar cell.

[0045] To further improve the solubility and passivation properties of fullerene derivatives, preferably, when n is 0, Ar includes, but is not limited to, C6-C6 bonds that share carbon-carbon bonds with nitrogen-containing five-membered heterocycles. 12 The arylene group, preferably Ar, includes, but is not limited to, phenylene or naphthylene groups that share carbon-carbon bonds with nitrogen-containing five-membered heterocycles.

[0046] In a preferred embodiment, the fullerene derivative has any one of the following chemical structures:

[0047]

[0048]

[0049] The aforementioned fullerene derivatives are beneficial for further passivating the perovskite active layer 30, thereby further improving its stability.

[0050] A second aspect of this application also provides a method for preparing a fullerene derivative, the method comprising: S1, under the catalysis of a catalyst, reacting a fullerene with raw material A or raw material B, a first basic compound, and optional additives in a first solvent to obtain a first intermediate; the fullerene is C 60 Or C 70 The first intermediate has the structure shown in general formula (VIII) or (IX):

[0051]

[0052] Raw material A has the structure shown in general formula (X):

[0053]

[0054] Raw material B has the structure shown in general formula (XI):

[0055]

[0056] Using fullerene as C 60 For example, when raw material A participates in the first reaction, the synthetic route is as follows, where n is 0:

[0057]

[0058] Using fullerene as C 60 For example, when raw material B participates in the first reaction, the synthetic route is as follows, where n is 1:

[0059]

[0060] S2, in the presence of a second basic compound, the first intermediate undergoes a second reaction with a 1,q-dibromosubstituted alkane in a second solvent to give a second intermediate; the second intermediate has the structure shown in general formula (XII) or (XIII):

[0061]

[0062] Using fullerene as C 60 For example, its synthetic route is as follows:

[0063]

[0064] S3, the second intermediate undergoes a third reaction with triethyl phosphite in a third solvent to give a third intermediate; the third intermediate has the structure shown in general formula (XIV) or (XV):

[0065]

[0066] Using fullerene as C 60 For example, its synthetic route is as follows:

[0067]

[0068] S4, in an inert atmosphere, the third intermediate is reacted with trimethylbromosilane in a fourth solvent to undergo a fourth reaction, followed by separation and purification to obtain the fullerene derivative; the fullerene derivative has the structure shown in general formula (I) or (II):

[0069]

[0070] Using fullerene as C 60 For example, its synthetic route is as follows:

[0071]

[0072] or,

[0073]

[0074] Ar, n, q, and x have the same meaning as those mentioned above.

[0075] Under the catalysis of a catalyst, fullerene undergoes an addition reaction with raw material A or raw material B, a first basic compound, and optional additives in a first solvent, introducing a nitrogen-containing five-membered heterocycle and an Ar group (forming an indoline structure) into the fullerene structure, thereby obtaining a second intermediate. In the presence of a second basic compound, the first intermediate undergoes a second reaction with a 1,q-dibromosubstituted alkane in a second solvent, allowing the N atom in the nitrogen-containing five-membered heterocycle or indoline structure to attach a 1-bromo-n-butyl group, thereby obtaining a second intermediate, which facilitates subsequent esterification. The second intermediate undergoes a third reaction with triethyl phosphite in a third solvent, obtaining a third intermediate. Under an inert atmosphere, the third intermediate undergoes a fourth reaction with trimethylbromosilane in a fourth solvent, thereby introducing a phosphate group. After water quenching, a fullerene derivative is obtained.

[0076] The fullerene derivatives provided in this application contain phosphate groups. When applied to perovskite solar cells, the hydrogen atoms (H) in the phosphate groups can form hydrogen bonds with the iodine atoms (I) in the perovskite active layer 30, while the oxygen atoms (O) can form coordinate bonds with the lead atoms (Pb) in the perovskite active layer 30. This can passivate the perovskite active layer 30 and improve its stability. Moreover, since the fullerene derivatives are electron-deficient, the iodine atoms have a relatively small binding force on the outer electrons. The fullerene derivatives can also form intermolecular forces with the iodine atoms in the perovskite active layer 30, which can adjust the longitudinal growth of the perovskite active material grains, thereby reducing crystal defects and improving the stability of the perovskite active layer 30.

[0077] Compared to other substituents, the use of the above-mentioned types of R is beneficial to improving the solubility of fullerene derivatives, improving the passivation performance of fullerene derivatives, thereby reducing the defect state density of perovskite films and thus improving the performance of perovskite solar cells.

[0078] Furthermore, when the aforementioned fullerene derivatives are applied to the interface modification layer 70, the phosphate groups therein can also react with NiO, a commonly used hole transport material. x The interaction of inorganic metal oxides such as SnO2, an electron transport material, can fill oxygen vacancies, thereby reducing interface defects between the hole transport layer and the perovskite active layer 30 or between the electron transport layer and the perovskite active layer 30, thus improving the stability and energy conversion efficiency of perovskite solar cells.

[0079] Using the preparation method provided in this application, according to the stoichiometric ratio, when the first intermediate has the structure shown in general formula (VIII), if n is 0, the first reaction is a monoaddition process; if n is 1, the amount of fullerene used is at least n times that of raw material B. When the first intermediate has the structure shown in general formula (IX), if x is 2, the first reaction is a diaddition process, and the amount of raw material A used is at least x times that of fullerene; if x is 3, the first reaction is a diaddition process, and the amount of raw material A used is at least x times that of fullerene. By controlling the molar ratio between fullerene and raw material, the product of the first reaction can be controlled to be a monoaddition product, a diaddition product, or a triaddition product. Preferably, the fullerene in the diaddition product and the triaddition product is C0. 60 The fullerene in the monoaddition product is C 60 Or C 70 .

[0080] In a preferred embodiment, when fullerene undergoes a first reaction with raw material A, the molar ratio of fullerene to raw material A is 1:(1-3); when fullerene undergoes a first reaction with raw material B, the molar ratio of fullerene to raw material B is (2-6):1. The molar ratios of fullerene to raw material A or raw material B are not limited to the ranges described above. Limiting these ratios to the ranges improves the utilization rate of raw material A and raw material B and reduces waste.

[0081] In a preferred embodiment, the weight ratio of fullerene to catalyst is 1:(0.05 to 0.3). The weight ratio of fullerene to catalyst includes, but is not limited to, the above range. Limiting it to the above range is beneficial to improving the reaction efficiency of the first reaction and shortening the reaction time.

[0082] In a preferred embodiment, the weight ratio of fullerene to the first basic compound is a molar ratio of 1:(1 to 3). The weight ratio of fullerene to the first basic compound includes, but is not limited to, the above range. Limiting it to the above range is beneficial for maintaining a suitable pH in the first reaction system, which is beneficial for the addition reaction of the nitrogen-containing five-membered heterocycle on the fullerene, thereby improving the yield of the first intermediate.

[0083] In a preferred embodiment, the weight ratio of fullerene to optional additives is a molar ratio of 1:(0.05 to 0.2). The weight ratio of fullerene to optional additives includes, but is not limited to, the above range. Limiting it to the above range is beneficial for reducing by-products and increasing the yield of the first intermediate.

[0084] In a preferred embodiment, the ratio of fullerene to the first solvent is 0.05 mmol:(4–16) mL. The ratio of fullerene to the first solvent includes, but is not limited to, the range described above. Limiting it to this range is beneficial for providing suitable reaction conditions for the reactants, increasing the solubility of the reactants in the first solvent, and facilitating the first reaction.

[0085] To further improve the reaction efficiency of the first reaction, further reduce the amount of by-products generated, and further increase the solubility of the reactants in the first solvent, preferably, the catalyst includes, but is not limited to, palladium acetate; the first basic compound includes, but is not limited to, one or more of the group consisting of triethylenediamine hexahydrate, cesium carbonate, and 4-dimethylaminopyridine; the first solvent includes, but is not limited to, one or more of the group consisting of chlorobenzene, 1,2-dichlorobenzene, and 1,1,2,2-tetrachloroethane; and the additives include, but are not limited to, one or more of the group consisting of 1,2-bis(diphenylphosphine)ethane (DPPE), 1,2-bis(diphenylphosphine)ethane, triphenylphosphine, and lithium chloride.

[0086] In a preferred embodiment, the temperature of the first reaction is 120–140°C, and the time is 20–28 hours. The temperature and time of the first reaction include, but are not limited to, the above ranges. Limiting them to the above ranges is beneficial to increasing the yield of the first intermediate and reducing the amount of by-products generated.

[0087] Using the preparation method provided in this application, according to the stoichiometric ratio, when the first intermediate has the structure shown in general formula (VIII), the amount of 1,q-dibromosubstituted alkane is at least n+1 times the amount of the first intermediate (n is 0 or 1); when the first intermediate has the structure shown in general formula (IX), the amount of 1,q-dibromosubstituted alkane is at least x times the amount of the first intermediate (x is 2 or 3).

[0088] In a preferred embodiment, the molar ratio of the first intermediate to the 1,q-dibromosubstituted alkane is 1:(10-30). The molar ratio of the first intermediate to the 1,q-dibromosubstituted alkane includes, but is not limited to, the above range. Limiting it to the above range is beneficial to improving the utilization rate of each reaction raw material and increasing the yield of the second intermediate.

[0089] In a preferred embodiment, the molar ratio of the first intermediate to the second basic compound is 1:(4-6). The molar ratio of the first intermediate to the second basic compound includes, but is not limited to, the above range. Limiting it to the above range is beneficial to better utilize the nucleophilicity of the second basic compound, thereby improving the yield of the second intermediate.

[0090] In a preferred embodiment, the ratio of the first intermediate to the second solvent is 0.05 mmol:(4–16) mL. This ratio includes, but is not limited to, the range described above. Limiting it to this range helps provide suitable reaction conditions for each reactant, increases the solubility of the reactants in the second solvent, and facilitates the second reaction.

[0091] To further improve the reaction efficiency of the second reaction, further reduce the amount of by-products generated, and further increase the solubility of each reactant in the second solvent, preferably, the second basic compound includes, but is not limited to, a mixture of tetrabutylammonium bromide and potassium hydroxide, more preferably a mixture of tetrabutylammonium bromide and potassium hydroxide in a molar ratio of 1:(30-35); the second solvent includes, but is not limited to, one or more of the group consisting of chlorobenzene, 1,2-dichlorobenzene and 1,1,2,2,-tetrachloroethane.

[0092] In a preferred embodiment, the temperature of the second reaction is 50–70°C, and the time is 8–16 hours. The temperature and time of the second reaction include, but are not limited to, the above-mentioned ranges. Limiting them to the above-mentioned ranges is beneficial to improving the yield of the second intermediate and reducing the amount of by-products generated.

[0093] Using the preparation method provided in this application, according to the stoichiometric ratio, when the second intermediate has the structure shown in general formula (XII), the amount of triethyl phosphite is at least n+1 times the amount of the second intermediate (n is 0 or 1); when the second intermediate has the structure shown in general formula (XIII), the amount of triethyl phosphite is at least x times the amount of the second intermediate (x is 2 or 3).

[0094] In a preferred embodiment, the molar ratio of the second intermediate to triethyl phosphite is 1:(15-25). The molar ratio of the second intermediate to triethyl phosphite includes, but is not limited to, the range described above. Limiting it to this range is beneficial for improving the utilization rate of each reactant and increasing the yield of the third intermediate.

[0095] In a preferred embodiment, the ratio of the second intermediate to the third solvent is 0.05 mmol:(4–16) mL. This ratio includes, but is not limited to, the range described above. Limiting it to this range helps provide suitable reaction conditions for each reactant, increases the solubility of each reactant in the third solvent, and facilitates the progress of the third reaction.

[0096] To further increase the solubility of each reactant in the third solvent and further increase the yield of the third intermediate, preferably, the third solvent includes, but is not limited to, one or more of the group consisting of 1,2-dichlorobenzene, 1,2-dichlorobenzene and 1,1,2,2,-tetrachloroethane.

[0097] In a preferred embodiment, the temperature of the third reaction is 130–150°C, and the time is 8–16 hours. The temperature and time of the third reaction include, but are not limited to, the above-mentioned ranges. Limiting them to the above-mentioned ranges is beneficial to improving the yield of the third intermediate and reducing the amount of by-products generated.

[0098] Using the preparation method provided in this application, according to the stoichiometric ratio, when the third intermediate has the structure shown in general formula (XIV), the amount of triethyl phosphite is at least 2n+2 times the amount of the second intermediate (n is 0 or 1); when the third intermediate has the structure shown in general formula (XV), the amount of triethyl phosphite is at least 2x times the amount of the second intermediate (x is 2 or 3).

[0099] In a preferred embodiment, the molar ratio of the third intermediate to trimethylbromosilane is 1:(5-15). The molar ratio of the third intermediate to trimethylbromosilane includes, but is not limited to, the above range. Limiting it to the above range is beneficial to improve the utilization rate of each reaction raw material and increase the yield of fullerene derivatives.

[0100] In a preferred embodiment, the ratio of the third intermediate to the fourth solvent is 0.05 mmol:(4–16) mL. This ratio includes, but is not limited to, the range described above. Limiting it to this range helps provide suitable reaction conditions for each reactant, increases the solubility of each reactant in the fourth solvent, facilitates the esterification reaction, and thus improves the yield of the fullerene derivative.

[0101] To further improve the solubility of trimethylbromosilane and the third intermediate, and to further improve the yield of fullerene derivatives, the fourth solvent preferably includes, but is not limited to, a mixture of 1,4-dioxane and chlorobenzene, more preferably a mixture of 1,4-dioxane and chlorobenzene in a volume ratio of 1:(10-30).

[0102] In a preferred embodiment, the temperature of the fourth reaction is 20–30°C, and the time is 8–16 hours. The temperature and time of the fourth reaction include, but are not limited to, the above ranges. Limiting them to the above ranges is beneficial to improving the yield of fullerene derivatives and reducing the amount of by-products generated, thereby facilitating subsequent separation and purification of fullerene derivatives.

[0103] A third aspect of this application also provides a perovskite solar cell, which includes a transparent conductive substrate 10, a first carrier transport layer 20, a perovskite active layer 30 doped with a fullerene derivative, a second carrier transport layer 40, and a cathode buffer layer 50 stacked sequentially. The perovskite solar cell also includes a metal electrode layer 60, which includes a plurality of metal electrodes 60, wherein a portion of the metal electrodes 60 are disposed on the side surface of the cathode buffer layer 50 away from the first carrier transport layer 20, and a portion of the metal electrodes 60 are disposed on the conductive surface of the transparent conductive substrate 10. The fullerene derivative includes one or more of the fullerene derivatives provided in this application, or one or more of the fullerene derivatives prepared by the preparation method of the fullerene derivatives provided in this application.

[0104] The fullerene derivatives provided in this application contain phosphate groups. When applied to perovskite solar cells, the hydrogen atoms (H) in the phosphate groups can form hydrogen bonds with the iodine atoms (I) in the perovskite active layer 30, while the oxygen atoms (O) can form coordinate bonds with the lead atoms (Pb) in the perovskite active layer 30. This can passivate the perovskite active layer 30 and improve its stability. Moreover, since the fullerene derivatives are electron-deficient, the iodine atoms have a relatively small binding force on the outer electrons. The fullerene derivatives can also form intermolecular forces with the iodine atoms in the perovskite active layer 30, which can adjust the longitudinal growth of the perovskite active material grains, thereby reducing crystal defects and improving the stability of the perovskite active layer 30.

[0105] Compared to other substituents, the use of the above-mentioned types of R is beneficial to improving the solubility of fullerene derivatives, improving the passivation performance of fullerene derivatives, thereby reducing the defect state density of perovskite films and thus improving the performance of perovskite solar cells.

[0106] Traditional perovskite solar cells do not contain the perovskite active layer 30 doped with fullerene derivatives as described in this application. Compared to traditional perovskite solar cells, doping the perovskite active layer 30 with the fullerene derivatives improves electron extraction efficiency, passivates defects in the perovskite active layer 30, and suppresses phase separation, thereby improving the photoelectric conversion efficiency and stability of the perovskite solar cell.

[0107] In a preferred embodiment, the perovskite active layer 30 further includes a perovskite active material, which includes, but is not limited to, ABX3, wherein A is CH3NH3. + NH=CHNH3 + Cs + 、or Rb + B is Pb 2+ Sn 2+ Or Ge 2+ X is Cl - ,Br - I - SCN - or COO - The aforementioned materials have low exciton binding energy, making it easy to generate free electron-hole pairs when excited by external light. Moreover, these materials have narrow band gaps and wide absorption spectra, which are beneficial for improving the absorption and utilization efficiency of solar energy when used as the active layer 30 of perovskite solar cells, thereby improving the absorption and utilization efficiency of solar energy in perovskite solar cells.

[0108] In a preferred embodiment, the doping amount of the fullerene derivative is 0.01 to 0.5 wt% based on the total weight of the perovskite active layer 30. The doping amount of the fullerene derivative includes, but is not limited to, the above range. Limiting it to the above range is beneficial to exert the passivation properties of the fullerene derivative, thereby improving the stability and power conversion efficiency of the perovskite solar cell.

[0109] This application does not specifically limit the transparent conductive substrate 10, as long as it has high light transmittance, good conductivity, and is easy to coat or deposit, it can be conductive glass with a conductive film commonly used in the art. In a preferred embodiment, the transparent conductive substrate 10 includes, but is not limited to, ITO conductive glass, FTO conductive glass, IZO conductive glass, or AZO conductive glass.

[0110] In a preferred embodiment, the material of the hole transport layer includes, but is not limited to, NiO. x One or more of the following: poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), [2-(9H-carbazole-9-yl)ethyl]phosphoric acid (2-PACz). Among them, nickel oxide NiO x It has a high hole mobility (approximately 0.141 cm). 2 V -1 s -1 It has a wide band gap, and as a material for the hole transport layer, it is beneficial to suppress charge recombination and improve hole extraction efficiency.

[0111] Electron transport materials should be able to both effectively transport electrons and block holes. In a preferred embodiment, the material of the electron transport layer includes, but is not limited to, SnO2, ZnO, and C. 60 One or more of PCBMs. Compared to other types, using the above-mentioned electron transport materials is beneficial to improving electron transport efficiency, thereby improving the photocurrent and photoelectric conversion efficiency of perovskite solar cells.

[0112] The material of the metal electrode 60 layer can be a metal material commonly used in the art. In a preferred embodiment, the material of the metal electrode 60 layer includes, but is not limited to, one or more of Ag, Cu, Al, and Au.

[0113] The hole transport layer collects and transports holes, thereby achieving effective electron-hole separation; the electron transport layer collects and transports electrons. In a preferred embodiment, the first carrier transport layer 20 is a hole transport layer, and the second carrier transport layer 40 is an electron transport layer. In this embodiment, the perovskite solar cell has an inverted structure, i.e., a pin-type perovskite solar cell.

[0114] In a preferred embodiment, the perovskite solar cell further includes an interface modification layer 70, which is disposed between the hole transport layer and the perovskite active layer 30; the material of the interface modification layer 70 includes the fullerene derivatives provided in this application.

[0115] Traditional perovskite solar cells do not contain the interface modification layer 70 provided in this application. Compared to traditional perovskite solar cells, when the fullerene derivative is applied to the interface modification layer 70, the phosphate groups therein can also react with commonly used hole transport materials such as NiO. x The interaction between inorganic metal oxides compensates for oxygen vacancies, thereby reducing interface defects between the hole transport layer and the perovskite active layer 30, which can improve the stability and energy conversion efficiency of perovskite solar cells.

[0116] To further improve the stability and energy conversion efficiency of perovskite solar cells, preferably, the thickness of the interface modification layer 70 is 1–5 nm.

[0117] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0118] Preparation Example 1

[0119] A method for preparing a fullerene derivative (compound 1), comprising:

[0120] (1) Under the catalysis of 2.2 mg and 0.01 mmol Pd(OAc)2, 36.0 mg and 0.05 mmol C 60 With 0.1 mmol o-iodoaniline (raw material B, Sigma-Aldrich (98% purity), 11.2 mg, 0.10 mmol of triethylenediamine hexahydrate (DABCO·6H2O) and 2.0 mg, 0.005 mmol of DPPE were reacted in 8 mL of chlorobenzene. The temperature of the first reaction was controlled at 130 °C for 24 h to obtain the first intermediate. The first intermediate has the following structure:

[0121]

[0122] (2) In the second basic compound n-Bu4N + In the presence of Br and KOH (molar ratio of 0.03:1), 40.6 mg and 0.05 mmol of the first intermediate obtained in step (1) above were reacted with 216 mg and 1.0 mmol of 1,4-dibromobutane in 8 mL of chlorobenzene in a second reaction, wherein the molar ratio of the first intermediate to the second basic compound was 1:5; the second reaction was carried out at 60 °C for 12 h to obtain the second intermediate; the chemical structure of the second intermediate is as follows:

[0123]

[0124] (3) The 47.3 mg and 0.05 mmol of the second intermediate obtained in step (2) above were reacted with 166 mg and 1 mmol of triethyl phosphite in 8 mL of 1,2-dichlorobenzene (o-DCB) to undergo a third reaction. The reaction temperature was controlled at 140 °C and the reaction time was 12 h to obtain the third intermediate. The third intermediate has the following structure:

[0125]

[0126] (4) In an argon atmosphere, 50.2 mg and 0.05 mmol of the third intermediate obtained in step (3) above were reacted with 76.5 mg and 0.5 mmol of trimethylbromosilane in 8.45 mL of a mixed solvent of 1,4-dioxane and chlorobenzene (volume ratio of 0.45:8). The temperature of the fourth reaction was controlled at room temperature (25°C) and the reaction time was 12 h. The solid obtained by vacuum distillation was dissolved in chloroform and washed with methanol to obtain a fullerene derivative (compound 1). The fullerene derivative (compound 1) has the following chemical structure:

[0127]

[0128] Its mass spectrometry data are as follows: C 70 H 14 NO3P[M] - 947.0710.

[0129] The yield of the fullerene derivative (compound 1) was 20%.

[0130] Preparation Example 2

[0131] (1) The difference between step (1) and preparation example 1 is only that different raw material B is used for preparation. In preparation example 2, raw material B is:

[0132] (Leyan reagent, 97% purity);

[0133] (2) Same as preparation example 1;

[0134] (3) Same as preparation example 1;

[0135] (4) Similar to the preparation example 1, a fullerene derivative (compound 2) was obtained, which has the following chemical structure:

[0136]

[0137] The yield of the fullerene derivative (compound 2) was 21%.

[0138] Preparation Example 3

[0139] (1) The difference between step (1) and preparation example 1 is only that different raw material B is used for preparation. In preparation example 3, raw material B is:

[0140] (Leyan reagent, 98% purity);

[0141] (2) Same as preparation example 1;

[0142] (3) Same as preparation example 1;

[0143] (4) Similar to the preparation example 1, a fullerene derivative (compound 3) was obtained, which has the following chemical structure:

[0144]

[0145] The yield of the fullerene derivative (compound 3) was 18%.

[0146] Preparation Example 4

[0147] (1) The difference between step (1) and preparation example 1 is only that different raw material B is used for preparation. In preparation example 4, raw material B is:

[0148] (Bide Pharmaceuticals, purity > 95%)

[0149] (2) Same as preparation example 1;

[0150] (3) Same as preparation example 1;

[0151] (4) Similar to the preparation example 1, a fullerene derivative (compound 4) was obtained, which has the following chemical structure:

[0152]

[0153] The yield of the fullerene derivative (compound 4) was 22%.

[0154] Preparation Example 5

[0155] (1) The difference between step (1) and preparation example 1 is only that: different raw material A is used for preparation, and C 60 The amount used is twice that of Preparation Example 1, wherein raw material A in Preparation Example 5 is:

[0156] (Henan Weitixi Chemical Technology Co., Ltd., purity 98%)

[0157] (2) Same as preparation example 1;

[0158] (3) Same as preparation example 1;

[0159] (4) Similar to the preparation example 1, a fullerene derivative (compound 5) was obtained, which has the following chemical structure:

[0160]

[0161] The yield of the fullerene derivative (compound 5) was 8%.

[0162] Preparation Example 6

[0163] (1) The difference between step (1) and preparation example 1 is only that: different raw material A is used for preparation, and C 60 The amount used is twice that of Preparation Example 1, wherein raw material A in Preparation Example 6 is:

[0164] In this process, raw material A is obtained by reacting 2,7-naphthyldiamine, iodine (2 equivalents), and sodium bicarbonate (3 equivalents) in methanol and aqueous solution (v:v = 9:1) for 0.5 h.

[0165] (2) Same as preparation example 1;

[0166] (3) Same as preparation example 1;

[0167] (4) Similar to the preparation example 1, a fullerene derivative (compound 6) was obtained, which has the following chemical structure:

[0168]

[0169] The yield of the fullerene derivative (compound 6) was 12%.

[0170] It should be noted that the overall yields of compounds 1 to 6 obtained in the preparation examples 1 to 6 of this application are based on the starting material C. 60 Calculated.

[0171] Device Example 1

[0172] A method for fabricating a pin-type perovskite solar cell includes the following steps:

[0173] (1) Prepare clean ITO conductive glass (purchased from Advanced Election Technology Co., Ltd., sheet resistance is 7Ω / sq);

[0174] (2) Preparation of solution:

[0175] Preparation of hole transport material dispersion: NiO x The nanoparticles were dissolved in deionized water to form a dispersion with a mass concentration of 10 mg / mL, and then sonicated for 5 min.

[0176] Preparation of perovskite active material precursor solution: 507 mg of PbI2 and 159 mg of MAI were dissolved in DMF:DMSO solvent (volume ratio 7:3) and stirred at 60 °C for 4 h; then 0.05 wt% of chlorobenzene solution of compound 1 was added, and the mixture was shaken to dissolve, thus obtaining perovskite active material precursor solution.

[0177] Preparation of electron transport material dispersion: 20 mg PCBM was dispersed in chlorobenzene to form a dispersion with a mass concentration of 20 mg / mL, and stirred at 25 °C for 4 h;

[0178] The cathodic buffer material dispersion was an isopropanol solution of copper oxychloride (BCP) (BCP, 0.5 mg / mL);

[0179] (3) Fabrication of perovskite solar cell devices:

[0180] The hole transport material dispersion was spin-coated onto the conductive surface of ITO conductive glass at 4000 rpm for 30 s, and then heated at 250 °C for 60 min to obtain NiO. x Hole transport layer;

[0181] Inside the glove box, a mixture of 20 μL of PbI2 and MAI was spin-coated onto NiO at 4000 rpm. x On the surface of the hole transport layer, spin coating time is 30s, 100μL of chlorobenzene solution is added dropwise at 20s for extraction, and heated at 100℃ for 10min to obtain perovskite active layer 30 doped with fullerene derivative (compound 1).

[0182] The PCBM dispersion was spin-coated onto the surface of the perovskite active layer 30 doped with fullerene derivative (compound 1) at a speed of 2000 rpm for 30 s to obtain the PCBM electron transport layer.

[0183] BCP was spin-coated onto the surface of the PCBM electron transport layer at a speed of 4000 rpm for 30 s to obtain the BCP cathode buffer layer 50, thus obtaining the first stacked structure (ITO / NiO). x Hole transport layer / perovskite active layer doped with compound 1 / PCBM electron transport layer / BCP cathode buffer layer;

[0184] A scraper is used to remove each layer of the ITO conductive glass surface in the first stacked structure, exposing the area on the conductive plane of the ITO conductive glass where the silver metal electrode 60 is to be disposed, so as to form the silver metal electrode 60 and obtain the second stacked structure.

[0185] The second layer structure described above is placed inside a photomask and transferred to a coating machine to... Ag was deposited at a high rate to obtain 60 layers of Ag metal electrodes with a thickness of 80 nm, thus completing the fabrication of the perovskite solar cell, the structure of which is as follows. Figure 1 As shown.

[0186] Device Example 2

[0187] The difference from Device Example 1 is that: Compound 2 is used to prepare the perovskite active material precursor solution and the perovskite active layer 30 doped with fullerene derivative (Compound 2). The remaining steps are the same as in Device Example 1.

[0188] Device Example 3

[0189] The difference from Device Example 1 is that: Compound 3 is used to prepare the perovskite active material precursor solution and the perovskite active layer 30 doped with fullerene derivative (Compound 3). The remaining steps are the same as in Device Example 1.

[0190] Device Example 4

[0191] The difference from Device Example 1 is that: Compound 4 is used to prepare the perovskite active material precursor solution and the perovskite active layer 30 doped with fullerene derivative (Compound 4). The remaining steps are the same as in Device Example 1.

[0192] Device Example 5

[0193] The difference from Device Example 1 is that: Compound 5 is used to prepare the perovskite active material precursor solution and the perovskite active layer 30 doped with fullerene derivative (Compound 5). The remaining steps are the same as in Device Example 1.

[0194] Device Example 6

[0195] The difference from Device Example 1 is that: Compound 6 is used to prepare the perovskite active material precursor solution and the perovskite active layer 30 doped with fullerene derivative (Compound 6). The remaining steps are the same as in Device Example 1.

[0196] Device Example 7

[0197] The hole transport material dispersion, perovskite active material precursor solution, electron transport material dispersion, and cathode buffer material dispersion are the same as those in Device Example 1. NiO x The hole transport layer, the perovskite active layer 30 doped with fullerene derivative (compound 1), the PCBM electron transport layer, the BCP cathode buffer layer 50, and the silver metal electrode 60 are the same as those in device embodiment 1.

[0198] The difference from device embodiment 1 is that: Figure 2 As shown, the perovskite solar cell also includes an interface modification layer 70, which is disposed on NiO. xBetween the hole transport layer and the perovskite active layer 30, the preparation of the precursor solution for the interface modification layer 70 includes: dispersing compound 1 obtained in Example 1 in chlorobenzene to obtain a compound 1 dispersion with a mass concentration of 1 mg / mL; the device fabrication process also includes: spin-coating 25 μL of the compound 1 dispersion onto NiO at a speed of 3000 rpm in a glove box. x On the surface of the hole transport layer, a spin coating time of 30s is used to obtain an interface modification layer 70; the thickness of the interface modification layer 70 is 2nm.

[0199] Device Comparison Example 1

[0200] The difference from device embodiment 1 is that the perovskite active layer 30 is not doped with fullerene derivatives (compound 1).

[0201] Device Comparison Example 2

[0202] The hole transport material dispersion, electron transport material dispersion, and cathode buffer material dispersion are the same as those in Device Example 1. NiO x The hole transport layer, PCBM electron transport layer, BCP cathode buffer layer 50, and silver metal electrode 60 are the same as in device embodiment 1. The difference from device embodiment 1 is that the perovskite active layer 30 is prepared using a fullerene derivative (compound A), which has the following structure:

[0203]

[0204] The perovskite solar cells prepared in the above-mentioned device embodiments 1 to 7 and device comparative examples 1 and 2 of this application were placed at 100mW / cm 2 Under illumination, the photovoltaic performance of the solar cells was tested. Table 1 lists the photovoltaic parameters of the solar cells fabricated in the corresponding device embodiments and device comparison examples.

[0205] Table 1

[0206] <![CDATA[V oc / V]]> <![CDATA[J sc / mA cm 2 ]]> FF / % PCE / % Device Example 1 1.08 23.55 78.46 18.49 Device Example 2 1.07 23.23 81.06 18.67 Device Example 3 1.07 22.93 78.62 17.91 Device Example 4 1.08 23.60 78.58 18.48 Device Example 5 1.09 23.11 82.07 19.07 Device Example 6 1.08 23.55 81.57 19.29 Device Example 7 1.10 24.00 83.89 20.53 Device Comparison Example 1 1.04 22.12 76.26 17.16 Device Comparison Example 2 1.04 22.10 75.31 16.92

[0207] The perovskite solar cells prepared in the above-described device embodiments 1 to 7 and device comparative examples 1 and 2 of this application were placed in a nitrogen atmosphere and 60% humidity environment for 500 hours to test their device stability. During the test, the solar cells were in a dark state environment. The normalized test results are shown in Table 2.

[0208] Table 2

[0209] PCE after 500 hours in a nitrogen atmosphere PCE after 500 hours in a 60% humidity environment Device Example 1 0.95 0.84 Device Example 2 0.96 0.85 Device Example 3 0.93 0.79 Device Example 4 0.94 0.83 Device Example 5 0.98 0.85 Device Example 6 0.99 0.86 Device Example 7 0.99 0.89 Device Comparison Example 1 0.85 0.70 Device Comparison Example 2 0.81 0.68

[0210] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0211] Comparing Device Examples 1 to 7 with Device Comparative Example 1, it can be seen that the fullerene derivative provided in this application contains phosphate groups. When applied to perovskite solar cells, the hydrogen atoms (H) in the phosphate groups can form hydrogen bonds with the iodine atoms (I) in the perovskite active layer 30, while the oxygen atoms (O) can form coordinate bonds with the lead atoms (Pb) in the perovskite active layer 30, thereby passivating the perovskite active layer 30 and improving its stability. Moreover, since the fullerene derivative is electron-deficient, the iodine atoms have a relatively small binding force on the outer electrons. The fullerene derivative can also form intermolecular forces with the iodine atoms in the perovskite active layer 30, which can adjust the longitudinal growth of the perovskite active material grains, thereby reducing crystal surface defects and improving the stability of the perovskite active layer 30.

[0212] Comparing device example 1 and device comparative example 2, it can be seen that, compared with other substituents, using the above-mentioned type of R is beneficial to improving the solubility of fullerene derivatives, beneficial to improving the passivation performance of fullerene derivatives, thereby beneficial to reducing the defect state density of perovskite thin films, and thus beneficial to improving the performance of perovskite solar cells.

[0213] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those described herein.

[0214] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fullerene derivative, characterized in that, The fullerene derivative is C 60 Derivatives, wherein the fullerene derivatives have the structure shown in general formula (I): （I）， Where n takes the value 0 or 1; When n is 1, Ar is selected from general formula (III) or general formula (IV): (III)、 (IV), When n is 0, Ar is selected from phenylene or naphthylene that share a carbon-carbon bond with a nitrogen-containing five-membered heterocycle; R is selected from H; m is 1; q is 2, 4 or 6.

2. The fullerene derivative according to claim 1, characterized in that, The fullerene derivative has any one of the following chemical structures: Compound 1 Compound 2 Compound 3 Compound 4 Compound 5 Compound 6.

3. A method for preparing a fullerene derivative, characterized in that, The preparation method includes: S1, under the catalysis of a catalyst, fullerene reacts with raw material A or raw material B, a first basic compound, and optional additives in a first solvent to obtain a first intermediate; the fullerene is C 60 The first intermediate has the structure shown in general formula (VIII): (VIII); The raw material A has the structure shown in general formula (X): （X）； The raw material B has the structure shown in general formula (XI): (XI); S2, in the presence of a second basic compound, the first intermediate undergoes a second reaction with a 1,q-dibromosubstituted alkane in a second solvent to give a second intermediate; the second intermediate has the structure shown in general formula (XII): (XII); S3, the second intermediate is reacted with triethyl phosphite in a third solvent to give a third intermediate; the third intermediate has the structure shown in general formula (XIV): (XIV); S4, in an inert atmosphere, the third intermediate is reacted with trimethylbromosilane in a fourth solvent to undergo a fourth reaction, followed by separation and purification to obtain the fullerene derivative; the fullerene derivative has the structure shown in general formula (I): （I）； Wherein, Ar, n, and q have the same meaning as in claim 1.

4. The method for preparing fullerene derivatives according to claim 3, characterized in that, When the fullerene undergoes the first reaction with raw material A, the molar ratio of the fullerene to raw material A is 1:(1-3); when the fullerene undergoes the first reaction with raw material B, the molar ratio of the fullerene to raw material B is (2-6):1; and / or, the molar ratio of the fullerene to the catalyst is 1:(0.05-0.3); and / or, the molar ratio of the fullerene to the first basic compound is 1:(1-3); and / or, the molar ratio of the fullerene to the optional additive is 1:(0.05-0.2); and / or, the molar ratio of the fullerene to the first solvent is 0.05 mmol:(4-16) mL.

5. The method for preparing fullerene derivatives according to claim 4, characterized in that, The catalyst is selected from palladium acetate; the first basic compound is selected from one or more of the group consisting of triethylenediamine hexahydrate, cesium carbonate, and 4-dimethylaminopyridine; the first solvent is selected from one or more of the group consisting of chlorobenzene, 1,2-dichlorobenzene, and 1,1,2,2-tetrachloroethane; the additive is selected from one or more of the group consisting of 1,2-bis(diphenylphosphine)ethane, triphenylphosphine, and lithium chloride.

6. The method for preparing the fullerene derivative according to claim 4, characterized in that, The temperature of the first reaction is 120–140°C, and the time is 20–28 h.

7. The method for preparing fullerene derivatives according to claim 3, characterized in that, The molar ratio of the first intermediate to the 1,q-dibromosubstituted alkane is 1:(10-30); and / or, the molar ratio of the first intermediate to the second basic compound is 1:(4-6); and / or, the molar ratio of the first intermediate to the second solvent is 0.05 mmol:(4-16) mL.

8. The method for preparing fullerene derivatives according to claim 7, characterized in that, The second basic compound is selected from a mixture of tetrabutylammonium bromide and potassium hydroxide; the second solvent is selected from one or more of the group consisting of chlorobenzene, 1,2-dichlorobenzene and 1,1,2,2-tetrachloroethane.

9. The method for preparing the fullerene derivative according to claim 7, characterized in that, The second alkaline compound is selected from a mixture of tetrabutylammonium bromide and potassium hydroxide in a molar ratio of 1:(30-35).

10. The method for preparing the fullerene derivative according to claim 7, characterized in that, The second reaction is carried out at a temperature of 50–70°C for 8–16 hours.

11. The method for preparing the fullerene derivative according to any one of claims 3 to 10, characterized in that, The molar ratio of the second intermediate to the triethyl phosphite is 1:(15-25); and / or the molar ratio of the second intermediate to the third solvent is 0.05 mmol:(4-16) mL.

12. The method for preparing the fullerene derivative according to claim 11, characterized in that, The third solvent is selected from one or more of the group consisting of 1,2-dichlorobenzene, 1,2-dichlorobenzene and 1,1,2,2,-tetrachloroethane.

13. The method for preparing the fullerene derivative according to claim 11, characterized in that, The third reaction is carried out at a temperature of 130–150°C for 8–16 hours.

14. The method for preparing the fullerene derivative according to claim 11, characterized in that, The molar ratio of the third intermediate to the trimethylbromosilane is 1:(5-15); and / or, the molar ratio of the third intermediate to the fourth solvent is 0.05mmol:(4-16)mL.

15. The method for preparing the fullerene derivative according to claim 14, characterized in that, The fourth solvent is selected from a mixture of 1,4-dioxane and chlorobenzene.

16. The method for preparing the fullerene derivative according to claim 15, characterized in that, The fourth solvent is selected from a mixture of 1,4-dioxane and chlorobenzene in a volume ratio of 1:(10-30).

17. The method for preparing the fullerene derivative according to claim 14, characterized in that, The fourth reaction is carried out at a temperature of 20–30°C for 8–16 hours.

18. A perovskite solar cell, characterized in that, The perovskite solar cell comprises a transparent conductive substrate (10), a first carrier transport layer (20), a perovskite active layer (30) doped with a fullerene derivative, a second carrier transport layer (40), and a cathode buffer layer (50) stacked sequentially. The perovskite solar cell further comprises a metal electrode layer, which includes a plurality of metal electrodes (60), wherein a portion of the metal electrodes (60) are disposed on the side surface of the cathode buffer layer (50) away from the first carrier transport layer (20), and a portion of the metal electrodes (60) are disposed on the conductive surface of the transparent conductive substrate (10). The fullerene derivative comprises one or more of the fullerene derivatives described in claim 1 or 2, or one or more of the fullerene derivatives prepared by the preparation method of any one of claims 3 to 17.

19. The perovskite solar cell according to claim 18, characterized in that, The doping amount of the fullerene derivative is 0.01 to 0.5 wt% of the total weight of the perovskite active layer.

20. The perovskite solar cell according to claim 18, characterized in that, The first carrier transport layer (20) is a hole transport layer, and the second carrier transport layer (40) is an electron transport layer.

21. The perovskite solar cell according to claim 20, characterized in that, The perovskite solar cell further includes an interface modification layer (70), which is disposed between the first carrier transport layer (20) and the perovskite active layer (30); the material of the interface modification layer (70) is the fullerene derivative.

22. The perovskite solar cell according to claim 21, characterized in that, The thickness of the interface modification layer (70) is 1-5 nm.

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