Solar cell and preparation method therefor, photovoltaic module, system and electric device

Abstract

The present application relates to a solar cell and a preparation method therefor, 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 stacked. The interface passivation layer comprises an ionic polymer passivator, a backbone atom of the ionic polymer passivator is linked to at least one 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

Solar cell and preparation method thereof, photovoltaic module, system and electrical device

[0001] Related applications

[0002] This application claims priority to the Chinese patent application filed with the China Patent Office on July 7, 2023, with application number 2023108368097, entitled “Solar cells and methods for their preparation, photovoltaic modules, systems and electrical devices”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] 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

[0004] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0005] Perovskite materials are organic-inorganic metal halides (ABX3) with an octahedral structure. The raw materials are abundant and can be widely synthesized. Perovskite materials offer numerous advantages, including high photoelectric absorption coefficients, long carrier diffusion lengths, and shallow defect levels, resulting in minimal photoelectric losses. Solar cells using perovskite materials as light-absorbing layers offer advantages such as reduced costs and increased efficiency, high low-light performance, and a wide range of applications, making them an excellent choice for the next generation of mass-produced photovoltaic cells.

[0006] However, the heterogeneity of crystallization during the perovskite preparation process can lead to the formation of grain boundaries between the surface and the bulk phase. Furthermore, inherent problems in the crystallization process can lead to the emergence of defects such as vacancies, dislocations, and dangling bonds. These defects can become new recombination centers, affecting the photovoltaic efficiency of solar cells. Forming a passivation layer on the surface of the perovskite material is a feasible technology to address these defects. Currently, passivators are primarily based on two-dimensional perovskites. However, practice has shown that these passivants can cause ion migration and diffusion into the bulk of the perovskite material in the light-absorbing layer during use in solar cells, resulting in reduced photovoltaic efficiency and stability.

[0007] Summary of the Invention

[0008] 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.

[0009] 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 the main chain atoms of the ionic polymer passivator are connected to at least one substituent R 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.

[0010] The above-mentioned solar cell forms an interfacial passivation layer on the surface of the electron transport layer side of the perovskite light absorption layer. The interfacial passivation layer contains an ionic polymer passivator, which can passivate defects on the surface of the perovskite light absorption layer. At the same time, the passivator is a polymer, and its ion migration and ion migration to the perovskite light absorption layer are reduced. The ionic polymer passivator has good electron conductivity and does not affect electron transport when it is arranged on the electron transport layer side. Therefore, it can improve the photoelectric conversion efficiency and stability of the solar cell.

[0011] 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.

[0012] In any embodiment of the present application, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 4.

[0013] In any embodiment of the present application, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 3.

[0014] In any embodiment of the present application, the five-membered nitrogen heterocycle includes at least one of pyrrole, pyrazole, imidazole, oxazole, thiazole and triazole.

[0015] In any embodiment of the present application, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 4.

[0016] In any embodiment of the present application, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 3.

[0017] In any embodiment of the present application, the six-membered nitrogen heterocycle includes at least one of pyridine, pyrimidine, monoazacyclohexane, pyridazine, pyrazine and piperazine.

[0018] In any embodiment of the present application, 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 idine, quinazoline, dibenzothiophene, phenazine and phenothiazine.

[0019] 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 linker group L, and L is a single bond or includes a C1-C10 alkyl group.

[0020] In any embodiment of the present application, the ionic polymer passivator includes 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 bound to the anion X.

[0021] In any embodiment of the present application, the structural unit A has any one of the following structures A1 to A10, and L is a single bond or includes a C1-C10 alkyl group.

[0022] In any embodiment of the present application, 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;

[0023] In any embodiment of the present application, the repeating unit of the ionic polymer passivator is the structural unit A.

[0024] In any embodiment of the present application, 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.

[0025] In any embodiment of the present application, 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 by R 2 Replacement, R 2 It does not have a positively charged nitrogen heterocycle.

[0026] In any embodiment of the present application, R 2 It includes at least one of a five-membered ring, a six-membered ring and a condensed ring.

[0027] 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 .

[0028] In any embodiment of the present application, 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 .

[0029] In any embodiment of the present application, the solar cell satisfies at least one of the following characteristics:

[0030] (1) The thickness of the interface passivation layer is 5 nm to 80 nm;

[0031] (2) The weight average molecular weight of the ionic polymer passivator is 10,000 to 200,000;

[0032] (3) The thickness of the perovskite light absorption layer is 300 nm to 1000 nm.

[0033] In any embodiment of the present application, the solar cell satisfies at least one of the following characteristics:

[0034] (1) The thickness of the interface passivation layer is 10 nm to 30 nm;

[0035] (2) The weight average molecular weight of the ionic polymer passivator is 10,000 to 100,000;

[0036] (3) The thickness of the perovskite light absorbing layer is 400 nm to 500 nm.

[0037] 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 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.

[0038] In any embodiment of the present application, the preparation method comprises the following steps:

[0039] forming the perovskite light absorbing layer on the second electrode layer;

[0040] forming the interface passivation layer on a surface of the perovskite light absorbing layer away from the second electrode layer;

[0041] forming the electron transport layer on a surface of the interface passivation layer away from the perovskite light absorbing layer; and

[0042] The first electrode layer is formed on a surface of the electron transport layer away from the interface passivation layer.

[0043] In any embodiment of the present application, the preparation method comprises the following steps:

[0044] forming the perovskite light absorbing layer on the second electrode layer;

[0045] 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 from the slurry to form the interface passivation layer and the electron transport layer stacked on the perovskite light absorbing layer; and

[0046] The first electrode layer is formed on a surface of the electron transport layer away from the interface passivation layer.

[0047] The third aspect of the present application provides a photovoltaic assembly, comprising the solar cell provided in the first aspect of the present application.

[0048] A fourth aspect of the present application provides a photovoltaic system, comprising the photovoltaic assembly provided by the third aspect of the present application.

[0049] 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.

[0050] The details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the disclosed drawings without any creative work.

[0052] FIG1 is a schematic diagram of a solar cell according to an embodiment of the present application;

[0053] FIG2 is a schematic diagram of a solar cell according to another embodiment of the present application;

[0054] FIG3 is a schematic diagram of an electrical device using a solar cell as a power source according to an embodiment of the present application;

[0055] FIG4 is a schematic diagram of the preparation process of the solar cell according to Example 1 of the present application;

[0056] FIG5 is a schematic diagram of the preparation process of the solar cell according to Example 2 of the present application;

[0057] FIG6 is a schematic diagram of the preparation process of the solar cell of Comparative Example 2 of the present application.

[0058] Description of reference numerals:

[0059] 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

[0060] The following detailed description of the embodiments of the present application is appropriately referred to the accompanying drawings. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repeated descriptions of substantially identical structures may be omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate understanding by those skilled in the art. In addition, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0061] " range " disclosed in the present application is limited in the form of lower limit and upper limit, and 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 special range. The scope limited in this way can be to include end value or not include end value, and can be arbitrarily combined, that is, any lower limit can form a range with any upper limit combination. For example, if the scope of 60-120 and 80-110 is listed for specific parameters, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range value 1 and 2 are listed, and if the maximum range value 3,4 and 5 are listed, then the following range can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this 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 all real numbers. For example, a numerical range of "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is simply an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this 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.

[0062] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0063] 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.

[0064] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating 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), indicating 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.

[0065] Unless otherwise specified, the terms "include" and "comprising" used in this application are open-ended. For example, "include" and "comprising" may mean that other components not listed may also be included or that only the listed components are included.

[0066] In this 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. Phrases containing this term, for example, "C1-C20 alkyl" refers to an alkyl group containing 1 to 10 carbon atoms, and each occurrence can independently be C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, C9 alkyl, C10 alkyl, C12 alkyl, C15 alkyl, or 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).

[0067] In this application, the term "hydrocarbyl" 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., alkyl) and the group remaining after an unsaturated alkane loses a hydrogen atom. The group remaining after an unsaturated alkane loses a hydrogen atom includes an alkenyl group.

[0068] 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 and A-site cations occupying vertex positions.

[0069] 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.

[0070] In one embodiment of the present application, a solar cell is provided, 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 the main chain atoms of the ionic polymer passivator are connected to at least one substituent R 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.

[0071] It is understood that the positively charged nitrogen heterocycle combines with the anion X to form a salt. The positively charged nitrogen heterocycle is equivalent to the cation in the salt.

[0072] It is understood that the perovskite light absorbing layer is a three-dimensional perovskite thin film. The perovskite material included in the perovskite light absorbing layer is a three-dimensional perovskite. The perovskite light absorbing layer can be prepared using methods commonly used in the art, including but not limited to sol-gel methods, coating, multi-source co-evaporation, and other methods. It is understood that coating methods include but are not limited to spin coating, slit coating, brush coating, wipe coating, doctor blade coating, screen coating, and spray coating.

[0073] 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.

[0074] 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 its ion migration and ion migration to the perovskite light absorption layer are reduced. The ionic polymer passivator has good electron conductivity and does not affect electron transmission when it is arranged on the side of the electron transport layer. Therefore, it can improve the photoelectric conversion efficiency and stability of the solar cell.

[0075] It is understood that the structure of each layer of the aforementioned solar cell can be directly revealed by scanning electron microscopy of a cross-section of the cell. The presence of the ionic polymer passivating agent having the aforementioned structure can be confirmed by sampling the interface passivation layer of the cross-section at specific points and performing at least one of infrared and mass spectrometry tests.

[0076] It is understood that the positively charged nitrogen heterocycle may contain other heteroatoms in addition to nitrogen heteroatoms, 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.

[0077] In some embodiments, the substituent R of the ionic polymer passivator 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.

[0078] It is understood that the five-membered nitrogen heterocycle and the six-membered nitrogen heterocycle can be aromatic heterocycles or non-aromatic heterocycles.

[0079] A fused ring means that there are at least two cyclic structures that share at least two ring atoms. A fused nitrogen heterocycle means that the atoms constituting the fused ring contain nitrogen heteroatoms in addition to carbon atoms.

[0080] Optionally, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 4, 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.

[0081] Optionally, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 4, 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).

[0082] 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. Furthermore, 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 idine, quinazoline, dibenzothiophene, phenazine and phenothiazine.

[0083] In some embodiments, the ring atoms in the positively charged nitrogen heterocycle are connected to the main chain atoms via a linker L, and L is a single bond or includes a C1-C10 alkyl group.

[0084] L is a single bond, i.e., a ring atom in the positively charged nitrogen heterocycle is directly connected to a main chain atom. It is understood that the ring atom in the positively charged nitrogen heterocycle can be a nitrogen atom or a non-nitrogen atom.

[0085] In other embodiments, L is not a single bond. 1 In the embodiment, the ring atoms in the positively charged nitrogen heterocycle are connected to the main chain atoms via a linker L, wherein L comprises 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. For example, the C1-C10 alkyl group can be (CH2)n-, where n is an integer between 1 and 10.

[0086] In some embodiments, the ionic polymer passivator includes a structural unit A, wherein the structural unit A is at least one H substituted with a group R 1 Substituted -CH2-CH2-, and R 1 The positively charged nitrogen heterocycle in the is bound to an anion X.

[0087] Furthermore, the structural unit A has any one of the following structures A1 to A10. Optionally, the ionic polymer passivator has multiple structural units A, and each of the multiple structural units A is 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.

[0088] In some embodiments, the backbone chain of the ionic polymer passivating agent is a carbon chain.

[0089] In some embodiments, the repeating unit of the ionic polymer passivator is structural unit A.

[0090] Furthermore, 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:

[0091] 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); 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, which can be purchased from Shanghai Zaofu Technology).

[0092] In some other embodiments, the ionic polymer passivator may further include a structural unit B, wherein the structural unit B has a carbon backbone and does not have a positively charged nitrogen heterocycle. Further, the structural unit B has a backbone -CH2-CH2-, and the H in the structural unit B is unsubstituted or at least one H is substituted with a substituent R 2 Replacement, R 2 It does not have a positively charged nitrogen heterocycle.

[0093] 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.

[0094] 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, or 0.8.

[0095] Further, as an example, L is a methylene group, and the structure of the ionic polymer passivator is shown in Formula 12 below:

[0096] Formula 12, n is the degree of polymerization.

[0097] In some embodiments, X comprises F - 、Cl - Br - , I - TFSI (bis(trifluoromethanesulfonyl imide) ion), SCN, OCN, organic acid ions, 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 .

[0098] Furthermore, the organic acid radical ions include at least one of carboxylate ions, sulfonate ions, sulfinate ions, thiolate ions, phosphonate ions and phosphinate ions. As an example, the carboxylate ions include but are not limited to CH3COO - and HCOO -At least one of .

[0099] In some 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.

[0100] In some 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 optionally 10nm to 50nm, 10nm to 30nm or 15nm to 25nm, or a range consisting of any two end values.

[0101] In some embodiments, the thickness of the perovskite light absorbing layer is 300 nm to 1000 nm. As an example, the thickness of the perovskite light absorbing layer is 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, or 1000 nm; optionally, 400 nm to 500 nm.

[0102] Furthermore, the perovskite material in the above-mentioned perovskite light absorption 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.

[0103] 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 formamidinium 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 methylamino (MA), ethylamino, propylamino, butylamino, pentylamino and hexylamino.

[0104] 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+ 、Cu 2+ and Ni2+ More preferably, the B ions include Pb 2+ and Sn 2+ One or both of them.

[0105] Optionally, the C ions include Cs + 、Ag + , K + Ru + At least one of .

[0106] Optionally, the D ions include Bi 3+ 、Ni 3+ 、Fe 3+ and Cu 3+ At least one of;

[0107] 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 .

[0108] It is 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.

[0109] 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.

[0110] 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), cuprous thiocyanate (CuSCN).

[0111] Optionally, the solar cell may further include a hole blocking layer between the first electrode layer and the electron transport layer.

[0112] The hole blocking layer material may include, but is not limited to, BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline).

[0113] 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.

[0114] It is understood that the solar cell may also generally include a hole transport layer between the second electrode layer and the perovskite light absorbing layer. Further, optionally, the solar cell may also include an electron blocking layer between the second electrode layer and the hole transport layer.

[0115] 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.

[0116] 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-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), polytriarylamine (PTAA), NiOx (nickel oxide), poly-3,4-ethylenedioxythiophene:polystyrene sulfonate (PEDOT:PSS), WO3, or one or more materials that can transport holes and block electrons. The electron blocking layer material may be a known material.

[0117] Understandably, 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.

[0118] It is understood that solar cells include a regular structure and a transverse 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.

[0119] For the formal structure, as an example, as shown in Figure 1, 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 stacked in sequence 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 provided between the perovskite light absorption layer and the electron transport layer.

[0120] For an inverted structure, as shown in FIG2 , 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 stacked sequentially on the transparent electrode 11. The second electrode layer is a transparent electrode, and the first electrode layer is a counter electrode layer.

[0121] 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 understood 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 a mixture of one or more of the following materials in different proportions: polyvinyl alcohol (PVA), polyester (PET), polyimide (PI), polyethylene naphthalate (PEN), and polydimethylsiloxane (PDMS).

[0122] As an example, the material of the counter electrode layer is, but is not limited to, an organic or inorganic conductive material, or a mixture of the two in varying proportions. As an example, the counter electrode layer is a metal electrode, such as a metal conductive material such as 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.

[0123] The present application also provides a method for preparing the above-mentioned solar cell, comprising the steps of forming the above-mentioned first electrode layer, the above-mentioned electron transport layer, the above-mentioned interface passivation layer, the above-mentioned perovskite light absorption layer and the above-mentioned second electrode layer in a stacked arrangement.

[0124] In some embodiments, the preparation method includes the following steps S11 to S14.

[0125] S11, forming a perovskite light absorption layer on the second electrode layer;

[0126] S12, forming an interface passivation layer on a surface of the perovskite light absorbing layer away from the second electrode layer;

[0127] S13, forming an electron transport layer on a surface of the interface passivation layer away from the perovskite light absorption layer.

[0128] S14, forming a first electrode layer on a surface of the electron transport layer away from the interface passivation layer.

[0129] Specifically, as an example, the solar cell is in the trans type, and the preparation method thereof includes the following steps:

[0130] Step 1: Etch and clean the transparent electrode and dry it;

[0131] Step 2: Prepare a hole transport layer on the transparent electrode;

[0132] Step 3: preparing a perovskite light absorption layer on the hole transport layer;

[0133] Step 4: preparing the above-mentioned interface passivation layer on the perovskite light absorption layer;

[0134] Step 5: preparing an electron transport layer on the interface passivation layer;

[0135] Step 5: Prepare a second electrode layer on the electron transport layer.

[0136] In some embodiments, the preparation method includes the following steps S21 to S23.

[0137] S21, forming a perovskite light absorption layer on the second electrode layer;

[0138] 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 to form a film of the slurry, thereby forming a stacked interface passivation layer and an electron transport layer on the perovskite light absorbing layer.

[0139] 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.

[0140] Furthermore, the slurry includes an ionic polymer passivator, an electron transport material and an organic solvent.

[0141] Furthermore, the electron transport material in the slurry may be at least one of PCBM, fullerene and derivatives thereof.

[0142] As an example, the organic solvent includes, but is not limited to, at least one of IPA (isopropyl alcohol) and THF (tetrahydrofuran).

[0143] Optionally, the mass ratio of the ionic polymer passivator to the electron transport material in the slurry is 1:100 to 1:10. For 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.

[0144] S23 , forming a first electrode layer on a surface of the electron transport layer away from the interface passivation layer.

[0145] 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 prepare a perovskite precursor solution; then coating the perovskite precursor solution on a corresponding substrate, annealing, and obtaining a perovskite light absorption layer.

[0146] The above-mentioned first electrode, hole transport layer, electron transport layer and second electrode can be prepared by commonly used preparation methods in the field, including but not limited to solution method and solid deposition method. The solution method includes any one of spin coating, spray coating, blade coating and slit coating, and the solid deposition method includes any one of vacuum evaporation, sputtering deposition, plasma deposition and ion deposition.

[0147] One embodiment of the present application further provides a photovoltaic module, which includes the above-mentioned solar cell.

[0148] The solar cell has high light conversion efficiency and good stability, and can improve the efficiency of photovoltaic modules.

[0149] 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.

[0150] In some embodiments, the photovoltaic module further includes a photovoltaic glass layer, a bonding layer, and a back sheet.

[0151] Adhesive layers are provided on both surfaces of the cell, a back plate is provided on the surface of one of the adhesive layers away from the cell, and a photovoltaic glass layer is provided on the surface of the other adhesive layer away from the cell.

[0152] The photovoltaic glass layer and back panel are used to protect the solar cells, and have the functions of sealing, insulation and waterproofing; the bonding layer plays the role of bonding the photovoltaic glass layer and the battery cell, and bonding the back panel and the battery cell.

[0153] 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).

[0154] Furthermore, the photovoltaic module further includes a junction box and an outer frame.

[0155] 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.

[0156] 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.

[0157] Furthermore, silicone is used to bond and seal the connection between the frame and other parts of the photovoltaic module. Photovoltaic modules can convert solar energy into electrical energy, which can be stored in batteries or used to drive loads.

[0158] In some embodiments, the photovoltaic component is a solar panel.

[0159] One embodiment of the present application further provides a photovoltaic system, comprising the above-mentioned photovoltaic module.

[0160] The photovoltaic system utilizes the photovoltaic effect of the solar cells in the above photovoltaic modules to directly convert solar radiation energy into electrical energy with high efficiency; further, the above photovoltaic system is a photovoltaic power generation system.

[0161] 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 the specific application scenario; further, when the above photovoltaic system includes multiple photovoltaic modules, the multiple photovoltaic modules form a photovoltaic array.

[0162] The above photovoltaic system can be an independent photovoltaic power generation system or a grid-connected photovoltaic power generation system.

[0163] An independent photovoltaic power generation system consists of a photovoltaic array, a battery pack, a charge controller, a power electronic converter (inverter), and a load. Its operating principle is that solar radiation energy is first converted into electrical energy by the photovoltaic array, then converted by the power electronic converter to power the load. Meanwhile, excess electrical energy is stored as chemical energy in an energy storage device after passing through the charge controller. In this way, when sunlight is insufficient, the energy stored in the battery can be converted into 220V, 50Hz AC electricity after passing through the power electronic inverter, filtering, and power frequency transformer to supply the AC load.

[0164] A grid-connected photovoltaic power generation system consists of a photovoltaic array, a high-frequency DC / DC boost circuit, a power electronic converter (inverter), and system monitoring. Its operating principle is that solar radiation energy is converted by the photovoltaic array, then converted to high-voltage DC through high-frequency DC conversion. This is then inverted by a power electronic inverter and output to the grid as a sinusoidal AC current with a frequency consistent with the grid voltage.

[0165] The above two photovoltaic power generation systems have their own characteristics and can be selected according to specific application scenarios.

[0166] One embodiment of the present application provides an electrical device, including the above-mentioned solar cell or the above-mentioned photovoltaic module.

[0167] In some embodiments, the solar cell or photovoltaic module can be used as a power source for an electrical device or as an energy storage unit for an electrical device.

[0168] Furthermore, the above-mentioned electrical devices may include mobile devices, such as mobile phones, laptop computers, etc., electric vehicles, electric trains, ships and satellites, but are not limited thereto.

[0169] Figure 3 shows an example of an electric device 2. The electric device 2 is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle.

[0170] In order to make the technical problems, technical solutions and beneficial effects solved by this application clearer, the application will be further described in detail below with reference to the embodiments and drawings. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its applications. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0171] If no specific techniques or conditions are specified in the examples, the experiments were carried out according to the techniques or conditions described in the literature in the field or according to the product instructions. All reagents or instruments used without specifying the manufacturer are commercially available conventional products.

[0172] 1. Device Preparation

[0173] Sources of raw materials: The passivating agents used in the examples and comparative examples were all commercially available.

[0174] The structures of the ionic polymer passivating agents are shown in the following formulas 1 to 10, wherein X is Cl.

[0175] 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); the abbreviations of the passivating agents of Formulas 6 to 10 are P2VP-OH (Formula 6, CAS: 9046-50-8), P2VP-X (Formula 7), P4VP-X (Formula 8), P4VP-OH (Formula 9, CAS: 26715-00-4), and PVDABCO-X (Formula 10, available from Shanghai Zaofu Technology).

[0176] The repeating unit of the passivating agent in Example 16 is shown in Formula 11 below, 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.

[0177] n is 0.5.

[0178] 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.

[0179] Formulas 1-5, 7-8, and 10-12 can also be obtained by purifying the corresponding amines by mixing and purifying with hydrochloric acid. The specific preparation is as follows: Dissolve the corresponding amine (1 g) in 30 mL of tetrahydrofuran, slowly add concentrated hydrochloric acid (1 mL) dropwise in an ice-water bath. Stir for 6 hours, then pour into 100 mL of diethyl ether. Collect the precipitate and dry it to obtain the corresponding hydrochloride.

[0180] The CAS number of the amine corresponding to formula 1 is 25232-42-2, the CAS number of the amine corresponding to formula 7 is 25014-15-7, the CAS number of the amine corresponding to formula 8 is 25232-41-1, and the CAS number of the amine corresponding to formula 11 is 26222-40-2.

[0181] Furthermore, the amines corresponding to Formula 2-5, Formula 10, and Formula 12 are obtained by polymerizing the corresponding monomers by conventional solution polymerization, such as reacting in a muffle furnace at a reaction temperature of 140° C. and a pressure of 5 MPa for 6 hours to obtain the corresponding amines.

[0182] The CAS number of the monomer corresponding to formula 2 is 71580-34-2, the CAS number of the monomer corresponding to formula 3 is 52355-95-0, the CAS number of the monomer corresponding to formula 4 is 7613-15-2, the CAS number of the monomer corresponding to formula 5 is 45590-53-2, and the CAS number of the monomer corresponding to formula 12 is 80880-49-5.

[0183] Example 1

[0184] As shown in FIG4 , a method for preparing a solar cell device with an inverted structure is as follows:

[0185] An oxide film with a thickness of 30 nm was formed on the ITO glass by magnetron sputtering as a nickel hole transport layer.

[0186] A 1.4 mol / L perovskite precursor solution (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.

[0187] An ionic polymer passivator solution (1 mg / mL, in isopropyl alcohol) was spin-coated on the perovskite film at 3000 rpm. After the passivator formed a film, an interfacial passivation layer was formed on the perovskite surface. The specific type of ionic polymer passivator and the thickness of the interfacial passivation layer are shown in Table 1.

[0188] A C60 layer (graphene layer) with a thickness of 30 nm was formed on the interface passivation layer by thermal evaporation as an electron transport layer.

[0189] A 5 nm thick BCP layer was formed on the electron transport layer by thermal evaporation as a hole blocking layer. In FIG4 , the stack of the C60 layer and the BCP layer is represented by C60 / BCP.

[0190] A copper electrode with a thickness of 100 nm was formed on the hole blocking layer by thermal evaporation.

[0191] Example 2

[0192] As shown in FIG5 , a method for preparing a solar cell device with an inverted structure is as follows:

[0193] A nickel oxide hole transport layer with a thickness of 30 nm was formed on the ITO glass by magnetron sputtering.

[0194] A 1.4 mol / L perovskite precursor solution (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.

[0195] A mixed solution of PCBM and an ionic polymer passivator (solvent: THF / isopropanol, concentrations of 10 mg / mL PCBM and 0.1 mg / mL ionic polymer passivator, represented as "PCBM mix" in Figure 5) was spin-coated on the perovskite film at 5000 rpm. This formed an interfacial passivation layer (component: the ionic polymer passivator) on the perovskite surface. A PCBM layer approximately 30 nm thick was formed on top of the interfacial passivation layer, serving as an electron transport layer. The specific types of ionic polymer passivators and the thickness of the interfacial passivation layer are shown in Table 1.

[0196] A copper electrode with a thickness of 100 nm was formed on the electron transport layer by thermal evaporation.

[0197] Examples 1 to 17

[0198] It is basically the same as Example 1 or Example 2 (see "Similar Structure" in Table 1 for details), except that the ionic polymer passivator in Example 1 is replaced by another type of ionic polymer passivator of equal mass, as shown in Table 1.

[0199] Examples 18-19

[0200] Compared with Example 8, the only difference is the thickness of the controlled interface passivation layer (controlled by controlling the amount of the spin-coated ionic polymer passivator solution).

[0201] Comparative Example 1

[0202] It is basically the same as Example 1, except that the interface passivation layer in Example 1 is omitted.

[0203] Comparative Example 2

[0204] 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.

[0205] As shown in FIG6 , a method for preparing a solar cell device with a formal structure is as follows:

[0206] A 30 nm thick tin oxide film was formed on the ITO glass by magnetron sputtering as an electron transport layer.

[0207] 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. The components of the perovskite film are Cs 0.05 FA 0.90 MA 0.05 PbI3.

[0208] An ionic polymer passivator solution (1 mg / mL, in isopropyl alcohol) was spin-coated on the perovskite film at 3000 rpm. After the passivator formed a film, an interfacial passivation layer was formed on the perovskite surface. The specific type of ionic polymer passivator and the thickness of the interfacial passivation layer are shown in Table 1.

[0209] A Spiro-OMeTAD layer with a thickness of 80 nm was formed on the interfacial passivation layer by blade coating as a hole transport layer.

[0210] A gold electrode with a thickness of 100 nm was formed on the hole transport layer by thermal evaporation.

[0211] Comparative Example 3

[0212] The process 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 monomer salt 1 of equal mass.

[0213] Comparative Example 4

[0214] The process 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 monomer salt 2 of equal mass.

[0215] The structures of monomer salt 1 (CAS: 3287-99-8) and monomer salt 2 (CAS: 628-13-7) are as follows:

[0216] Comparative Example 5

[0217] 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.

[0218] 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.

[0219] Comparative Example 6

[0220] 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.

[0221] 2. Performance Testing

[0222] 1) IV performance test to obtain open circuit voltage and initial efficiency

[0223] Specific steps: Store the obtained battery away from light. The test of solar cells (IV test) uses a solar simulator of Guangyan, which complies with the national standard IEC61215. The light intensity is calibrated using a crystalline silicon solar cell 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.

[0224] 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 (V), maximum optical output current Jmpp (mA), and maximum optical output voltage Vmpp (V). The cell's fill factor (FF) (in %) is calculated using the formula FF = Jsc × Voc / (Jmpp × Vmpp). The cell's photoelectric conversion efficiency (PCE) (i.e., initial efficiency) is calculated using the formula PCE = Jsc × Voc × FF / Pw (in %), where Pw represents the input power (in mW).

[0225] The initial efficiency results are shown in Table 1.

[0226] 2) Efficiency change rate after 72 hours of maximum power light aging

[0227] The conditions for 72 hours of maximum power light aging are as follows:

[0228] Efficiency change rate = (efficiency after 72 hours of maximum power light aging - initial efficiency before aging) * 100% / initial efficiency before aging. The efficiency after 72 hours of maximum power light aging was tested using the same method as the initial efficiency. The results are shown in Table 1.

[0229] Table 1

[0230] 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.

[0231] Comparative Example 1 did not use a passivator to passivate the perovskite film. Comparative Examples 3 and 4 used monomeric salts as passivators. Their efficiency change rates after 72 hours of maximum power light aging were much lower, indicating that their passivation effect was 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.

[0232] Comparative Examples 5 to 6 all use other types of passivators. The results show that although the passivator of Comparative Example 5 can improve the stability of device efficiency, its effect on improving the initial efficiency of the solar cell device is small; the passivator of Comparative Example 6 does not improve the initial efficiency and stability of the solar cell device, but instead reduces them.

[0233] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any other embodiments that can be conceived by those skilled in the art and that combine some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. 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 arranged in a stacked manner; 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 further includes an anion X combined with the positively charged nitrogen heterocycle.

2. The solar cell according to claim 1, wherein: 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.

3. The solar cell according to claim 2, wherein: The number of nitrogen ring atoms in the five-membered nitrogen heterocyclic ring is 1-4.

4. The solar cell according to claim 3, wherein: The number of nitrogen ring atoms in the five-membered nitrogen heterocyclic ring is 1 to 3.

5. The solar cell according to claim 2, wherein: The five-membered nitrogen heterocycle includes at least one of pyrrole, pyrazole, imidazole, oxazole, thiazole and triazole.

6. The solar cell according to any one of claims 2 to 5, wherein: The number of nitrogen ring atoms in the six-membered nitrogen heterocyclic ring is 1-4.

7. The solar cell according to claim 6, wherein: The number of nitrogen ring atoms in the six-membered nitrogen heterocyclic ring is 1 to 3.

8. The solar cell according to claim 6, wherein: The six-membered nitrogen heterocycle includes at least one of pyridine, pyrimidine, monoazacyclohexane, pyridazine, pyrazine and piperazine.

9. The solar cell according to any one of claims 2 to 8, wherein: The condensed nitrogen heterocycle includes at least one of the five-membered nitrogen heterocycle and the six-membered nitrogen heterocycle.

10. The solar cell according to claim 9, wherein: The fused nitrogen heterocycle includes at least one of indole, carbazole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, thienothiophene, furopyrrole, thienofuran, benzisoxazole, benzisothiazole, benzimidazole, quinoline, isoquinoline, 2,3-diazine, quinoxaline, phenanthridine, primary dine, quinazoline, dibenzothiophene, phenazine and phenothiazine.

11. The solar cell according to any one of claims 1 to 10, wherein: 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.

12. The solar cell according to any one of claims 1 to 11, wherein: 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.

13. The solar cell according to claim 12, wherein: The structural unit A has any one of the following structures A1 to A10, and L is a single bond or includes a C1-C10 alkyl group.

14. The solar cell according to claim 13, wherein: There are multiple structural units A in the ionic polymer passivator, and each of the multiple structural units A is independently selected from any one of the following structures A1 to A10; 15. The solar cell according to any one of claims 12 to 14, wherein: The repeating unit of the ionic polymer passivator is the structural unit A. 16 . The solar cell according to claim 12 , wherein 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.

17. The solar cell according to claim 16, wherein: 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 by a substituent R 2 Replacement, R 2 It does not have a positively charged nitrogen heterocycle.

18. The solar cell according to claim 17, wherein: R 2 It includes at least one of a five-membered ring, a six-membered ring and a condensed ring.

19. The solar cell according to any one of claims 1 to 18, wherein: X includes F - , Cl - Br - ,I - , TFSI, SCN, OCN, organic acid radical ions, OH - 、BF4 - and PF6 - Any one of .

20. The solar cell according to claim 19, wherein There are multiple X in the ionic polymer passivator, and each of the multiple X independently includes F - , Cl - Br - ,I - , TFSI, SCN, OCN, organic acid radical ions, OH - 、BF4 - and PF6 - Any one of .

21. The solar cell according to any one of claims 1 to 20, wherein: The solar cell satisfies at least one of the following characteristics: (1) The thickness of the interface passivation layer is 5 nm to 80 nm; (2) The weight average molecular weight of the ionic polymer passivator is 10,000 to 200,000; (3) The thickness of the perovskite light absorbing layer is 300nm to 1000nm.

22. The solar cell according to claim 21, wherein: The solar cell satisfies at least one of the following characteristics: (1) The thickness of the interface passivation layer is 10 nm to 30 nm; (2) The weight average molecular weight of the ionic polymer passivator is 10,000 to 100,000; (3) The thickness of the perovskite light absorbing layer is 400nm to 500nm.

23. A method for preparing the solar cell according to any one of claims 1 to 22, comprising the step 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.

24. The method for preparing a solar cell according to claim 23, wherein: 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.

25. The method for preparing a solar cell according to claim 23, wherein: 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.

26. A photovoltaic module comprising the solar cell according to any one of claims 1 to 22.

27. A photovoltaic system comprising the photovoltaic module according to claim 26.

28. An electrical device comprising at least one selected from the solar cell according to any one of claims 1 to 22 and the photovoltaic module according to claim 26.

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