Solar cell and preparation method thereof, photovoltaic module, system and power utilization device

Abstract

The invention relates to a solar cell and a preparation method thereof, a photovoltaic module, a system and an electric device. The solar cell comprises a first electrode layer, an electron transport layer, an interface passivation layer, a perovskite light absorption layer and a second electrode layer which are arranged in a stacked mode. The interface passivation layer comprises an ionic polymer passivator, a main chain atom of the ionic polymer passivator is at least connected with a substituent R1, R1 comprises a positively charged nitrogen heterocyclic ring, and the ionic polymer passivator further comprises an anion X combined with the positively charged nitrogen heterocyclic ring.

Description

Technical Field

[0001] The present application relates to the field of material technology, and in particular to a solar cell and a preparation method thereof, a photovoltaic module, a system and an electrical device. Background Art

[0002] Perovskite materials are organic-inorganic metal halides ABX3, which have an octahedral structure, abundant raw material reserves, and can be widely synthesized artificially. Perovskite materials have many advantages such as high photoelectric absorption coefficient, long carrier diffusion length, and shallow defect energy level, which make perovskite materials have small photoelectric losses. Solar cells with perovskite materials as light absorption layers have the advantages of cost reduction and efficiency improvement, high weak light effect, and broad application scenarios. They are an excellent choice for the new generation of mass-produced photovoltaic cells.

[0003] However, the inhomogeneity of crystallization of perovskite materials during the preparation process will cause grain boundaries to appear between the surface and the bulk phase; the inherent problems of the crystallization process will cause defects such as vacancies, dislocations and dangling bonds. The existence of these defects will become new recombination centers, affecting the photoelectric conversion efficiency of solar cells. Forming a passivation layer on the surface of perovskite materials is a feasible technology to improve the above defects. The current passivators are mainly two-dimensional perovskites. However, practice has shown that this type of passivator will cause ion migration and ion diffusion into the bulk phase of the perovskite material in the light absorption layer during the use of solar cells, resulting in a decrease in the photoelectric conversion efficiency and stability of solar cells. Summary of the invention

[0004] Based on this, the present application aims to provide a solar cell and its preparation method, photovoltaic module, system and electrical device that can improve the photoelectric conversion efficiency and battery stability.

[0005] The first aspect of the present application provides a solar cell, comprising a first electrode layer, an electron transport layer, an interface passivation layer, a perovskite light absorption layer, and a second electrode layer stacked in sequence; the interface passivation layer comprises an ionic polymer passivator, and at least one substituent R is connected to the main chain atom of the ionic polymer passivator. 1 , R 1 The ionic polymer passivator comprises a positively charged nitrogen heterocycle, and the ionic polymer passivator further comprises an anion X combined with the positively charged nitrogen heterocycle.

[0006] The above-mentioned solar cell forms an interface passivation layer on the surface of the electron transport layer side of the perovskite light absorption layer. The interface passivation layer contains an ionic polymer passivator, which can passivate the defects on the surface of the perovskite light absorption layer. At the same time, the passivator is a polymer, and the possibility of ion migration and ion migration to the perovskite light absorption layer is reduced. The ionic polymer passivator has good electron conductivity and is arranged on one side of the electron transport layer without affecting electron transport. Therefore, it can improve the photoelectric conversion efficiency and stability of the solar cell.

[0007] In any embodiment of the present application, the positively charged nitrogen heterocycle includes at least one of a five-membered nitrogen heterocycle, a six-membered nitrogen heterocycle, a fused nitrogen heterocycle and an azaadamantane;

[0008] Optionally, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 4, and more preferably 1 to 3; more preferably, the five-membered nitrogen heterocycle includes at least one of pyrrole, pyrazole, imidazole, oxazole, thiazole and triazole;

[0009] Optionally, the number of nitrogen ring atoms in the six-membered nitrogen heterocyclic ring is 1 to 4, and more preferably 1 to 3; more preferably, the six-membered nitrogen heterocyclic ring includes at least one of pyridine, pyrimidine, monoazacyclohexane, pyridazine, pyrazine and piperazine;

[0010] Optionally, the fused nitrogen heterocycle includes at least one of the five-membered nitrogen heterocycle and the six-membered nitrogen heterocycle; more optionally, the fused nitrogen heterocycle includes at least one of indole, carbazole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, thienothiophene, furopyrrole, thienofuran, benzisoxazole, benzisothiazole, benzimidazole, quinoline, isoquinoline, 2,3-naphthyridine, quinoxaline, phenanthridine, primary pyridine, quinazoline, dibenzothiophene, phenazine and phenothiazine.

[0011] In any embodiment of the present application, the ring atoms in the positively charged nitrogen heterocycle are connected to the main chain atoms via a linking group L, and L is a single bond or includes a C1-C10 alkyl group.

[0012] In any embodiment of the present application, the ionic polymer passivator comprises a structural unit A, wherein at least one H is substituted by a group R 1 Substituted -CH2-CH2-, and R 1 The positively charged nitrogen heterocycle in is bonded with the anion X.

[0013] In any embodiment of the present application, the structural unit A has any one of the following structures A1 to A10, L is a single bond or includes a C1-C10 alkyl group;

[0014] Optionally, there are multiple structural units A in the ionic polymer passivator, and the multiple structural units A are each independently selected from any one of the following structures A1 to A10;

[0015]

[0016] In any embodiment of the present application, the repeating unit of the ionic polymer passivator is the structural unit A; or,

[0017] The ionic polymer passivator further comprises a structural unit B, wherein the structural unit B has a main chain and does not have a positively charged nitrogen heterocycle;

[0018] Optionally, the structural unit B has a main chain -CH2-CH2-, and the H in the structural unit B is unsubstituted or at least one H is substituted by a substituent R 2 Replacement, R 2 It does not have a positively charged nitrogen heterocyclic ring;

[0019] More optionally, R 2 It includes at least one of a five-membered ring, a six-membered ring and a condensed ring.

[0020] In any embodiment of the present application, X includes F - , Cl - Br - ,I - , TFSI, SCN, OCN, organic acid radical ions, OH - 、BF4 - and PF6 - Any one of;

[0021] Optionally, there are multiple X in the ionic polymer passivator, and the multiple Xs each independently include F - , Cl - Br - ,I - , TFSI, SCN, OCN, organic acid radical ions, OH - 、BF4 - and PF6 - Any one of .

[0022] In any embodiment of the present application, the thickness of the interface passivation layer is 5 nm to 80 nm, and can be 10 nm to 30 nm; and / or,

[0023] The weight average molecular weight of the ionic polymer passivator is 10,000 to 200,000, and can be 10,000 to 100,000; and / or,

[0024] The thickness of the perovskite light absorbing layer is 300nm to 1000nm, and can be optionally 400nm to 500nm.

[0025] The second aspect of the present application provides a method for preparing the solar cell of the first aspect of the present application, comprising the steps of forming a stacked arrangement of the first electrode layer, the electron transport layer, the interface passivation layer, the perovskite light absorption layer and the second electrode layer.

[0026] In any embodiment of the present application, the preparation method comprises the following steps:

[0027] forming the perovskite light absorbing layer on the second electrode layer;

[0028] forming the interface passivation layer on a surface of the perovskite light absorbing layer away from the second electrode layer;

[0029] forming the electron transport layer on a surface of the interface passivation layer away from the perovskite light absorbing layer; and

[0030] The first electrode layer is formed on a surface of the electron transport layer away from the interface passivation layer.

[0031] In any embodiment of the present application, the preparation method comprises the following steps:

[0032] forming the perovskite light absorbing layer on the second electrode layer;

[0033] Applying a slurry containing an electron transport material and the ionic polymer passivator on a surface of the perovskite light absorbing layer away from the second electrode layer, forming a film of the slurry to form a stacked interface passivation layer and an electron transport layer on the perovskite light absorbing layer; and

[0034] The first electrode layer is formed on a surface of the electron transport layer away from the interface passivation layer.

[0035] The third aspect of the present application provides a photovoltaic assembly, comprising the solar cell provided in the first aspect of the present application.

[0036] A fourth aspect of the present application provides a photovoltaic system, comprising the photovoltaic assembly provided by the third aspect of the present application.

[0037] The fifth aspect of the present application provides an electrical device, comprising at least one selected from the solar cell provided in the first aspect of the present application and the photovoltaic module provided in the third aspect of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a schematic diagram of a solar cell according to an embodiment of the present application;

[0039] Figure 2 is a schematic diagram of a solar cell according to another embodiment of the present application;

[0040] Figure 3 is a schematic diagram of an electrical device using a solar cell as a power source according to an embodiment of the present application;

[0041] Figure 4 This is a schematic diagram of the preparation process of the solar cell of Example 1 of the present application;

[0042] Figure 5This is a schematic diagram of the preparation process of the solar cell of Example 2 of the present application;

[0043] Figure 6 This is a schematic diagram of the preparation process of the solar cell of Comparative Example 2 of the present application.

[0044] Description of reference numerals:

[0045] 1. Solar cell; 11. Transparent electrode; 12. Electron transport layer; 13. Interface passivation layer; 14. Perovskite light absorption layer; 15. Hole transport layer; 16. Counter electrode layer; 2. Electrical device. DETAILED DESCRIPTION

[0046] Hereinafter, the embodiments of the present application are specifically disclosed in detail with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there may be cases where detailed descriptions of well-known matters and repeated descriptions of actually the same structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0047] "Scope" disclosed in the present application is limited in the form of lower limit and upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The scope limited in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a specific parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following scope can be all expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present application, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0048] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0049] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0050] If there is no special explanation, all steps of the present application can be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0051] If there is no special explanation, the "include" and "comprising" mentioned in this application are open-ended. For example, the "include" and "comprising" may mean that other components not listed may also be included or included, or only the listed components may be included or included.

[0052] In the present application, the term "alkyl" refers to a monovalent residue formed by the loss of a hydrogen atom from a saturated hydrocarbon containing a primary (normal) carbon atom, a secondary carbon atom, a tertiary carbon atom, a quaternary carbon atom, or a combination thereof. A phrase containing the term, for example, "C1-C20 alkyl" refers to an alkyl containing 1 to 10 carbon atoms, and each occurrence may be independently C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, C9 alkyl, C10 alkyl, C12 alkyl, C15 alkyl, C20 alkyl. Suitable examples include, but are not limited to, methyl (Me, -CH3), ethyl (Et, -CH2CH3), 1-propyl (n-Pr, n-propyl, -CH2CH2CH3), 2-propyl (i-Pr, i-propyl, -CH(CH3)2), 1-butyl (n-Bu, n-butyl, -CH2CH2CH2CH3), 2-methyl-1-propyl (i-Bu, i-butyl, -CH2CH(CH3)2), 2-butyl (s-Bu, s-butyl, -CH(C H3)CH2CH3), 2-methyl-2-propyl (t-Bu, t-butyl, -C(CH3)3), 1-pentyl (n-pentyl, -CH2CH2CH2CH2CH3), 2-pentyl (-CH(CH3)CH2CH2CH3), 3-pentyl (-CH(CH2CH3)2), 2-methyl-2-butyl (-C(CH3)2CH2CH3), 3-methyl-2-butyl (-CH(CH3)CH(CH3)2), 3-methyl-1-butyl (- CH2CH2CH(CH3)2), 2-methyl-1-butyl (-CH2CH(CH3)CH2CH3), 1-hexyl (-CH2CH2CH2CH2CH2CH3), 2-hexyl (-CH(CH3)CH2CH2CH2CH3), 3-hexyl (-CH(CH2CH3)(CH2CH2CH3)), 2-methyl-2-pentyl (-C(CH3)2CH2CH2CH3), 3-methyl-2-pentyl (-CH(CH3)CH( 2), 2-methyl-3-pentyl (-CH(CH2CH3)CH(CH3)2), 2,3-dimethyl-2-butyl (-C(CH3)2CH(CH3)2), 3,3-dimethyl-2-butyl (-CH(CH3)C(CH3)3 and octyl (-(CH2)7CH3).

[0053] In the present application, the term "hydrocarbon group" refers to the group remaining after a hydrocarbon containing only carbon and hydrogen atoms loses a hydrogen atom (H), including the group remaining after a saturated alkane loses a hydrogen atom (i.e., an alkyl group) and the group remaining after an unsaturated alkane loses a hydrogen atom. Among them, the group remaining after an unsaturated alkane loses a hydrogen atom includes an alkenyl group.

[0054] In the present application, the term "three-dimensional perovskite" refers to a perovskite having a three-dimensional crystal structure with a BX6 (or CX6, DX6) octahedral framework, with the A-site cation occupying the vertex position.

[0055] The term "two-dimensional perovskite" refers to a class of layered perovskite materials in which the skeleton of the perovskite material is separated by layers of organic molecules.

[0056] The present application provides a solar cell in one embodiment, comprising a first electrode layer, an electron transport layer, an interface passivation layer, a perovskite light absorption layer, and a second electrode layer stacked in sequence; the interface passivation layer comprises an ionic polymer passivator, and at least one substituent R is connected to the main chain atom of the ionic polymer passivator. 1 , R 1 The ionic polymer passivating agent includes a positively charged nitrogen heterocycle and an anion X bonded to the positively charged nitrogen heterocycle.

[0057] It is understood that the perovskite light absorbing layer is a three-dimensional perovskite film. The perovskite material included in the perovskite light absorbing layer is a three-dimensional perovskite. The perovskite light absorbing layer can be prepared by a preparation method commonly used in the art, including but not limited to sol-gel method, coating, multi-source co-evaporation and other methods. It is understood that coating includes but is not limited to spin coating, slit coating, brush coating, rubbing coating, scraping coating, screen coating and spraying.

[0058] Due to the uneven crystallization of the perovskite material in the perovskite light absorption layer during the preparation process, grain boundaries appear on the crystal surface and in the bulk phase, and vacancies, dislocations and dangling bonds also appear. The existence of these defects will become new recombination centers, affecting the photoelectric conversion efficiency and stability of the battery.

[0059] In summary, the above-mentioned solar cell forms an interface passivation layer on the surface of the electron transport layer side of the perovskite light absorption layer. The interface passivation layer contains an ionic polymer passivator, which can passivate the defects on the surface of the perovskite light absorption layer. At the same time, the passivator is a polymer, and the possibility of ion migration and ion migration to the perovskite light absorption layer is reduced. The ionic polymer passivator has good electron conductivity and is arranged on one side of the electron transport layer without affecting electron transport. Therefore, it can improve the photoelectric conversion efficiency and stability of the solar cell.

[0060] It is understood that the structure of each layer of the solar cell can be directly displayed by scanning electron microscope testing of the cross-section of the cell. The presence of the ionic polymer passivator having the above structure can be determined by sampling the interface passivation layer of the cross-section and performing at least one of infrared and mass spectrometry tests, including but not limited to.

[0061] It is understood that the positively charged nitrogen heterocycle may contain other heteroatoms in addition to the nitrogen heteroatom, such as at least one of O and S. It is understood that in some examples, the positively charged nitrogen heterocycle may contain only nitrogen heteroatoms in addition to carbon atoms.

[0062] In some embodiments, the substituent R of the ionic polymer passivator is 1 In the embodiment, the positively charged nitrogen heterocycle includes at least one of a five-membered nitrogen heterocycle, a six-membered nitrogen heterocycle, a condensed nitrogen heterocycle and an azaadamantane.

[0063] It is understood that the five-membered nitrogen heterocycle and the six-membered nitrogen heterocycle can be aromatic heterocycles or non-aromatic heterocycles.

[0064] A fused ring means that there are at least two cyclic structures that share at least two ring-forming atoms. A fused nitrogen heterocycle means that the atoms constituting the fused ring contain N heteroatoms in addition to carbon atoms.

[0065] Optionally, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 4, and more preferably 1 to 3. As an example, the five-membered nitrogen heterocycle includes at least one of pyrrole, pyrazole, imidazole, oxazole, thiazole and triazole.

[0066] Optionally, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 4, and more preferably 1 to 3. As an example, the six-membered nitrogen heterocycle includes at least one of pyridine, pyrimidine, monoazacyclohexane, pyridazine, pyrazine and piperazine (also known as diazene).

[0067] Optionally, the fused nitrogen heterocycle includes at least one of the above-mentioned five-membered nitrogen heterocycle and the above-mentioned six-membered nitrogen heterocycle. Further, the number of rings of the fused nitrogen heterocycle may be 2 to 6. As an example, the fused nitrogen heterocycle includes at least one of indole, carbazole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, thienothiophene, furopyrrole, thienofuran, benzisoxazole, benzisothiazole, benzimidazole, quinoline, isoquinoline, 2,3-naphthyridine, quinoxaline, phenanthridine, primary pyridine, quinazoline, dibenzothiophene, phenazine and phenothiazine.

[0068] In some embodiments, the ring atoms in the positively charged nitrogen heterocycle are connected to the main chain atoms via a linker group L, and L is a single bond or includes a C1-C10 alkyl group.

[0069] L is a single bond, that is, the ring atom in the positively charged nitrogen heterocycle is directly connected to the main chain atom. It can be understood that the ring atom in the positively charged nitrogen heterocycle can be a nitrogen atom or a non-nitrogen atom.

[0070] In other embodiments, L is not a single bond. Further, the substituent R of the ionic polymer passivator 1 In the embodiment, the ring atoms in the positively charged nitrogen heterocycle are connected to the main chain atoms through a linker group L, and L includes a C1-C10 alkyl group. It is understood that the ring atoms in the positively charged nitrogen heterocycle can be nitrogen atoms or non-nitrogen atoms. It is understood that the C1-C10 alkyl group can be substituted or unsubstituted. As an example, the C1-C10 alkyl group can be (CH2)n-, where n is an integer between 1 and 10.

[0071] In some embodiments, the ionic polymer passivator comprises a structural unit A, wherein the structural unit A is a unit in which at least one H is substituted with a group R 1 Substituted -CH2-CH2-, and R 1 The positively charged nitrogen heterocycle in is bound to an anion X.

[0072] Further, the structural unit A has any one of the following structures A1 to A10. Optionally, there are multiple structural units A in the ionic polymer passivator, and the multiple structural units A are each independently selected from any one of the following structures A1 to A10. Wherein, L is a single bond or includes a C1-C10 alkyl group.

[0073]

[0074] In some embodiments, the main chain of the ionic polymer passivating agent is a carbon chain.

[0075] In some embodiments, the repeating unit of the ionic polymer passivator is the structural unit A.

[0076] Further, as an example, L is a single bond, and the structure of the ionic polymer passivator is shown in the following formulas 1 to 10:

[0077]

[0078] Among them, the abbreviations of the passivating agents of Formulas 1 to 5 are PVIm-X (Formula 1), PVPy-X (Formula 2), PVTz-X (Formula 3), P4VPip-X (Formula 4), and PVDI-X (Formula 5), ​​respectively; the abbreviations of the passivating agents of Formulas 6 to 10 are P2VP-OH (Formula 6), P2VP-X (Formula 7), P4VP-X (Formula 8), P4VP-OH (Formula 9), and PVDABCO-X (Formula 10), respectively.

[0079] In some other embodiments, the ionic polymer passivator may further include a structural unit B, wherein the structural unit B has a carbon main chain and does not have a positively charged nitrogen heterocycle. Further, the structural unit B has a main chain -CH2-CH2-, and the H in the structural unit B is not substituted or at least one H is substituted with a substituent R 2 Replacement, R 2 It does not have a positively charged nitrogen heterocycle.

[0080] Furthermore, R 2 Including but not limited to at least one of a five-membered ring, a six-membered ring and a fused ring. Optionally, the five-membered ring, the six-membered ring and the fused ring are rings without heteroatoms, or non-nitrogen heterocycles, or uncharged nitrogen heterocycles. As an example, R 2 Including phenyl.

[0081] As an example, the structure of the ionic polymer passivator including the structural unit B is shown in Formula 11; further, its repeating unit has the structure shown below, wherein 0<n<1, for example, n is 0.2, 0.4, 0.5, 0.8.

[0082]

[0083] Further, as an example, L is a methylene group, and the structure of the ionic polymer passivator is shown in Formula 12 below:

[0084]

[0085] In some embodiments, X includes F - , Cl - Br - ,I - , TFSI (bis(trifluoromethanesulfonyl)imide) ion, SCN, OCN, organic acid ion, OH - 、BF4 - and PF6 - Optionally, there are multiple X in the ionic polymer passivator, and the multiple Xs independently include F - , Cl - Br - ,I - , TFSI, SCN, OCN, organic acid radical ions, OH - 、BF4 - and PF6 - Any one of .

[0086] Further, the organic acid radical ion includes at least one of carboxylate ion, sulfonate ion, sulfinate ion, thiol ion, phosphonate ion and phosphinate ion. As an example, the carboxylate ion includes but is not limited to CH3COO - and HCOO- At least one of .

[0087] In some of the embodiments, the weight average molecular weight of the ionic polymer passivator is 10,000 to 200,000; optionally, the weight average molecular weight of the ionic polymer passivator is 10,000 to 100,000, 50,000 to 100,000, 10,000 to 50,000 or 10,000 to 30,000.

[0088] In some of the embodiments, the thickness of the interface passivation layer is 5nm to 80nm; as an example, the thickness of the interface passivation layer may be 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 40nm, 60nm, 70nm, 80nm; it can be selected from 10nm to 50nm, 10nm to 30nm or 15nm to 25nm, or a range consisting of any two end values.

[0089] In some embodiments, the thickness of the perovskite light absorbing layer is 300nm to 1000nm. As an example, the thickness of the perovskite light absorbing layer is 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm, 1000nm; optionally, 400nm to 500nm.

[0090] Furthermore, the perovskite material in the above perovskite light absorbing layer has a general formula of ABX3 or A2CDX6; the A ion is a monovalent cation, the B ion is a divalent metal cation, the C ion is a monovalent metal cation, the D ion is a trivalent metal cation, and the X ion is a monovalent anion.

[0091] Optionally, the A ion includes at least one of an organic cation and a metal cation. More preferably, the organic cation includes at least one of an organic amine ion, a formamidine group (FA) and an imidazole group; More preferably, the metal cation includes Li + 、Na + , K + , Rb + and Cs + Further, the organic amine ion includes at least one of methylamine (MA), ethylamine, propylamine, butylamine, pentylamine and hexylamine.

[0092] Optionally, the B ions include Pb 2+ Sn 2+ 、Be 2+ Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ 、Zn 2+ ,Ge 2+ , Fe 2+ 、Co 2+ , Cu2+ and Ni 2+ More preferably, the B ions include Pb 2+ and Sn 2+ One or both of the following.

[0093] Optionally, the C ions include Cs + 、Ag + , K + And Ru + At least one of .

[0094] Optionally, the D ions include Bi 3+ 、Ni 3+ , Fe 3+ and Cu 3+ At least one of;

[0095] Optionally, the X ions include F - , Cl - Br - and I - At least one of; Optionally, the X ions include Cl - Br - and I - At least one of .

[0096] It can be understood that the perovskite material in the above-mentioned perovskite light absorbing layer can be selected from at least one of CsFAPbX3, CsMAPbX3, CsFAMAPbX3, CsPbX3, MAPbX3, FAPbX3, CsFAPbSnX3, CsMAPbSnX3, CsFAMAPbSnX3, CsPbSnX3, MAPbSnX3 and FAPbSnX3. Further, as an example, the perovskite material in the above-mentioned perovskite light absorbing layer can be selected from at least one of CsFAPbI3, CsPbI3, and FAPbI3.

[0097] As an example, the general formula of perovskite materials is as follows: Cs a FA b MA c Pb d Sn e I f Br g , among them, a=0~0.05, b=0.8~0.95, c=0~0.1, d=0.5~1, e=0~0.5, f=2.0~3, g=0~1, a+b+c=1, d+e=1, f+g=3.

[0098] As an example, the electron transport layer material can be but is not limited to at least one of the following materials and their derivatives: imide compounds, quinone compounds, fullerenes and their derivatives, methoxytriphenylamine-fluoroformamidine (OMeTPA-FA), PCBM ([6,6]-phenyl C61 butyric acid methyl ester), calcium titanate (CaTiO3), lithium fluoride (LiF), calcium fluoride (CaF2), poly (3,4-ethylenedioxythiophene): polystyrene sulfonic acid (PEDOT:PSS), poly 3-hexylthiophene (P3HT), triptycene as the core Triphenylamine (H101), 3,4-ethylenedioxythiophene-methoxytriphenylamine (EDOT-OMeTPA), N-(4-phenylamino)carbazole-spirobifluorene (CzPAF-SBF), polythiophene, metal oxides (metal elements are selected from Mg, Ni, Cd, Zn, In, Pb, Mo, W, Sb, Bi, Cu, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, or Cr), silicon oxide (SiO2), strontium titanate (SrTiO3), and cuprous thiocyanate (CuSCN).

[0099] Optionally, the solar cell may further include a hole blocking layer between the first electrode layer and the electron transport layer.

[0100] The hole blocking layer material may include, but is not limited to, BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline).

[0101] In a specific example, the electron transport layer adopts a PCBM layer, and the hole blocking layer adopts a BCP layer. The BCP layer serves as a passivation layer of the electron transport layer. The BCP molecular structure contains N atoms with lone pairs of electrons, which can effectively passivate the surface defects of the PCBM layer, promote the transfer and separation of charges at the interface, and help eliminate the current hysteresis of the battery device.

[0102] It is understood that the solar cell may also include a hole transport layer between the second electrode layer and the perovskite light absorption layer. Further, optionally, the solar cell may also include an electron blocking layer between the second electrode layer and the hole transport layer.

[0103] In some embodiments, the thickness of the hole transport layer is 10 nm to 200 nm. Further, the thickness of the hole transport layer is 10 nm to 100 nm, or 30 nm to 100 nm.

[0104] As an example, the hole transport layer material may be, but is not limited to, at least one of the following materials and their derivatives: 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), polytriarylamine (PTAA), NiOx (nickel oxide), poly-3,4-ethylenedioxythiophene:polystyrene sulfonate (PEDOT:PSS), WO3, etc. One or more materials that can transport holes and block electrons. The electron blocking layer material may be a known material.

[0105] It can be understood that in order to enable light to be effectively transmitted to the perovskite light absorption layer, at least one electrode in the solar cell is set as a transparent electrode and the other is a counter electrode layer.

[0106] It can be understood that the solar cell includes a regular structure and a trans structure in terms of structure. Optionally, the first electrode is a transparent electrode. For example, the first electrode layer or the second electrode layer is a transparent electrode.

[0107] For a formal structure, as an example, Figure 1 As shown, the solar cell includes a transparent electrode 11 and an electron transport layer 12, an interface passivation layer 13, a perovskite light absorption layer 14, a hole transport layer 15 and a counter electrode layer 16 sequentially stacked on the transparent electrode 11. The first electrode layer is a transparent electrode, the second electrode layer is a counter electrode layer, and the interface passivation layer can be disposed between the perovskite light absorption layer and the electron transport layer.

[0108] For the trans structure, as an example, Figure 2 As shown, the solar cell includes a transparent electrode 11 and a hole transport layer 15, a perovskite light absorption layer 14, an electron transport layer 12, an interface passivation layer 13 and a counter electrode layer 16 sequentially stacked on the transparent electrode 11. Among them, the second electrode layer is a transparent electrode, and the first electrode layer is a counter electrode layer.

[0109] The transparent electrode may be a transparent conductive metal oxide electrode. As an example, the material of the transparent electrode may be, for example, transparent conductive glass such as FTO, ITO, AZO, BZO, and IZO. It is understandable that in addition to using glass as a substrate, the transparent electrode may also use a transparent flexible substrate. Specifically, the material of the transparent flexible substrate may be, for example, an organic polymer material, which may be mixed in different proportions by one or more of the following materials: polyvinyl alcohol (PVA), polyester (PET), polyimide (PI), polyethylene naphthalate (PEN), and polydimethylsiloxane (PDMS).

[0110] As an example, the material of the counter electrode layer is, but not limited to, an organic or inorganic conductive material or a mixture of the two in different proportions. As an example, the counter electrode layer is a metal electrode, such as a metal conductive material of gold Au, silver Ag, copper Cu, aluminum Al, nickel Ni, chromium Cr, bismuth Bi, platinum Pt, magnesium Mg, or a mixture thereof. As an example, the counter electrode layer is a transparent conductive metal oxide electrode, such as FTO, ITO, aluminum-doped zinc oxide AZO, etc.

[0111] The present application also provides a method for preparing the solar cell, comprising the steps of forming the first electrode layer, the electron transport layer, the interface passivation layer, the perovskite light absorption layer and the second electrode layer in a stacked arrangement.

[0112] In some embodiments, the preparation method includes the following steps S11 to S14.

[0113] S11, forming a perovskite light absorption layer on the second electrode layer;

[0114] S12, forming an interface passivation layer on a surface of the perovskite light absorbing layer away from the second electrode layer;

[0115] S13, forming an electron transport layer on a surface of the interface passivation layer away from the perovskite light absorption layer.

[0116] S14, forming a first electrode layer on a surface of the electron transport layer away from the interface passivation layer.

[0117] Specifically, as an example, the solar cell is a trans type, and the preparation method thereof includes the following steps:

[0118] Step 1: Etching and cleaning the transparent electrode and drying;

[0119] Step 2: preparing a hole transport layer on the transparent electrode;

[0120] Step 3: Preparing a perovskite light absorption layer on the hole transport layer;

[0121] Step 4: preparing the above-mentioned interface passivation layer on the perovskite light absorption layer;

[0122] Step 5: preparing an electron transport layer on the interface passivation layer;

[0123] Step 5: Prepare a second electrode layer on the electron transport layer.

[0124] In some embodiments, the preparation method includes the following steps S21 to S23.

[0125] S21, forming a perovskite light absorption layer on the second electrode layer;

[0126] S22, coating a slurry containing an electron transport material and an ionic polymer passivator on a surface of the perovskite light absorbing layer away from the second electrode layer, forming a film of the slurry, and forming a stacked interface passivation layer and an electron transport layer on the perovskite light absorbing layer.

[0127] Since the slurry contains both electron transport material and ionic polymer passivator, and the ionic polymer passivator is a polymer with a larger weight average molecular weight than the electron transport material, when the slurry is formed into a film, the ionic polymer passivator is preferentially solidified to form on the surface of the perovskite light absorption layer and form an interface passivation layer, and the electron transport material is then solidified on the interface passivation layer.

[0128] Furthermore, the slurry includes an ionic polymer passivator, an electron transport material and an organic solvent.

[0129] Furthermore, the electron transport material in the slurry may be at least one of PCBM, fullerene and derivatives thereof.

[0130] As an example, the organic solvent includes, but is not limited to, at least one of IPA (isopropyl alcohol) and THF (tetrahydrofuran).

[0131] Optionally, the mass ratio of the ionic polymer passivator to the electron transport material in the slurry is 1:100 to 1:10. As an example, the mass ratio may be 1:100, 1:90, 1:80, 1:70, 1:60, 1:50, 1:40, 1:30, 1:20, or 1:10.

[0132] S23, forming a first electrode layer on a surface of the electron transport layer away from the interface passivation layer.

[0133] In some examples, the method for preparing the above-mentioned perovskite light absorption layer includes the following steps: mixing material A, BX2 and a solvent to obtain a perovskite precursor solution; then coating the perovskite precursor solution on a corresponding substrate, annealing, and obtaining a perovskite light absorption layer.

[0134] The above-mentioned first electrode, hole transport layer, electron transport layer and second electrode can be prepared by the commonly used preparation methods in the art, including but not limited to solution method and solid deposition method. The solution method includes any one of spin coating, spray coating, scraper coating and slit coating, and the solid deposition method includes any one of vacuum evaporation, sputtering deposition, plasma deposition and ion deposition.

[0135] An embodiment of the present application further provides a photovoltaic module, which includes the above-mentioned solar cell.

[0136] The solar cell has high light conversion efficiency and good stability, and can improve the efficiency of photovoltaic modules.

[0137] The above photovoltaic module includes one or more solar cells, which can be selected according to the specific application scenario; further, the above photovoltaic module includes multiple solar cells, and the multiple solar cells are connected in series or in parallel to form a battery cell.

[0138] In some of the embodiments, the photovoltaic module further includes a photovoltaic glass layer, a bonding layer and a back sheet.

[0139] Adhesive layers are respectively arranged on the two surfaces of the solar cell, a back plate is arranged on the surface of one of the adhesive layers away from the solar cell, and a photovoltaic glass layer is arranged on the surface of the other adhesive layer away from the solar cell.

[0140] The photovoltaic glass layer and the back panel are used to protect the solar cells, and they have the functions of sealing, insulation and waterproofing; the bonding layer plays the role of bonding the photovoltaic glass layer to the battery cell, and bonding the back panel to the battery cell.

[0141] Optionally, the photovoltaic glass layer is made of tempered glass, the back panel is made of TPT (polyvinyl fluoride) or TPE (thermoplastic elastomer), and the adhesive layer is made of EVA (polyethylene-polyvinyl acetate copolymer).

[0142] Furthermore, the above photovoltaic assembly also includes a junction box and an outer frame.

[0143] The junction box is used to protect the power generation system of the entire photovoltaic module. It is equivalent to a current transfer station. When a battery cell short-circuits, the junction box will automatically disconnect the short-circuited battery string.

[0144] The outer frame can support and protect the entire photovoltaic module. The frame can be made of aluminum alloy, which has excellent strength and corrosion resistance.

[0145] Furthermore, the connection between the frame and other parts of the photovoltaic module is bonded and sealed by silicone. The photovoltaic module can convert solar energy into electrical energy, or send it to a battery for storage, or drive a load to work.

[0146] In some embodiments, the photovoltaic component is a solar panel.

[0147] An embodiment of the present application further provides a photovoltaic system, comprising the above-mentioned photovoltaic module.

[0148] The photovoltaic system utilizes the photovoltaic effect of the solar cells in the photovoltaic modules to directly convert solar radiation energy into electrical energy with high efficiency; further, the photovoltaic system is a photovoltaic power generation system.

[0149] Photovoltaic modules are the core part of photovoltaic power generation systems. The above photovoltaic system includes one or more photovoltaic modules, which can be selected according to specific application scenarios; further, when the above photovoltaic system includes multiple photovoltaic modules, the multiple photovoltaic modules form a photovoltaic array.

[0150] The above photovoltaic system can be an independent photovoltaic power generation system or a grid-connected photovoltaic power generation system.

[0151] An independent photovoltaic power generation system includes a photovoltaic array, a battery pack, a charging controller, a power electronic converter (inverter), a load, etc. Its working principle is that the solar radiation energy is first converted into electrical energy through the photovoltaic array, and then converted by the power electronic converter to supply power to the load. At the same time, the excess electrical energy is stored in the energy storage device in the form of chemical energy after passing through the charging controller. In this way, when the sunshine is insufficient, the energy stored in the battery can be converted into AC 220V, 50Hz electrical energy after being stepped up by the power electronic inverter, filtering and power frequency transformer for use by the AC load.

[0152] The grid-connected photovoltaic power generation system includes a photovoltaic array, a high-frequency DC / DC boost circuit, a power electronic converter (inverter) and system monitoring. Its working principle is that the solar radiation energy is converted by the photovoltaic array, and then converted into high-voltage DC power by high-frequency DC conversion, and then inverted by the power electronic inverter to output a sinusoidal AC current with the same frequency as the grid voltage to the grid.

[0153] The above two photovoltaic power generation systems have their own characteristics and can be selected according to specific application scenarios.

[0154] One embodiment of the present application provides an electrical device, including the above-mentioned solar cell or the above-mentioned photovoltaic module.

[0155] In some of the embodiments, the solar cell or photovoltaic module can be used as a power source for an electrical device, or can be used as an energy storage unit for an electrical device.

[0156] Furthermore, the above-mentioned electrical devices may include mobile devices, such as mobile phones, laptop computers, etc., electric vehicles, electric trains, ships and satellites, etc., but are not limited thereto.

[0157] Figure 3 The power consumption device 2 is used as an example. The power consumption device 2 is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle.

[0158] In order to make the technical problems, technical solutions and beneficial effects solved by the present application clearer, the present application will be further described in detail below in conjunction with the embodiments and drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its applications. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0159] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0160] 1. Device Preparation

[0161] Sources of raw materials: The passivating agents used in the examples and comparative examples were all commercially available.

[0162] The repeating unit of the passivating agent in Example 16 is shown in the following formula 11, and the molar ratio of the two structural units in the repeating unit is 1:1. The weight average molecular weight is 20,000, and X is Cl.

[0163] n is 0.5.

[0164] The structure of the passivating agent in Example 17 is shown in Formula 12. The weight average molecular weight is 20,000, and X is Cl.

[0165]

[0166] Example 1

[0167] like Figure 4 As shown, a method for preparing a solar cell device with an inverted structure is as follows:

[0168] An oxide film with a thickness of 30 nm was formed on the ITO glass by magnetron sputtering as a nickel hole transport layer.

[0169] A 1.4 mol / L perovskite precursor solution (the solvent is DMF and DMSO in a volume ratio of 4:1) is coated on the nickel oxide hole transport layer to form a 450 nm thick perovskite film. 0.05 FA 0.90 MA 0.05 PbI3.

[0170] An ionic polymer passivator solution (solvent is isopropanol, concentration is 1 mg / mL) is spin-coated on the surface of the perovskite film, and after the passivator is formed into a film at 3000 rpm, an interface passivation layer is formed on the surface of the perovskite. The specific type of the ionic polymer passivator and the thickness of the interface passivation layer are shown in Table 1.

[0171] A C60 layer (graphene layer) having a thickness of 30 nm was formed on the interface passivation layer by thermal evaporation as an electron transport layer.

[0172] A 5 nm thick BCP layer was formed by thermal evaporation on the electron transport layer as a hole blocking layer. Figure 4 In the figure, the stack of C60 layer and BCP layer is represented by C60 / BCP.

[0173] A copper electrode having a thickness of 100 nm was formed on the hole blocking layer by thermal evaporation.

[0174] Example 2

[0175] like Figure 5 As shown, a method for preparing a solar cell device with an inverted structure is as follows:

[0176] A nickel oxide hole transport layer with a thickness of 30 nm was formed on the ITO glass by magnetron sputtering.

[0177] A 1.4 mol / L perovskite precursor solution (the solvent is DMF and DMSO in a volume ratio of 4:1) is coated on the nickel oxide hole transport layer to form a 450 nm thick perovskite film. 0.05 FA 0.90 MA 0.05 PbI3.

[0178] A mixed solution of PCBM and ionic polymer passivator (solvent is THF tetrahydrofuran isopropanol, concentration of PCBM is 10 mg / mL and concentration of ionic polymer passivator is 0.1 mg / mL) is spin-coated on the surface of the perovskite film. Figure 5 After spin coating at 5000 rpm, an interface passivation layer (component is an ionic polymer passivator) is formed on the surface of the perovskite, and a PCBM layer with a thickness of about 30 nm is formed on the interface passivation layer as an electron transport layer. The specific types of the ionic polymer passivator and the thickness of the interface passivation layer are shown in Table 1.

[0179] A copper electrode with a thickness of 100 nm was formed on the electron transport layer by thermal evaporation.

[0180] Examples 1 to 17

[0181] It is basically the same as Example 1 or Example 2 (see "similar structure" in Table 1 for details), the only difference is that other types of ionic polymer passivators of equal mass are used to replace the ionic polymer passivator in Example 1, as shown in Table 1.

[0182] Embodiments 18 to 19

[0183] Compared with Example 8, the only difference is that the thickness of the interface passivation layer is controlled differently (controlled by controlling the amount of the ionic polymer passivator solution spin-coated).

[0184] Comparative Example 1

[0185] It is basically the same as Example 1, except that the interface passivation layer in Example 1 is omitted.

[0186] Comparative Example 2

[0187] The ionic polymer passivator in Example 3 is used in a solar cell device with a formal structure, specifically, the passivator is used between the perovskite film and the hole transport layer.

[0188] like Figure 6 As shown, a method for preparing a solar cell device with a formal structure is as follows:

[0189] A 30 nm thick tin oxide film was formed on the ITO glass by magnetron sputtering as an electron transport layer.

[0190] A 1.4 mol / L perovskite precursor solution (the solvent is DMF and DMSO in a volume ratio of 4:1) is coated on the electron transport layer to form a 450 nm thick perovskite film. 0.05 FA 0.90 MA 0.05 PbI3.

[0191] An ionic polymer passivator solution (solvent is isopropanol, concentration is 1 mg / mL) is spin-coated on the surface of the perovskite film, and after the passivator is formed into a film at 3000 rpm, an interface passivation layer is formed on the surface of the perovskite. The specific type of the ionic polymer passivator and the thickness of the interface passivation layer are shown in Table 1.

[0192] A Spiro-OMeTAD layer with a thickness of 80 nm was formed on the interface passivation layer by blade coating as a hole transport layer.

[0193] A gold electrode with a thickness of 100 nm was formed on the hole transport layer by thermal evaporation.

[0194] Comparative Example 3

[0195] The method is basically the same as Example 1, except that the ionic polymer passivator in the ionic polymer passivator solution in Example 1 is replaced by the monomer salt 1 of the same mass.

[0196] Comparative Example 4

[0197] The method is basically the same as Example 1, except that the ionic polymer passivator in the ionic polymer passivator solution in Example 1 is replaced by the monomer salt 2 of the same mass.

[0198] The structures of monomer salt 1 and monomer salt 2 are as follows:

[0199]

[0200] Comparative Example 5

[0201] The method is basically the same as Example 1, except that the ionic polymer passivator in the ionic polymer passivator solution in Example 1 is replaced by a passivator of equal mass.

[0202] The repeating unit of the passivator in Comparative Example 5 is shown in Formula 13 below, and the molar ratio of the two structural units in the repeating unit is 1:1 (n is 0.5), the weight average molecular weight is 20,000, and X is Cl.

[0203]

[0204] Comparative Example 6

[0205] The method is basically the same as Example 1, except that a two-dimensional perovskite film of the same thickness is used as the interface passivation layer. The two-dimensional perovskite film is specifically PEA2PbI4.

[0206] 2. Performance Test

[0207] 1) IV performance test to obtain open circuit voltage and initial efficiency

[0208] Specific steps: Store the obtained battery away from light. The test of solar cells (IV test) uses Guangyan's solar simulator, which complies with the national standard IEC61215 for testing. The intensity of light is calibrated using crystalline silicon solar cells to reach the intensity of one sun (AM 1.5G, 100mW / cm 2 ), the battery is connected to a digital source meter, and an IV curve is obtained under light to obtain the photoelectric conversion efficiency of the solar cells prepared in the above embodiments and comparative examples.

[0209] According to the IV curve and the data fed back by the test equipment, the short-circuit current Jsc (unit: mA / cm 2), open circuit voltage Voc (unit V), maximum light output current Jmpp (unit mA) and maximum light output voltage Vmpp (unit V). The fill factor FF of the cell is calculated by the formula FF = Jsc × Voc / (Jmpp × Vmpp), unit %. The photoelectric conversion efficiency PCE (i.e. initial efficiency) of the cell is calculated by the formula PCE = Jsc × Voc × FF / Pw, unit %; Pw represents the input power, unit mW.

[0210] The initial efficiency results are shown in Table 1.

[0211] 2) Efficiency change rate after 72 hours of maximum power illumination aging

[0212] The conditions for 72 hours of maximum power light aging are as follows:

[0213] Efficiency change rate = (efficiency after 72 hours of maximum power light aging - initial efficiency before aging) * 100% / initial efficiency before aging. The test method of efficiency after 72 hours of maximum power light aging is the same as that of initial efficiency. The results are shown in Table 1.

[0214] Table 1

[0215]

[0216]

[0217] As can be seen from Table 1, the open circuit voltage, initial efficiency and efficiency change rate after 72 hours of maximum power light aging of the solar cells prepared in Examples 1 to 20 are significantly higher than those in the comparative examples.

[0218] Comparative Example 1 did not use a passivator to passivate the perovskite film, and the passivators used in Comparative Examples 3 and 4 were monomer salts, and their efficiency change rates after 72 hours of maximum power light aging were much lower, indicating that their passivation effects were very poor, even lower than that of Comparative Example 1 without passivation. Comparative Example 2 placed the passivator in Example 3 between the perovskite film and the hole transport layer, and its initial efficiency was significantly reduced.

[0219] Comparative Examples 5 to 6 all use other types of passivators. The results show that although the passivator in Comparative Example 5 can improve the stability of device efficiency, its improvement effect on the initial efficiency of the solar cell device is relatively small; the passivator in Comparative Example 6 does not improve the initial efficiency and stability of the solar cell device, but instead reduces them.

[0220] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A solar cell, characterized in that: The invention comprises a first electrode layer, an electron transport layer, an interface passivation layer, a perovskite light absorption layer and a second electrode layer which are stacked; the interface passivation layer comprises an ionic polymer passivator, and at least one substituent R is connected to the main chain atom of the ionic polymer passivator. 1 , R 1 The ionic polymer passivator comprises a positively charged nitrogen heterocycle, and the ionic polymer passivator further comprises an anion X combined with the positively charged nitrogen heterocycle.

2. The solar cell according to claim 1, characterized in that The positively charged nitrogen heterocycle includes at least one of a five-membered nitrogen heterocycle, a six-membered nitrogen heterocycle, a fused nitrogen heterocycle and an azaadamantane; Optionally, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 4, and more preferably 1 to 3; more preferably, the five-membered nitrogen heterocycle includes at least one of pyrrole, pyrazole, imidazole, oxazole, thiazole and triazole; Optionally, the number of nitrogen ring atoms in the six-membered nitrogen heterocyclic ring is 1 to 4, and more preferably 1 to 3; more preferably, the six-membered nitrogen heterocyclic ring includes at least one of pyridine, pyrimidine, monoazacyclohexane, pyridazine, pyrazine and piperazine; Optionally, the fused nitrogen heterocycle includes at least one of the five-membered nitrogen heterocycle and the six-membered nitrogen heterocycle; more optionally, the fused nitrogen heterocycle includes at least one of indole, carbazole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, thienothiophene, furopyrrole, thienofuran, benzisoxazole, benzisothiazole, benzimidazole, quinoline, isoquinoline, 2,3-naphthyridine, quinoxaline, phenanthridine, primary pyridine, quinazoline, dibenzothiophene, phenazine and phenothiazine.

3. The solar cell according to claim 1, characterized in that The ring atoms in the positively charged nitrogen heterocycle are connected to the main chain atoms via a connecting group L, and L is a single bond or includes a C1-C10 alkyl group.

4. The solar cell according to claim 1, characterized in that The ionic polymer passivator comprises a structural unit A, wherein at least one H is substituted by a R 1 Substituted -CH2-CH2-, and R 1 The positively charged nitrogen heterocycle in is bonded with the anion X.

5. The solar cell according to claim 4, characterized in that: The structural unit A has any one of the following structures A1 to A10, L is a single bond or includes a C1-C10 alkyl group; Optionally, there are multiple structural units A in the ionic polymer passivator, and the multiple structural units A are each independently selected from any one of the following structures A1 to A10; 6. The solar cell according to any one of claims 4 to 5, characterized in that: The repeating unit of the ionic polymer passivator is the structural unit A; or The ionic polymer passivator further comprises a structural unit B, wherein the structural unit B has a main chain and does not have a positively charged nitrogen heterocycle; Optionally, the structural unit B has a main chain -CH2-CH2-, and the H in the structural unit B is unsubstituted or at least one H is substituted by a substituent R 2 Replacement, R 2 It does not have a positively charged nitrogen heterocyclic ring; More optionally, R 2 It includes at least one of a five-membered ring, a six-membered ring and a condensed ring.

7. The solar cell according to any one of claims 1 to 5, characterized in that: X includes F - , Cl - Br - ,I - , TFSI, SCN, OCN, organic acid radical ions, OH - 、BF4 - and PF6 - Any one of; Optionally, there are multiple X in the ionic polymer passivator, and the multiple Xs each independently include F - , Cl - Br - ,I - , TFSI, SCN, OCN, organic acid radical ions, OH - 、BF4 - and PF6 - Any one of .

8. The solar cell according to any one of claims 1 to 5, characterized in that: The thickness of the interface passivation layer is 5 nm to 80 nm, and can be 10 nm to 30 nm; and / or, The weight average molecular weight of the ionic polymer passivator is 10,000 to 200,000, and can be selected from 10,000 to 100,000; and / or, The thickness of the perovskite light absorbing layer is 300nm to 1000nm, and can be optionally 400nm to 500nm.

9. A method for preparing a solar cell according to any one of claims 1 to 8, characterized in that: The method comprises the steps of forming the first electrode layer, the electron transport layer, the interface passivation layer, the perovskite light absorption layer and the second electrode layer which are stacked.

10. The method for preparing a solar cell according to claim 9, characterized in that: The preparation method comprises the following steps: forming the perovskite light absorbing layer on the second electrode layer; forming the interface passivation layer on a surface of the perovskite light absorbing layer away from the second electrode layer; forming the electron transport layer on a surface of the interface passivation layer away from the perovskite light absorption layer; and The first electrode layer is formed on a surface of the electron transport layer away from the interface passivation layer.

11. The method for preparing a solar cell according to claim 9, characterized in that: The preparation method comprises the following steps: forming the perovskite light absorbing layer on the second electrode layer; Applying a slurry containing an electron transport material and the ionic polymer passivator on a surface of the perovskite light absorbing layer away from the second electrode layer, forming a film of the slurry, and forming a stacked interface passivation layer and an electron transport layer on the perovskite light absorbing layer; and The first electrode layer is formed on a surface of the electron transport layer away from the interface passivation layer.

12. A photovoltaic module, characterized in that: The invention comprises the solar cell according to any one of claims 1 to 8.

13. A photovoltaic system, characterized in that: Comprising the photovoltaic module as claimed in claim 12.

14. An electrical device, characterized in that: The invention comprises at least one selected from the group consisting of the solar cell according to any one of claims 1 to 8 and the photovoltaic module according to claim 12.

Images