Perovskite solar cell and preparation method and application thereof

Abstract

The invention relates to the technical field of solar cells, in particular to a perovskite solar cell and a preparation method and application thereof. The perovskite solar cell comprises a first electrode, a perovskite layer, a passivation layer, an electron transport layer and a second electrode which are sequentially stacked, the passivation layer comprises a nitrogen heterocyclic halide, and H on a nitrogen heterocyclic ring of the nitrogen heterocyclic halide is not substituted or at least one H is substituted by a substituent group. The passivation layer is arranged between the perovskite layer and the electron transport layer, so that the open-circuit voltage and the photoelectric conversion efficiency of the perovskite solar cell can be improved.

Description

Technical Field

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

[0002] Perovskite materials refer to organic and inorganic metal halides ABX3 with a crystal structure similar to perovskite (CaTiO3). Solar cells prepared with perovskite materials as photosensitive layers have the advantages of low cost and high energy conversion efficiency. However, there are serious interface defects at the interface between the perovskite layer formed by the perovskite material and the electron transport layer. This defect can cause serious recombination between the holes on the surface of the perovskite material and the electrons extracted by the electron transport layer, resulting in open circuit voltage loss of solar cell devices and affecting device efficiency. Summary of the invention

[0003] Based on this, it is necessary to provide a perovskite solar cell and a preparation method and application thereof that can improve the open circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0004] In a first aspect of the present application, a perovskite solar cell is provided, comprising a first electrode, a perovskite layer, a passivation layer, an electron transport layer and a second electrode stacked in sequence, wherein the passivation layer comprises a nitrogen heterocyclic halide, wherein the H on the nitrogen heterocyclic ring of the nitrogen heterocyclic halide is unsubstituted or at least one H is substituted by a substituent.

[0005] In the above-mentioned perovskite solar cell, the passivation layer can not only passivate the surface defects of the perovskite layer, but also passivate the defects between the perovskite layer and the electron transport layer, reduce non-radiative recombination losses, and thus improve the open circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0006] In some embodiments, the substituent is located at the nitrogen ring atom of the nitrogen heterocycle or at the ortho-para position thereof.

[0007] In some embodiments, the nitrogen heterocycle includes at least one of a five-membered nitrogen heterocycle, a six-membered nitrogen heterocycle, and a condensed nitrogen heterocycle.

[0008] In some embodiments, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 4, and more optionally 1 to 3; more optionally, the five-membered nitrogen heterocycle includes at least one of pyrrole, pyrazole, imidazole and thiazole.

[0009] In some embodiments, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 4, and more optionally 1 to 3; more optionally, the six-membered nitrogen heterocycle includes at least one of pyridine, piperidine, pyrimidine, morpholine, thiomorpholine, monoazacyclohexane, pyrazine and piperazine.

[0010] In some embodiments, 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 purine, indole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, furanopyrrole, benzisothiazole, benzimidazole, quinoline, isoquinoline, quinoxaline and quinazoline.

[0011] In some embodiments, the substituent includes -N-R2HX, R includes any one of H, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl and substituted or unsubstituted heterocyclic, and multiple Xs each independently include Cl - Br - ,I - .

[0012] In some embodiments, the alkyl group includes a C1 to C8 alkyl group.

[0013] In some embodiments, the cycloalkyl group includes C3-C8 cycloalkyl groups.

[0014] In some embodiments, the heterocyclic group includes a C4-C8 heterocyclic group.

[0015] In some embodiments, the nitrogen heterocyclic halide comprises at least one of Formula 1 to Formula 9:

[0016]

[0017] In Formulae 1 to 9, the plurality of Xs each independently include Cl, Br, and I.

[0018] In some embodiments, the thickness of the passivation layer is less than 10 nm, and can be optionally 0.1 nm to 5 nm.

[0019] The second aspect of the present application provides a method for preparing a perovskite solar cell as described in the first aspect of the present application, comprising the steps of forming the first electrode, the perovskite layer, the passivation layer, the electron transport layer and the second electrode.

[0020] The third aspect of the present application provides a photovoltaic module, comprising the perovskite solar cell described in the first aspect of the present application or the perovskite solar cell prepared by the preparation method described in the second aspect of the present application.

[0021] The above photovoltaic module has at least the same advantages as the perovskite solar cell described in the first aspect of the present application.

[0022] A fourth aspect of the present application provides a photovoltaic system, comprising the photovoltaic component described in the third aspect of the present application.

[0023] The above photovoltaic system has at least the same advantages as the perovskite solar cell described in the first aspect of the present application.

[0024] In a fifth aspect of the present application, an electrical device is provided, comprising the perovskite solar cell described in the first aspect of the present application or the perovskite solar cell prepared by the preparation method described in the second aspect of the present application.

[0025] The above-mentioned electrical device has at least the same advantages as the perovskite solar cell described in the first aspect of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of a perovskite solar cell according to one embodiment of the present application.

[0027] Figure 2 Schematic diagram of a perovskite solar cell according to another embodiment of the present application.

[0028] Figure 3 A schematic diagram of an electrical device using a perovskite solar cell as a power source according to an embodiment of the present application.

[0029] Description of reference numerals:

[0030] 1. Perovskite solar cell; 11. Transparent electrode; 12. Electron transport layer; 13. Passivation layer; 14. Perovskite layer; 15. Hole transport layer; 16. Counter electrode; 20. Electrical device. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0032] "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.

[0033] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0034] 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.

[0035] 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.

[0036] If there is no special explanation, the "include" and "comprising" mentioned in this application represent open-ended or closed-ended expressions. For example, the "include" and "comprising" may represent that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0037] If not specifically stated, in this application, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0040] In the present application, the term "alkyl" refers to a saturated hydrocarbon containing a primary (normal) carbon atom, or a secondary carbon atom, or a tertiary carbon atom, or a quaternary carbon atom, or a combination thereof. A phrase containing the term, for example, "C1-C9 alkyl" refers to an alkyl containing 1 to 9 carbon atoms, and each occurrence may be independently C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl or C9 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).

[0041] In the present application, the term "cycloalkyl" refers to a non-aromatic hydrocarbon containing ring carbon atoms, which can be a monocyclic alkyl, a spirocyclic alkyl, or a bridged cycloalkyl. Phrases containing this term, for example, "C3-C9 cycloalkyl" refers to a cycloalkyl containing 3 to 9 carbon atoms, each occurrence of which can be independently C3 cycloalkyl, C4 cycloalkyl, C5 cycloalkyl, C6 cycloalkyl, C7 cycloalkyl, C8 cycloalkyl or C9 cycloalkyl. Suitable examples include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and cycloheptyl. In addition, "cycloalkyl" may also contain one or more double bonds, and representative examples of cycloalkyl containing double bonds include cyclopentenyl, cyclohexenyl, cyclohexadienyl and cyclobutadienyl.

[0042] In the present application, "heterocyclyl" means that at least one carbon atom is replaced by a non-carbon atom on the basis of a cycloalkyl group, and the non-carbon atom can be an N atom, an O atom, an S atom, etc., and can be a saturated ring or a partially unsaturated ring. Phrases containing this term, for example, "C4-C9 heterocyclyl" means a heterocyclyl group containing 4 to 9 carbon atoms, each occurrence of which can be independently C4 heteroalkyl, C6 heteroalkyl, C7 heteroalkyl, C8 heteroalkyl or C9 heteroalkyl. Suitable examples include, but are not limited to: dihydropyridyl, tetrahydropyridyl (piperidyl), tetrahydrothienyl, sulfur-oxidized tetrahydrothienyl, tetrahydrofuranyl, tetrahydroquinolyl, tetrahydroisoquinolyl, dihydroindole.

[0043] Traditional passivation materials mainly passivate the upper and lower surfaces of the perovskite layer itself. Although the upper and lower surface defects of the perovskite layer can be reduced and non-radiative recombination can be reduced, there are still serious interface defects at the interface between the perovskite layer and the electron transport layer. The defects can cause serious recombination between the holes on the surface of the perovskite and the electrons extracted by the electron transport layer, resulting in a loss of open circuit voltage of the solar cell and a reduction in device efficiency. Based on this, the present application provides a perovskite solar cell, which includes a first electrode, a perovskite layer, a passivation layer, an electron transport layer and a second electrode stacked in sequence, the passivation layer includes a nitrogen heterocyclic halide, and the H on the nitrogen heterocyclic of the nitrogen heterocyclic halide is not substituted or at least one H is substituted by a substituent; the above-mentioned passivation layer can not only passivate the surface defects of the perovskite layer, but also passivate the defects between the perovskite layer and the electron transport layer, reduce non-radiative recombination losses, thereby improving the open circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0044] An embodiment of the present application provides a perovskite solar cell, comprising a first electrode, a perovskite layer, a passivation layer, an electron transport layer and a second electrode stacked in sequence, the passivation layer comprising a nitrogen heterocyclic halide, the H on the nitrogen heterocyclic ring of the nitrogen heterocyclic halide is unsubstituted or at least one H is substituted by a substituent.

[0045] The main chain structure of the above-mentioned nitrogen heterocyclic halide has a certain steric hindrance effect, high polarity, and does not react with the perovskite layer and the passivation layer. In addition, the above-mentioned nitrogen heterocyclic halide can adjust the energy band structure. It is located between the perovskite layer and the electron transport layer, inhibiting the charge recombination at the interface and reducing the non-radiative recombination loss, thereby improving the open circuit voltage and photoelectric conversion efficiency of the perovskite solar cell.

[0046] In some embodiments, the substituent is located at the nitrogen ring atom of the nitrogen heterocycle or at its ortho-para position. It should be noted that the substituent can be connected to the nitrogen ring atom on the nitrogen heterocycle, or it can be connected to the adjacent position or relative position of the nitrogen ring atom on the nitrogen heterocycle. In this application, "the adjacent position of the nitrogen ring atom on the nitrogen heterocycle" refers to the position adjacent to the nitrogen atom on the nitrogen heterocycle; "the relative position of the nitrogen ring atom on the nitrogen heterocycle" refers to the position on the nitrogen heterocycle that is two positions away from the nitrogen atom on the nitrogen heterocycle.

[0047] In some embodiments, the nitrogen heterocycle includes at least one of a five-membered nitrogen heterocycle, a six-membered nitrogen heterocycle and a fused nitrogen heterocycle. It is understood that the five-membered nitrogen heterocycle and the six-membered nitrogen heterocycle can be aromatic heterocycles or non-aromatic heterocycles. A fused nitrogen heterocycle refers to a polycyclic organic compound formed by two or more carbon rings or heterocycles. The atoms constituting the fused nitrogen heterocycle contain nitrogen heteroatoms in addition to carbon atoms, and may also contain other non-carbon atoms, such as oxygen heteroatoms, sulfur heteroatoms, etc.

[0048] In some embodiments, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 4. It is understood that the number of nitrogen ring atoms in the five-membered nitrogen heterocycle includes but is not limited to: 1, 2, 3, 4. Optionally, the number of nitrogen ring atoms in the five-membered nitrogen heterocycle is 1 to 3.

[0049] In some embodiments, the five-membered nitrogen heterocycle includes at least one of pyrrole, pyrazole, imidazole, and thiazole.

[0050] In some embodiments, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 4. It is understood that the number of nitrogen ring atoms in the six-membered nitrogen heterocycle includes but is not limited to: 1, 2, 3, 4. Optionally, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 3.

[0051] In some embodiments, the six-membered nitrogen heterocycle includes at least one of pyridine, piperidine, pyrimidine, morpholine, thiomorpholine, monoazacyclohexane, pyrazine, and piperazine.

[0052] In some embodiments, the fused nitrogen heterocycle includes at least one of a five-membered nitrogen heterocycle and a six-membered nitrogen heterocycle.

[0053] In some alternative embodiments, the fused nitrogen heterocycle includes at least one of purine, indole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, furanopyrrole, benzisothiazole, benzimidazole, quinoline, isoquinoline, quinoxaline and quinazoline.

[0054] In some embodiments, the substituent includes -N-R2HX, R includes any one of H, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl and substituted or unsubstituted heterocyclic, and multiple Xs each independently include Cl - Br - ,I - .

[0055] In some optional embodiments, the alkyl group includes a C1-C8 alkyl group.

[0056] In some optional embodiments, the cycloalkyl group includes C3-C8 cycloalkyl groups.

[0057] In some optional embodiments, the heterocyclic group includes a C4-C8 heterocyclic group.

[0058] In some embodiments, the nitrogen heterocyclic halide comprises at least one of Formula 1 to Formula 9:

[0059]

[0060] In Formulae 1 to 9, the plurality of Xs each independently include Cl, Br, and I.

[0061] In some embodiments, the thickness of the passivation layer is less than 10 nm. It is understood that the thickness of the passivation layer includes but is not limited to 0.1 nm, 0.5 nm, 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm. Optionally, the thickness of the passivation layer is 0.1 nm to 5 nm.

[0062] In some embodiments, the perovskite material in the perovskite 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.

[0063] In some embodiments, the A ions include at least one of an organic cation and a metal cation.

[0064] In some embodiments, the organic cation includes at least one of an organic amine ion, a formamidinium group (FA) and an imidazole group. Alternatively, the organic amine ion includes at least one of a methylamine group (MA), an ethylamine group, a propylamine group, a butylamine group, a pentylamine group and a hexylamine group.

[0065] In some embodiments, the metal cation comprises Li + 、Na + , K + , Rb + and Cs + At least one of .

[0066] In some embodiments, 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 Ni 2+ Optionally, the B ions include Pb 2+ and Sn 2+ At least one of .

[0067] In some embodiments, the C ions include Cs + 、Ag + , K + And Ru + At least one of .

[0068] In some embodiments, the D ions include Bi 3+ 、Ni 3+ , Fe 3+ and Cu 3+ At least one of .

[0069] In some embodiments, the X ions include F - , Cl - Br - and I - Optionally, the X ions include Cl - Br - and I - At least one of .

[0070] In some specific embodiments, the general formula of the perovskite material in the perovskite optical layer is Cs a FA b MA c Pb d X3, wherein a=0-0.05, b=0.8-0.95, c=0-0.1, a+b+c=1, d=1, X is selected from F - , Cl - Br -and I - At least one of .

[0071] In some embodiments, the electron transport layer material 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), triphenylamine (H101) with triptycene as the core, 3,4 -Ethylene dioxythiophene-methoxytriphenylamine (EDOT-OMeTPA), N-(4-aniline)carbazole-spirobifluorene (CzPAF-SBF), polythiophene, metal oxide (metal element is 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), BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline).

[0072] In some embodiments, the perovskite solar cell further includes a hole transport layer disposed between the first electrode and the perovskite layer. As an example, the hole transport layer material includes, 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, M2P (phosphoric acid carbazole salt), etc., which can transport holes and block electrons.

[0073] In some embodiments, one of the “first electrode” and the “second electrode” is a transparent electrode for light incidence.

[0074] In some embodiments, the material of the transparent electrode may be exemplified by, but not limited to, one or more of the following materials: FTO (fluorine-doped tin oxide), ITO (tin-doped indium oxide), AZO (aluminum-doped zinc oxide), BZO (boron-doped zinc oxide), IZO (indium zinc oxide), IWO (tungsten-doped indium oxide), etc.

[0075] In some embodiments, the second electrode comprises a conductive material, and further, the conductive material may be an organic conductive material, an inorganic conductive material, or a combination thereof. Non-limiting examples of inorganic conductive materials include metal conductive materials, and further, the metal conductive material may include any one of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), bismuth (Bi), platinum (Pt), magnesium (Mg), etc., or any suitable mixture of the aforementioned elements. The conductive material may include a conductive oxide, and further, the conductive material may be a conductive oxide; non-limiting examples of conductive oxides may include one or more of FTO, ITO, IWO, AZO, etc.

[0076] The perovskite solar cell provided in the present application may include a formal structure and a trans structure.

[0077] For a formal structure, as an example, Figure 1 As shown, the perovskite solar cell includes a transparent electrode 11 and an electron transport layer 12, a passivation layer 13, a perovskite layer 14, a hole transport layer 15 and a counter electrode 16 stacked sequentially on the transparent electrode 11. Among them, the transparent electrode 11 is a first electrode, the counter electrode 16 is a second electrode, and the passivation layer 13 is arranged between the perovskite layer 14 and the electron transport layer 12.

[0078] For the trans structure, as an example, Figure 2 As shown, the perovskite solar cell includes a transparent electrode 11 and a hole transport layer 15, a perovskite layer 14, a passivation layer 13, an electron transport layer 12 and a counter electrode 16 stacked sequentially on the transparent electrode 11. Among them, the transparent electrode 11 is the second electrode, the counter electrode 16 is the first electrode, and the passivation layer 13 is arranged between the perovskite layer 14 and the electron transport layer 12.

[0079] 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).

[0080] As an example, the material of the counter electrode 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 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 is a transparent conductive metal oxide electrode, such as FTO, ITO, aluminum-doped zinc oxide AZO, etc.

[0081] Another embodiment of the present application provides a method for preparing the above-mentioned perovskite solar cell, including the steps of forming a first electrode, a perovskite layer, a passivation layer, an electron transport layer and a second electrode.

[0082] In some embodiments, a method for preparing a perovskite solar cell comprises the following steps:

[0083] forming an electron transport layer on a surface of the first electrode;

[0084] forming a passivation layer on a surface of the electron transport layer away from the first electrode;

[0085] Forming a perovskite layer on a surface of the passivation layer away from the electron transport layer;

[0086] forming a hole transport layer on a surface of the perovskite layer away from the passivation layer;

[0087] A second electrode is formed on a surface of the hole transport layer away from the perovskite layer.

[0088] In some embodiments, the step of forming a perovskite layer on the surface of the passivation layer away from the electron transport layer includes: mixing a perovskite material with a solvent to obtain a perovskite precursor solution, spin coating the perovskite precursor solution on the electron transport layer, and annealing to obtain the perovskite layer. Optionally, the perovskite material includes a general formula of Cs a FA b MA c Pb d The perovskite material of X3, wherein a=0-0.05, b=0.8-0.95, c=0-0.1, a+b+c=1, d=1, and X is selected from F - , Cl - Br - and I - Further, the perovskite precursor solution has a general formula of Cs a FA b MA c Pb d The concentration of the perovskite material of X3 is 1M to 1.8M.

[0089] In some embodiments, the step of forming a passivation layer on the surface of the electron transport layer away from the first electrode includes: mixing a nitrogen heterocyclic halide with a solvent to obtain a passivator solution, spin-coating the passivator solvent on the electron transport layer, and annealing to obtain a passivation layer. Optionally, the concentration of the nitrogen heterocyclic halide in the passivator solution is 0.01 to 3 mg / mL. More optionally, the concentration of the nitrogen heterocyclic halide in the passivator solution is 0.05 to 1 mg / mL.

[0090] In some other embodiments, the method for preparing a perovskite solar cell comprises the following steps:

[0091] forming a hole transport layer on a surface of the first electrode;

[0092] forming a perovskite layer on a surface of the hole transport layer away from the first electrode;

[0093] forming a passivation layer on a surface of the perovskite layer away from the hole transport layer;

[0094] forming an electron transport layer on a surface of the passivation layer away from the perovskite layer;

[0095] A second electrode is formed on a surface of the electron transport layer away from the passivation layer.

[0096] In some embodiments, the step of forming a perovskite layer on the surface of the hole transport layer away from the first electrode includes: mixing a perovskite material with a solvent to obtain a perovskite precursor solution, spin coating the perovskite precursor solution on the hole transport layer, and annealing to obtain the perovskite layer. Optionally, the perovskite material includes a general formula of Cs a FA b MA c Pb d The perovskite material of X3, wherein a=0-0.05, b=0.8-0.95, c=0-0.1, a+b+c=1, d=1, and X is selected from F - , Cl - Br - and I - Further, the perovskite precursor solution has a general formula of Cs a FA b MA c Pb d The concentration of the perovskite material of X3 is 1M to 1.8M.

[0097] In some embodiments, the step of forming a passivation layer on the surface of the perovskite layer away from the hole transport layer includes: mixing a nitrogen heterocyclic halide with a solvent to obtain a passivator solution, spin-coating the passivator solvent on the perovskite layer, annealing and cooling, spin-coating a separate solvent on the obtained substrate, annealing, and obtaining a passivation layer. Optionally, the concentration of the nitrogen heterocyclic halide in the passivator solution is 0.01 to 3 mg / mL. More optionally, the concentration of the nitrogen heterocyclic halide in the passivator solution is 0.05 to 1 mg / mL.

[0098] It is understood that the first electrode, the hole transport layer, the electron transport layer and the second electrode can be prepared by a common preparation method in the art, and the above preparation method includes but is not limited to a solution method and a solid deposition method. Optionally, 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.

[0099] Yet another embodiment of the present application provides a photovoltaic module, comprising the above-mentioned perovskite solar cell or the perovskite solar cell prepared by the above-mentioned preparation method.

[0100] The above-mentioned photovoltaic module includes one or more perovskite solar cells, which can be selected according to the specific application scenario; further, the above-mentioned photovoltaic module includes multiple perovskite solar cells, and the multiple perovskite solar cells are connected in series or in parallel to form a battery cell.

[0101] In some embodiments, the photovoltaic module further includes a photovoltaic glass layer, a bonding layer and a back sheet.

[0102] 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.

[0103] 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.

[0104] 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).

[0105] Furthermore, the above photovoltaic assembly also includes a junction box and an outer frame.

[0106] 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.

[0107] 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.

[0108] 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.

[0109] In some embodiments, the photovoltaic module is a perovskite solar panel.

[0110] Yet another embodiment of the present application provides a photovoltaic system, comprising the above-mentioned photovoltaic assembly.

[0111] The photovoltaic system utilizes the photovoltaic effect of the perovskite solar cells in the above photovoltaic modules to directly convert solar radiation energy into electrical energy; further, the above photovoltaic system is a photovoltaic power generation system.

[0112] 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.

[0113] The above photovoltaic system can be an independent photovoltaic power generation system or a grid-connected photovoltaic power generation system.

[0114] 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.

[0115] 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.

[0116] The above two photovoltaic power generation systems have their own characteristics and can be selected according to specific application scenarios.

[0117] Another embodiment of the present application further provides an electrical device, comprising the above-mentioned perovskite solar cell or the perovskite solar cell prepared by the above-mentioned preparation method.

[0118] In some embodiments, the perovskite cell or the perovskite solar cell prepared by the preparation method can be used as a power generation device of an electrical device. The type of power generation device can include but is not limited to integrated power generation. The location of the power generation device can include but is not limited to the roof, back panel, etc. of a car.

[0119] Furthermore, the above-mentioned electrical devices may include mobile devices, such as mobile phones, laptop computers, etc., electric vehicles, electric trains, ships and satellites, power generation systems, etc., but are not limited thereto.

[0120] Figure 3 The power consumption device 20 is an automobile, and can further be a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle.

[0121] As another example, the electric device may be a mobile phone, a tablet computer, a laptop computer, a calculator, etc.

[0122] As another example, the power-consuming device may be a wearable device, such as a watch.

[0123] Hereinafter, the embodiments of the present application will be described. The embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If no specific techniques or conditions are indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be obtained commercially.

[0124] Example 1

[0125] (1) Preparation method of passivation material: Add 500 mg ND (4-aminopiperidine) to a clean round-bottom flask and add a magnet. According to the molar ratio of ND:HI=1:1.5, use a syringe to take HI aqueous solution and add it drop by drop into the round-bottom flask. Stir for 2 hours. At this time, a white precipitate is precipitated. Use vacuum filtration to obtain a white powder. Rinse the powder with ethyl acetate 3 times to obtain a pure product. Place the product in a vacuum oven at 30°C for 2 hours, take it out, and transfer it to a glove box for use.

[0126] (2) Method for confirming the passivation material: The NMR image of the material prepared in step (1) is obtained by testing, wherein 1HNMR (400 MHz, D2O) δ8.31 (s, 3H), 7.15 (s, 2H), 3.38-3.26 (m, 5H), 2.83-2.58 (m, 4H), indicating that the passivation material prepared in step (1) is 4-aminopiperidinium dihydroiodide (NDI).

[0127] (3) The preparation method of the solar cell device with an inverted structure is as follows:

[0128] A NiOx solution with a concentration of 10 mg / mL was spin-coated on the FTO glass at 3000 rpm for 40 seconds, followed by annealing at 150° C. for 15 minutes to obtain a NiOx layer with a thickness of 20 nm.

[0129] The surface of the obtained NiOx layer was spin-coated with an M2P solution having a concentration of 0.3 mg / mL at 5000 rpm for 30 seconds, followed by annealing at 100° C. for 10 minutes to obtain an M2P layer with a thickness of 1 nm.

[0130] The perovskite precursor solution (concentration 1.5M) was coated on the hole transport layer formed by NiOx and M2P, and the solution was spin-coated at 1000rpm for 10s, and then at 5000rpm for 30s. At the 20th second, 150uL of chlorobenzene antisolvent was added, and then annealed at 100℃ for 30 minutes. After annealing, the solution was cooled to room temperature. A perovskite layer with a thickness of 800nm ​​was obtained, in which the perovskite material was Cs 0.05 FA 0.85 MA 0.1 PbI3.

[0131] Continue to spin-coat the passivation solution on the perovskite layer. The passivation solution is formed by dissolving the passivation material prepared in step (1) in isopropanol solvent. The passivation concentration is 0.1 mg / mL. Spin-coat at 5000 rpm for 30 seconds, and then anneal at 100° C. for 10 minutes. After cooling, use pure isopropanol solvent again, spin-coat at 5000 rpm for 30 seconds. Then anneal at 100° C. for 5 minutes. A passivation layer with a thickness of 3 nm is formed.

[0132] A 20 nm thick C60 layer (fullerene layer) was formed on the passivation layer by evaporation, and a 7 nm thick BCP layer was formed on the C60 layer by evaporation. The C60 layer and the BCP layer served as electron transport layers.

[0133] A Cu electrode with a thickness of 100 nm was formed on the BCP layer by vapor deposition.

[0134] The structure of the obtained inverted solar cell device is: FTO / NiOx / M2P / perovskite layer / passivation layer / C60 / BCP / Cu.

[0135] Embodiment 2-9

[0136] (1) The preparation method of the passivation material is basically the same as that of Example 1, except that different raw materials are used.

[0137] (2) Similar to Example 1, the prepared passivation material was confirmed using NMR.

[0138] (3) The preparation method of the solar cell device is the same as that of Example 1.

[0139] Example 10

[0140] (1) The preparation method of the passivation material is basically the same as that of Example 1, except that different raw materials are used.

[0141] (2) Similar to Example 1, the prepared passivation material was confirmed using NMR.

[0142] (3) The preparation method of the solar cell device with a formal structure is as follows:

[0143] A SnO2 nanoparticle solution with a mass concentration of 2.26 mg / mL was spin-coated on the FTO glass at 4000 rpm for 30 seconds, followed by annealing at 150°C for 15 minutes to obtain a SnO2 layer with a thickness of 20 nm.

[0144] The obtained substrate was transferred to a glove box, and a passivation solution was spin-coated on the SnO2 layer at 5000 rpm for 30 seconds, followed by annealing at 100°C for 10 minutes to form a passivation layer with a thickness of 3 nm. The passivation solution was obtained by dissolving the passivation material in isopropanol solvent, wherein the concentration of the passivation material was 0.1 mg / mL.

[0145] The perovskite precursor solution (concentration 1.5M) was spin-coated on the passivation layer at 1000rpm for 10s, then at 5000rpm for 30s. At the 20th second, 150uL of chlorobenzene antisolvent was added, and then annealed at 100℃ for 30 minutes. After annealing, it was cooled to room temperature. A perovskite layer with a thickness of 800nm ​​was obtained, in which the perovskite material was Cs 0.05 FA 0.85 MA 0.1 PbI3.

[0146] 72.3 mg of Spiro-OMeTAD powder was dissolved in 1 mL of chlorobenzene. After complete dissolution, 28.5 mL of TBP (4-tert-butylpyridine) solution and 17.5 mL of bis(trifluoromethane)sulfonamide lithium salt solution (520 mg / mL acetonitrile solution) were added and stirred for 10 minutes. The perovskite layer was spin-coated at 3000 rpm for 30 seconds. A Spiro-MeOTAD layer with a thickness of 50 nm was obtained.

[0147] An Au electrode with a thickness of 100 nm was formed on the Spiro-MeOTAD layer by vapor deposition.

[0148] The structure of the obtained formal structure of the solar cell device is: FTO / SnO2 / passivation layer / perovskite / Spiro-MeOTAD / Au.

[0149] Examples 11-12

[0150] (1) The preparation method of the passivation material is basically the same as that of Example 1, except that different raw materials are used, specifically, HI is replaced by HBr and HCl respectively.

[0151] (2) Similar to Example 1, the prepared passivation material was confirmed using NMR.

[0152] (3) The preparation method of the solar cell device is the same as that of Example 1.

[0153] Examples 13-14

[0154] (1) The preparation method of the passivation material is the same as that of Example 1.

[0155] (2) Similar to Example 1, the prepared passivation material was confirmed using NMR.

[0156] (3) The preparation method of the solar cell device is basically the same as that of Example 1, except that the thickness of the passivation layer is different.

[0157] Comparative Example 1

[0158] The method for preparing the solar cell device is the same as that of Example 1, except that no passivation layer is provided.

[0159] Comparative Example 2

[0160] The method for preparing the solar cell device is the same as that of Example 10, except that no passivation layer is provided.

[0161] Comparative Example 3

[0162] The preparation method of the solar cell device is the same as that of Example 1, except that the passivation material uses commercially available N-butyl-N-methylpiperidinium bis(trifluoromethanesulfonyl)imide salt (CAS No.: 623580-02-9).

[0163] Comparative Examples 4-5

[0164] (1) The preparation method of the passivation material is basically the same as that of Example 1, except that different raw materials are used.

[0165] (2) Similar to Example 1, the prepared passivation material was confirmed using NMR.

[0166] (3) The preparation method of the solar cell device is the same as that of Example 1.

[0167] Comparative Example 6

[0168] The preparation method of the solar cell device is the same as that of Example 1, except that the passivation material uses commercially available 4-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]morpholine (CAS No.: 852227-95-3).

[0169] Performance Testing

[0170] In standard simulated sunlight (AM 1.5G, 100mW / cm 2 ) irradiation, the battery performance is tested to obtain the IV curve. 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.

[0171] The open circuit voltage change rate of the battery of Examples 1-9, Examples 11-14, and Comparative Examples 3-6 is calculated based on the open circuit voltage of the battery of Comparative Example 1. The photoelectric conversion efficiency PCE of the battery of Examples 1-9, Examples 11-14, and Comparative Examples 3-6 is calculated based on the photoelectric conversion efficiency PCE of the battery of Comparative Example 1.

[0172] The open circuit voltage change rate of the battery of Example 10 is calculated based on the open circuit voltage of the battery of Comparative Example 2. The photoelectric conversion efficiency PCE of the battery of Example 10 is calculated based on the photoelectric conversion efficiency PCE of the battery of Comparative Example 2.

[0173] For example: the open circuit voltage change rate of the battery of Example 1 = the open circuit voltage of the battery of Example 1 / the open circuit voltage of the battery of Comparative Example 1 - 100%;

[0174] The open circuit voltage change rate of the battery of Example 10 = the open circuit voltage of the battery of Example 10 / the open circuit voltage of the battery of Comparative Example 2 - 100%;

[0175] The photoelectric conversion efficiency change rate of the battery of Example 1 = the photoelectric conversion efficiency of the battery of Example 1 / the photoelectric conversion efficiency of the battery of Comparative Example 1 - 100%;

[0176] The change rate of the photoelectric conversion efficiency of the battery of Example 10 = the photoelectric conversion efficiency of the battery of Example 10 / the photoelectric conversion efficiency of the battery of Comparative Example 2 - 100%.

[0177] According to the experimental results, the open circuit voltage of the battery of Comparative Example 1 is 1.08V, and the photoelectric conversion efficiency PCE is 21%. The open circuit voltage of the battery of Comparative Example 2 is 1.07V, and the photoelectric conversion efficiency PCE is 20%.

[0178] Table 1 Product parameters and performance parameters of each embodiment and comparative example

[0179]

[0180]

[0181] It can be seen from the data in Table 1 that the open circuit voltage change rate and the photoelectric conversion efficiency change rate of the batteries of Examples 1-9 and Examples 11-14 are higher than those of the corresponding comparative examples 1 and 3-6. The open circuit voltage change rate and the photoelectric conversion efficiency change rate of the battery of Example 10 are significantly improved relative to the open circuit voltage change rate and the photoelectric conversion efficiency change rate of the battery of Comparative Example 2, indicating that the passivation material nitrogen heterocyclic halide of Examples 1-14 is arranged between the perovskite layer and the electron transport layer, which effectively improves the open circuit voltage and the photoelectric conversion efficiency of the perovskite solar cell.

[0182] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0183] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims, and the specification and drawings may be used to interpret the contents of the claims.

Claims

1. A perovskite solar cell, characterized in that: The invention comprises a first electrode, a perovskite layer, a passivation layer, an electron transport layer and a second electrode which are stacked in sequence, wherein the passivation layer comprises a nitrogen heterocyclic halide, wherein the H on the nitrogen heterocyclic ring of the nitrogen heterocyclic halide is not substituted or at least one H is substituted by a substituent.

2. The perovskite solar cell according to claim 1, characterized in that The substituent is located at the nitrogen ring atom of the nitrogen heterocycle or at the ortho-para position thereof.

3. The perovskite solar cell according to claim 1 or 2, characterized in that: The nitrogen heterocycle includes at least one of a five-membered nitrogen heterocycle, a six-membered nitrogen heterocycle and a condensed nitrogen heterocycle; 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 and thiazole; Optionally, the number of nitrogen ring atoms in the six-membered nitrogen heterocycle is 1 to 4, and more preferably 1 to 3; more preferably, the six-membered nitrogen heterocycle includes at least one of pyridine, piperidine, pyrimidine, morpholine, thiomorpholine, monoazacyclohexane, 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 purine, indole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, furanopyrrole, benzisothiazole, benzimidazole, quinoline, isoquinoline, quinoxaline and quinazoline.

4. The perovskite solar cell according to claim 1 or 2, characterized in that: The substituent includes -N-R2HX, R includes any one of H, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl and substituted or unsubstituted heterocyclic, and multiple Xs each independently include Cl - Br - ,I - ; Optionally, the alkyl group includes a C1 to C8 alkyl group; Optionally, the cycloalkyl group includes a C3-C8 cycloalkyl group; Optionally, the heterocyclic group includes a C4-C8 heterocyclic group.

5. The perovskite solar cell according to claim 1 or 2, characterized in that: The nitrogen heterocyclic halide comprises at least one of Formula 1 to Formula 9: In Formulae 1 to 9, the plurality of Xs each independently include Cl, Br, and I.

6. The perovskite solar cell according to claim 1 or 2, characterized in that: The thickness of the passivation layer is less than 10 nm, and can be selected to be 0.1 nm to 5 nm.

7. The method for preparing a perovskite solar cell according to any one of claims 1 to 6, characterized in that: include: The step of forming the first electrode, the perovskite layer, the passivation layer, the electron transport layer and the second electrode.

8. A photovoltaic module, characterized in that: A perovskite solar cell comprising the perovskite solar cell according to any one of claims 1 to 6 or a perovskite solar cell prepared by the preparation method according to claim 7.

9. A photovoltaic system, characterized in that: Comprising the photovoltaic module described in claim 8.

10. An electrical device, characterized in that: A perovskite solar cell comprising the perovskite solar cell according to any one of claims 1 to 6 or a perovskite solar cell prepared by the preparation method according to claim 7.

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