Perovskite precursor solution, perovskite thin film, preparation method of perovskite thin film, photovoltaic device and power utilization device

Abstract

The invention relates to the technical field of photoelectric devices, in particular to a perovskite precursor solution, a perovskite thin film, a preparation method of the perovskite thin film, a photovoltaic device and an electric device. The invention provides a perovskite precursor solution. The perovskite precursor solution provided by the invention comprises a perovskite precursor, a solvent and thiocycloalkane, the thiocycloalkane is selected from one or more of compounds with structural characteristics as shown in a formula (I-1)-a formula (I-3). The thiocycloalkane added into the perovskite precursor solution provided by the invention can effectively participate in the crystallization process of the perovskite material, so that the crystallinity of the perovskite material is increased, defects are reduced, and the photoelectric property is improved.

Description

Technical Field

[0001] The present application relates to the technical field of optoelectronic devices, and in particular to a perovskite precursor solution, a perovskite film and a preparation method thereof, a photovoltaic device, and an electrical device. Background Art

[0002] Perovskite materials are a type of material with an ABX3 molecular structure composed of cations (A), divalent metal cations (B) and halogen ions (X). Under sunlight, the excitons in the perovskite layer are dissociated to produce free carriers. The electrons move freely to the cathode, and the holes move freely to the anode, forming a potential difference and generating current. The perovskite materials have the advantages of high absorption coefficient, adjustable band gap, long carrier lifetime, etc., which effectively improves the power conversion efficiency (PCE) of solar cells.

[0003] The crystallization process of perovskite materials is complex, and the crystal structure will be affected by crystal growth and its post-processing process, resulting in defects. These defects will introduce transition levels in the bandgap, and shallow energy level defects will be formed when the transition level is close to the valence band or conduction band. Carriers trapped by shallow energy level traps are easily detrapped, so shallow energy level defects have little effect on carrier recombination. Deep energy level defects will be formed when the transition energy level is located in the middle 1 / 3 of the bandgap. They will firmly capture electrons or holes to form recombination centers, which is not conducive to the extraction of carriers in perovskites and will seriously affect the optoelectronic performance. Summary of the invention

[0004] Based on this, the present application provides a perovskite precursor solution, a perovskite film and a preparation method thereof, a photovoltaic device, and an electrical device. The thiocycloalkane added to the perovskite precursor solution provided in the present application can effectively participate in the crystallization process of the perovskite material, promote the increase of the crystallinity of the perovskite material and reduce defects, and improve the photoelectric performance.

[0005] In a first aspect of the present application, a perovskite precursor solution is provided, wherein the perovskite precursor solution comprises a perovskite precursor, a solvent and a thiocycloalkane; the thiocycloalkane is selected from one or more compounds having structural features shown in formula (I-1) to formula (I-3):

[0006] , and ;

[0007] x 11 and x 12 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 11 and x 12 At least one of them is S; y 11 and12 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 11 and 12 At least one of them is C(=O); R1 and R2 are each independently H, substituted or unsubstituted C1~C6 alkyl;

[0008] x 21 and x 22 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 21 and x 22 At least one of them is S; y 21 ,y 22 and 23 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 21 ,y 22 and 23 At least one of them is C(=O);

[0009] x 31 、x 32 、x 33 and x 34 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 31 、x 32 、x 33 and x 34 At least one of them is S; y 31 and 32 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 31 and 32 At least one of them is C(=O);

[0010] Wherein, R, R′ and R′′ are each independently H, or a substituted or unsubstituted C1~C6 alkyl group.

[0011] In one embodiment, x 11 and x 12 are each independently S, C(RR′) or N(R′′), and x 11 and x 12 At least one of them is S; y 11 and 12 are each independently C(RR′), C(═O) or C(═S), and y 11 and 12 At least one of them is C(=O); R1 and R2 are each independently H, substituted or unsubstituted C1~C3 alkyl;

[0012] x 21 and x 22 are each independently S, C(RR′) or N(R′′), and x 21 and x 22 At least one of them is S; y 21 ,y 22 and 23 are each independently C(RR′), C(═O) or C(═S), and y 21 ,y 22 and 23 At least one of them is C(=O);

[0013] x 31 、x 32 、x 33 and x 34 are each independently S, C(RR′) or N(R′′), and x 31 、x 32 、x 33 and x 34 At least one of them is S; y 31 and 32 are each independently C(RR′), C(═O) or C(═S), and y 31 and 32 At least one of them is C(=O);

[0014] Wherein, R, R′ and R′′ are each independently H, or a substituted or unsubstituted C1~C3 alkyl group.

[0015] In one embodiment, the thiocycloalkane is selected from one or more compounds having structural features shown in formula (II-1) to formula (II-24):

[0016]

[0017]

[0018]

[0019]

[0020]

[0021] ;

[0022] Wherein, R1 and R2 are each independently H, substituted or unsubstituted C1~C6 alkyl;

[0023] R, R' and R'' are each independently H, or a substituted or unsubstituted C1-C6 alkyl group.

[0024] In one embodiment, the thiocycloalkane is selected from one or more compounds having structural features shown in formula (III-1) to formula (III-6):

[0025] .

[0026] In one of the embodiments, in the perovskite precursor solution, the mass ratio of the thiocycloalkane to the perovskite precursor is (0.0003~0.001):(0.9~2).

[0027] In one embodiment, the concentration of the perovskite precursor in the perovskite precursor solution is 0.8 mol / L~3 mol / L.

[0028] In one embodiment, the perovskite precursor includes ABX3 material;

[0029] Among them, A includes FA + 、MA + , Cs + , Rb + and K + One or more of, B includes Pb 2+ Sn 2+ and Ge 2+ One or more of, X is Cl - Br - and I - One or more of.

[0030] A second aspect of the present application provides a method for preparing a perovskite film, comprising the following steps:

[0031] The perovskite precursor film is formed on a substrate using the perovskite precursor solution described in any one of the embodiments of the first aspect of the present application, and the perovskite precursor film is annealed to obtain the perovskite film.

[0032] In a third aspect of the present application, a perovskite film is prepared using the perovskite precursor solution described in any embodiment of the first aspect of the present application, or contains the thiocycloalkane in the perovskite precursor solution described in any embodiment of the first aspect of the present application.

[0033] In one of the embodiments, the mass ratio of the thiocycloalkane to the perovskite precursor in the perovskite film is (0.0003~0.001):(0.9~2).

[0034] In one embodiment, the thickness of the perovskite film is 300nm~1000nm.

[0035] According to a fourth aspect of the present application, a photovoltaic device is provided, wherein the photovoltaic device comprises a perovskite film, and the perovskite film is the perovskite film described in any one of the embodiments of the third aspect of the present application.

[0036] The fifth aspect of the present application provides an electrical device, comprising the photovoltaic device described in the fourth aspect of the present application.

[0037] The thiocycloalkane added to the perovskite precursor solution provided in the present application has strong coordination between the oxygen atoms and sulfur atoms in the thiocycloalkane and the divalent metal cation (B), which can inhibit the formation of the perovskite intermediate phase and reduce the lattice distortion; and promote the directional crystallization of the perovskite material, increase the grain size of the perovskite material, and reduce the number of grain boundaries. In addition, the C (=O) group contained in the thiocycloalkane can combine with the low-coordinated divalent metal cation (B) near the halogen ion (X); at the same time, the sulfur-containing heterocycle contained in the thiocycloalkane acts as a Lewis basic functional group, which can passivate the divalent metal cation (B) on the surface as a Lewis acid; and the thiocycloalkane can be distributed on the surface and grain boundaries of the perovskite, and it can actively fill the carrier defects on the grain boundaries and surfaces; under the above-mentioned synergistic effect, the thiocycloalkane provided in the present application can effectively reduce the vacancy defects and grain boundary surface defects of the low-coordinated divalent metal cation (B), so as to improve the carrier extraction efficiency of the perovskite solar cell and enhance the photoelectric performance of the perovskite solar cell.

[0038] In addition, since thiocycloalkanes can effectively promote the increase of crystallinity of perovskite materials, reduce grain boundaries and reduce defects, the prepared perovskite films can exhibit lower water and oxygen erosion rates, which will be beneficial to the improvement of thermal stability and environmental stability of perovskite solar cells.

[0039] Furthermore, the present application directly adds thiocycloalkanes into the perovskite precursor solution, which will not affect the large-area preparation process of the perovskite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1A schematic diagram of the structure of a perovskite solar cell provided in one embodiment of the present application, wherein 10 is a solar cell; 101 is a transparent conductive layer; 102 is a first transmission layer; 103 is a perovskite film layer; 104 is a second transmission layer; 105 is an electrode;

[0042] Figure 2 JV curves of perovskite solar cells prepared in the examples and comparative examples of the present application;

[0043] Figure 3 This is a thermal stability curve diagram of the perovskite solar cells prepared in the examples and comparative examples of the present application. DETAILED DESCRIPTION

[0044] The following is a further complete and clear description of the perovskite precursor solution, perovskite film and preparation method thereof, photovoltaic device, and power device of the present application in conjunction with specific embodiments. The present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0045] In the present application, "substituted" means that a hydrogen atom in a substituted group is replaced by a substituent.

[0046] In the present invention, "substituted or unsubstituted" means that the defined group may be substituted or unsubstituted. When the defined group is substituted, it should be understood that it is optionally substituted by a group acceptable in the art, including but not limited to: C1~C5 alkyl, silyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, haloformyl, formyl, -NQQ', cyano, isocyano, isocyanate, thiocyanate, isothiocyanate, hydroxyl, trifluoromethyl, nitro or halogen, and the above groups may also be further substituted by substituents acceptable in the art; it is understood that Q and Q' in -NQQ' are each independently substituted by a group acceptable in the art, including but not limited to H, C1~C5 alkyl, halogen, hydroxyl, nitro or amino.

[0047] In the present application, "alkyl" may represent a straight chain, branched chain and / or cyclic alkyl. Phrases containing this term, for example, "C1-C6 alkyl" refers to an alkyl group containing 1 to 6 carbon atoms, each occurrence of which may be independently C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 4-methyl-2-pentyl, n-hexyl or cyclohexyl.

[0048] The divalent metal cations (B) and halogen ions (X) of the perovskite precursor can form nanoscale nucleation centers in the solution. Therefore, the crystallization process of perovskite usually starts from the divalent metal cation (B)-halogen ion (X) framework. In order to delay the nucleation and crystallization of perovskite and make the film grains in the obtained perovskite film dense and uniform, the current main method is to introduce a passivating agent into the perovskite precursor solution to control the crystal phase structure, reduce phase change and reduce defects.

[0049] At present, the commonly used passivators are mainly alkylamines and their halides, aromatic amines and their halides, including ethylamine, n-butylamine, phenylethylamine, octylamine, dioctylamine iodide, etc. The traditionally used alkylamines and their halides, aromatic amines and their halides will agglomerate during the preparation process of perovskite films, which will weaken the passivation effect on perovskite films; in addition, alkylamines and their halides, aromatic amines and their halides can only passivate a single defect, that is, they can only choose between halogen ions (X) or divalent metal cations (B) to passivate vacancy defects; alkylamines and their halides, aromatic amines and their halides cannot passivate surface defects such as grain boundaries.

[0050] Therefore, how to improve crystallization, effectively reduce perovskite defects, and improve photoelectric performance has become a technical problem that urgently needs to be solved.

[0051] Based on this, the first aspect of the present application provides a perovskite precursor solution, the perovskite precursor solution comprising a perovskite precursor, a solvent and a thiocycloalkane; the thiocycloalkane is selected from one or more compounds having structural features shown in formula (I-1) to formula (I-3):

[0052] , and ;

[0053] x 11 and x 12 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 11 and x 12 At least one of them is S; y 11 and 12 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 11 and 12 At least one of them is C(=O); R1 and R2 are each independently H, substituted or unsubstituted C1~C6 alkyl;

[0054] x 21 and x 22are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 21 and x 22 At least one of them is S; y 21 ,y 22 and 23 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 21 ,y 22 and 23 At least one of them is C(=O);

[0055] x 31 、x 32 、x 33 and x 34 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 31 、x 32 、x 33 and x 34 At least one of them is S; y 31 and 32 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 31 and 32 At least one of them is C(=O);

[0056] Wherein, R, R′ and R′′ are each independently H, or a substituted or unsubstituted C1~C6 alkyl group.

[0057] In one example, x 11 and x 12 are each independently S, C(RR′) or N(R′′), and x 11 and x 12 At least one of them is S; y 11 and 12 are each independently C(RR′), C(═O) or C(═S), and y 11 and 12 At least one of them is C(=O); R1 and R2 are each independently H, substituted or unsubstituted C1~C3 alkyl;

[0058] x 21 and x 22 are each independently S, C(RR′) or N(R′′), and x 21 and x 22 At least one of them is S; y 21 ,y 22 and 23 are each independently C(RR′), C(═O) or C(═S), and y21 ,y 22 and 23 At least one of them is C(=O);

[0059] x 31 、x 32 、x 33 and x 34 are each independently S, C(RR′) or N(R′′), and x 31 、x 32 、x 33 and x 34 At least one of them is S; y 31 and 32 are each independently C(RR′), C(═O) or C(═S), and y 31 and 32 At least one of them is C(=O);

[0060] Wherein, R, R′ and R′′ are each independently H, or a substituted or unsubstituted C1~C3 alkyl group.

[0061] The thiocycloalkane added to the perovskite precursor solution provided in the present application has strong coordination between the oxygen atom and sulfur atom of C (=O) in the thiocycloalkane and the divalent metal cation (B), which can inhibit the formation of the perovskite intermediate phase and reduce the lattice distortion; and promote the directional crystallization of the perovskite material, increase the grain size of the perovskite material, and reduce the number of grain boundaries. In addition, the C (=O) group contained in the thiocycloalkane can combine with the low-coordinated divalent metal cation (B) near the halogen ion (X); at the same time, the sulfur-containing heterocycle contained in the thiocycloalkane acts as a Lewis basic functional group, which can passivate the divalent metal cation (B) on the surface as a Lewis acid; and the thiocycloalkane can be distributed on the surface and grain boundaries of the perovskite, and it can actively fill the carrier defects on the grain boundaries and surfaces; under the above-mentioned synergistic effect, the thiocycloalkane provided in the present application can effectively reduce the vacancy defects and grain boundary surface defects of the low-coordinated divalent metal cation (B), so as to improve the carrier extraction efficiency of the perovskite solar cell and enhance the photoelectric performance of the perovskite solar cell.

[0062] In addition, since thiocycloalkanes can effectively promote the increase of crystallinity of perovskite materials, reduce grain boundaries and reduce defects, the prepared perovskite films can exhibit lower water and oxygen erosion rates, which will be beneficial to the improvement of thermal stability and environmental stability of perovskite solar cells.

[0063] Furthermore, the present application directly adds thiocycloalkanes into the perovskite precursor solution, which will not affect the large-area preparation process of the perovskite material.

[0064] In one example, the thiocycloalkane is selected from one or more compounds having structural features shown in formula (II-1) to formula (II-24):

[0065]

[0066]

[0067]

[0068]

[0069]

[0070] ;

[0071] Wherein, R1 and R2 are each independently H, substituted or unsubstituted C1~C6 alkyl;

[0072] R, R' and R'' are each independently H, or a substituted or unsubstituted C1-C6 alkyl group.

[0073] In one specific example, the thiocycloalkane is selected from one or more compounds having structural features shown in Formula (III-1) to Formula (III-6):

[0074] .

[0075] In one example, x 11 and x 12 S, y 11 and 12 is C(=O), R1 and R2 are each independently H, C1~C3 alkyl. For example, the thiocycloalkane includes and One or more of. 11 and x 12 S, y 11 and 12When it is C(=O), the two C(=O) groups contained in the thiocycloalkane can form a strong coordination effect with the divalent metal cation (B) to interfere with the nucleation and generation process of the perovskite material; at the same time, the two Ss make the sulfur-containing heterocyclic ring in the thiocycloalkane as a Lewis basic functional group, which can bind to the divalent metal cation (B) on the surface or grain boundary, passivate the Lewis acid sites at these positions, reduce the carrier traps caused by these sites, and further optimize the charge transfer path. In addition, R1 and R2 are independently H, C1~C3 alkyl, which can also appropriately produce a certain steric effect on the sulfur-containing heterocyclic ring to prevent excessive passivation of the thiocycloalkane.

[0076] In one example, in the perovskite precursor solution, the mass ratio of the thiocycloalkane to the perovskite precursor is (0.0003~0.001): (0.9~2). By limiting the mass ratio of thiocycloalkane to perovskite precursor, lattice distortion, vacancy defects and grain boundary surface defects can be effectively suppressed to improve the carrier extraction efficiency of perovskite solar cells. If less thiocycloalkane is added, the role of thiocycloalkane as a passivator may be limited, and the lattice distortion and defect formation of the perovskite material cannot be effectively suppressed, resulting in reduced photoelectric performance. If more thiocycloalkane is added, it may cause excessive passivation effect and affect the normal crystallization of the perovskite material. Specifically, in the perovskite precursor solution, the mass ratio of the thiocycloalkane to the perovskite precursor includes but is not limited to 0.0003:0.96, 0.0005:0.96, 0.0007:0.96, 0.0009:0.96, 0.001:0.96, 0.0003:1.1, 0.0005:1.1, 0.0007:1.1, 0.0009:1.1, 0.001:1.1, 0.0005:1.15, 0.0007:1.15, 0.0009:1.15, 0.001:1.15, 0.001:1.3, 0.001:1.5, 0.001:1.8 or 0.001:2.

[0077] In one example, the concentration of the perovskite precursor in the perovskite precursor solution is 0.8 mol / L to 3 mol / L. Specifically, the concentration of the perovskite precursor includes but is not limited to 0.8 mol / L, 1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.8 mol / L, 2 mol / L, 2.5 mol / L or 3 mol / L.

[0078] In one example, the perovskite precursor includes ABX3 material, wherein A includes FA + 、MA+ , Cs + , Rb + and K + One or more of, B includes Pb 2+ Sn 2+ and Ge 2+ One or more of, X is Cl - Br - and I - One or more of.

[0079] In one example, the solvent includes one or more of N,N-dimethylformamide, N-methylpyrrolidone, acetonitrile, dimethyl sulfoxide, ethanol and acetone.

[0080] The present application also provides a method for preparing a perovskite precursor solution, the preparation method comprising: mixing a perovskite precursor, a solvent and a thiocycloalkane to obtain the perovskite precursor solution.

[0081] A second aspect of the present application provides a method for preparing a perovskite film, comprising the following steps:

[0082] The perovskite precursor film is formed on a substrate using the perovskite precursor solution described in any example of the first aspect of the present application, and the perovskite precursor film is annealed to obtain the perovskite film.

[0083] In one example, the step of forming a perovskite precursor film on a substrate using the perovskite precursor solution described in any example of the first aspect of the present application includes coating and removing the solvent. The coating method includes but is not limited to spin coating, spray coating, slit coating or scraping. The method of removing the solvent includes but is not limited to heating, anti-solvent, vacuum or flash evaporation.

[0084] In the present application, the method of forming a perovskite precursor film on a substrate using the perovskite precursor solution described in any example of the first aspect of the present application is preferably a spin coating method. The ABX3 structural component of the perovskite film prepared by the spin coating method is usually ABI3 or ABI x Br 3-x or ABI x Br y Cl 3-x-y , at this time, the proportion of x is usually between 2 and 3.

[0085] In addition, when preparing the perovskite film, in order to improve the crystallization of the perovskite film, additives are added to the perovskite precursor solution; during the annealing process, the additives volatilize and do not exist in the perovskite film. In addition, additives can also be added to the perovskite precursor solution to adjust the perovskite band gap and improve the optical properties of the perovskite film. For example, the types of additives include but are not limited to any one or more combinations of MACl, PbCl2, MABr, FAI, ammonium chloride and ammonium bromide. More specifically, in the perovskite precursor solution, the mass ratio of the additive to the perovskite precursor is (0.05~0.2): 1. The mass ratio of the additive to the perovskite precursor includes but is not limited to 0.05:1, 0.08:1, 0.09:1, 0.1:1, 0.11:1, 0.12:1, 0.13:1, 0.15:1, 0.18:1 or 0.2:1.

[0086] In one example, the annealing temperature is 80° C. to 120° C. Specifically, the annealing temperature includes but is not limited to 80° C., 85° C., 90° C., 95° C., 98° C., 100° C., 102° C., 105° C., 110° C. or 120° C.

[0087] In a third aspect of the present application, a perovskite film is prepared using the perovskite precursor solution described in any example of the first aspect of the present application.

[0088] In one example, the mass ratio of the thiocycloalkane to the perovskite precursor in the perovskite film is (0.0003~0.001):(0.9~2). Specifically, in the perovskite film, the mass ratio of the thiocycloalkane to the perovskite precursor includes but is not limited to 0.0003:0.96, 0.0005:0.96, 0.0007:0.96, 0.0009:0.96, 0.001:0.96, 0.0003:1.1, 0.0005:1.1, 0.0007:1.1, 0.0009:1.1, 0.001:1.1, 0.0005:1.15, 0.0007:1.15, 0.0009:1.15, 0.001:1.15, 0.001:1.3, 0.001:1.5, 0.001:1.8 or 0.001:2.

[0089] The thickness of the perovskite film affects light absorption and the diffusion length of carriers. In one example, the thickness of the perovskite film is 300 nm to 1000 nm. Specifically, the thickness of the perovskite film includes but is not limited to 300 nm, 500 nm, 700 nm, 900 nm or 1000 nm.

[0090] In a fourth aspect of the present application, a photovoltaic device is provided, the photovoltaic device comprising a perovskite film layer, the perovskite film layer being the perovskite film described in any example of the third aspect of the present application. The photovoltaic devices mentioned in the present application include but are not limited to perovskite solar cells, two-terminal stacked perovskite solar cells with a bottom cell of silicon / CdTe / CIGS, and four-terminal stacked cells with a bottom cell of silicon / CdTe / CIGS.

[0091] In one example, the photovoltaic device is a perovskite solar cell. Figure 1 As shown, the perovskite solar cell 10 includes a transparent conductive layer 101, a first transmission layer 102, a perovskite thin film layer 103, a second transmission layer 104 and an electrode 105 which are stacked in sequence.

[0092] In one example, the first transport layer 102 is an electron transport layer, and the second transport layer 104 is a hole transport layer.

[0093] In another example, the first transport layer 102 is a hole transport layer, and the second transport layer 104 is an electron transport layer.

[0094] In one example, the material of the transparent conductive layer 101 includes one or more of indium-doped tin oxide (ITO), fluorine-doped tin oxide (FTO), indium-doped zinc oxide (IZO), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), indium-doped tungsten oxide (IWO), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyimide (PI) and polydimethylsiloxane (PDMS).

[0095] In one example, the thickness of the transparent conductive layer 101 is 10 nm to 1000 nm. Specifically, the thickness of the transparent conductive layer 101 includes but is not limited to 20 nm, 30 nm, 50 nm, 80 nm, 100 nm, 150 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm or 1000 nm.

[0096] In one example, the material of the electron transport layer includes one or more of titanium dioxide (TiO2), tin dioxide (SnO2), indium oxide (In2O3), zinc oxide (ZnO), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), fullerene derivatives, graphene, and graphene derivatives. For example, fullerene derivatives include but are not limited to PCBM and C60.

[0097] In one example, the thickness of the electron transport layer is 10 nm to 200 nm. Specifically, the thickness of the electron transport layer includes but is not limited to 20 nm, 30 nm, 35 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 150 nm, 180 nm or 200 nm.

[0098] In one example, the hole transport layer includes cuprous thiocyanate (CuSCN), cuprous iodide (CuI), nickel oxide (NiO x ), molybdenum oxide (MoO x ), tungsten oxide (WO x ), poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (2PACz) and its derivatives, 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid and its derivatives and self-assembled monolayer SAM materials. For example, the self-assembled monolayer SAM material includes one or more of carbazole and porphyrin materials.

[0099] In one example, the thickness of the hole transport layer is 10 nm to 200 nm. Specifically, the thickness of the hole transport layer includes but is not limited to 20 nm, 30 nm, 40 nm, 60 nm, 80 nm, 100 nm, 120 nm, 140 nm, 160 nm, 180 nm or 200 nm.

[0100] In one example, the material of the electrode 105 includes one or more of gold (Au), silver (Ag), copper (Cu), aluminum (Al), titanium (Ti), nickel (Ni), and molybdenum (Mo).

[0101] In one example, the thickness of the electrode 105 is 10 nm to 5000 nm. Specifically, the thickness of the electrode 105 includes but is not limited to 20 nm, 50 nm, 100 nm, 500 nm, 800 nm, 1000 nm, 1500 nm, 2000 nm, 2500 nm, 3000 nm, 3500 nm, 4000 nm, 4500 nm or 5000 nm.

[0102] In one example, the preparation method of the electron transport layer and the hole transport layer includes one or more thin film preparation methods such as spin coating, slit coating, doctor blade coating, screen printing, inkjet printing, evaporation, magnetron sputtering, physical vapor deposition (PVD), etc. Optionally, the preparation methods of the electron transport layer and the hole transport layer can be the same or different.

[0103] The fifth aspect of the present application provides an electrical device, comprising the photovoltaic device described in the fourth aspect of the present application.

[0104] The following further specific examples are provided to explain the present application in detail. It should also be understood that the following examples are only used to further explain the present application and cannot be understood as limiting the scope of protection of the present application. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present application belong to the scope of protection of the present application. The specific process parameters of the following embodiments are also only examples within a suitable range, that is, those skilled in the art can make a selection within a suitable range through the description herein, and are not necessarily limited to the specific values ​​of the embodiments below.

[0105] [Thiocycloalkanes]

[0106] Thiocycloalkane P1, structural formula: ; Disulfide was prepared according to the preparation method of Hans R. Kricheldorf, Nino Lomadze, and Gert Schwarz; "Cyclic Poly (thioglycolide) and Poly (D, L-thiolactide) by Zwitterionic Polymerization of Dithiolane-2,4-diones"; Macromolecules 2007, 40, 4859-4864.

[0107] Thiocycloalkane P2: Structural formula: , prepared by referring to the preparation method of Chinese patent document CN101260101A.

[0108] Thiocycloalkane P3, structural formula: , CAS: 51338-33-1, commercially available;

[0109] Thiocycloalkane P4, structural formula: , CAS: 3194-60-3, commercially available.

[0110] Example 1

[0111] Perovskite precursor solution: 0.96 g of perovskite precursor FA 0.9 Cs0.1 PbI3 and 0.01g additive MACl were dissolved in 1mL of solvent with a volume ratio of DMF:NMP=4:1, and 0.5mg of thiocycloalkane P1 and 1.5mg of 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid as hole transport material were added, and stirred to dissolve to obtain a perovskite precursor solution. Among them, in the perovskite precursor solution, FA 0.9 Cs 0.1 The molar concentration of PbI3 is 1.5 mol / L.

[0112] The preparation steps of perovskite solar cells include:

[0113] (1) The ITO conductive glass was ultrasonically cleaned with glass cleaning liquid, deionized water, and ethanol for 20 min respectively, and finally dried in a drying oven at 75°C for later use; the dried ITO glass substrate was placed in a UV ozone machine for 20 min to remove organic impurities on its surface and optimize its surface wettability;

[0114] (2) In a nitrogen glove box, take 60 μL of perovskite precursor solution and spin coat it on the surface of the ITO substrate at a speed of 5000 rpm / min and an acceleration of 1000 rpm / s for 50 seconds. After completion, transfer it to an annealing hot plate and heat it at 100°C for 40 minutes to complete annealing; to form a 60nm hole transport layer and a 500nm perovskite film layer;

[0115] (3) 20 nm of C60 and 15 nm of BCP were sequentially deposited on the surface of the perovskite film layer as an electron transport layer;

[0116] (4) Evaporating 150 nm of Ag on the surface of the electron transport layer as an electrode layer to prepare a perovskite solar cell.

[0117] Example 2

[0118] Perovskite precursor solution: 0.96 g of perovskite precursor FA 0.9 Cs 0.1 PbI3 and 0.01g additive MACl were dissolved in 1mL of solvent with a volume ratio of DMF:NMP=4:1, and 1mg of thiocycloalkane P1 and 1.5mg of 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid as hole transport material were added, and stirred to dissolve to obtain a perovskite precursor solution. Among them, in the perovskite precursor solution, FA 0.9 Cs 0.1 The molar concentration of PbI3 is 1.5 mol / L.

[0119] The preparation steps of perovskite solar cells include:

[0120] (1) The ITO conductive glass was ultrasonically cleaned with glass cleaning liquid, deionized water, and ethanol for 20 min respectively, and finally dried in a drying oven at 75°C for later use; the dried ITO glass substrate was placed in a UV ozone machine for 20 min to remove organic impurities on its surface and optimize its surface wettability;

[0121] (2) In a nitrogen glove box, take 60 μL of perovskite precursor solution and spin coat it on the surface of the ITO substrate at a speed of 5000 rpm / min and an acceleration of 1000 rpm / s for 50 seconds. After completion, transfer it to an annealing hot plate and heat it at 100°C for 40 minutes to complete annealing; to form a 60nm hole transport layer and a 530nm perovskite film layer;

[0122] (3) 20 nm of C60 and 15 nm of BCP were sequentially deposited on the surface of the perovskite film layer as an electron transport layer;

[0123] (4) Evaporating 150 nm of Ag on the surface of the electron transport layer as an electrode layer to prepare a perovskite solar cell.

[0124] Example 3

[0125] Perovskite precursor solution: 0.96 g of perovskite precursor FA 0.9 Cs 0.1 PbI3 and 0.01g additive MACl were dissolved in 1mL of solvent with a volume ratio of DMF:NMP=4:1, and 0.5mg of thiocycloalkane P2 and 1.5mg of 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid as hole transport material were added, and stirred to dissolve to obtain a perovskite precursor solution. Among them, in the perovskite precursor solution, FA 0.9 Cs 0.1 The molar concentration of PbI3 is 1.5 mol / L.

[0126] The preparation steps of perovskite solar cells include:

[0127] (1) The ITO conductive glass was ultrasonically cleaned with glass cleaning liquid, deionized water, and ethanol for 20 min respectively, and finally dried in a drying oven at 75°C for later use; the dried ITO glass substrate was placed in a UV ozone machine for 20 min to remove organic impurities on its surface and optimize its surface wettability;

[0128] (2) In a nitrogen glove box, take 60 μL of the perovskite precursor solution and spin coat it on the surface of the ITO substrate at a speed of 5000 rpm / min and an acceleration of 1000 rpm / s for 50 seconds. After completion, transfer it to the annealing hot plate and heat it at 100°C for 40 minutes to complete annealing; to form a 60nm hole transport layer and a 500nm perovskite film layer;

[0129] (3) 20 nm of C60 and 15 nm of BCP were sequentially deposited on the surface of the perovskite film layer as an electron transport layer;

[0130] (4) Evaporating 150 nm of Ag on the surface of the electron transport layer as an electrode layer to prepare a perovskite solar cell.

[0131] Example 4

[0132] Perovskite precursor solution: 0.96 g of perovskite precursor FA 0.9 Cs 0.1 PbI3 and 0.01g additive MACl were dissolved in 1mL of solvent with a volume ratio of DMF:NMP=4:1, and 1mg of thiocycloalkane P2 and 1.5mg of 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid as hole transport material were added, and stirred to dissolve to obtain a perovskite precursor solution. Among them, in the perovskite precursor solution, FA 0.9 Cs 0.1 The molar concentration of PbI3 is 1.5 mol / L.

[0133] The preparation steps of perovskite solar cells include:

[0134] (1) The ITO conductive glass was ultrasonically cleaned with glass cleaning liquid, deionized water, and ethanol for 20 min respectively, and finally dried in a drying oven at 75°C for later use; the dried ITO glass substrate was placed in a UV ozone machine for 20 min to remove organic impurities on its surface and optimize its surface wettability;

[0135] (2) In a nitrogen glove box, take 60 μL of the perovskite precursor solution and spin coat it on the surface of the ITO substrate at a speed of 5000 rpm / min and an acceleration of 1000 rpm / s for 50 seconds. After completion, transfer it to the annealing hot plate and heat it at 100°C for 40 minutes to complete annealing; to form a 60nm hole transport layer and a 550nm perovskite film layer;

[0136] (3) 20 nm of C60 and 15 nm of BCP were sequentially deposited on the surface of the perovskite film layer as an electron transport layer;

[0137] (4) Evaporating 150 nm of Ag on the surface of the electron transport layer as an electrode layer to prepare a perovskite solar cell.

[0138] Example 5

[0139] Example 5 is basically the same as Example 1, the main difference being that the thiocycloalkane P1 is replaced by the thiocycloalkane P3 in the perovskite precursor solution of Example 5. The specific steps include:

[0140] Perovskite precursor solution: 0.96 g of perovskite precursor FA 0.9 Cs 0.1 PbI3 and 0.01g additive MACl were dissolved in 1mL of solvent with a volume ratio of DMF:NMP=4:1, and 0.5mg of thiocycloalkane P3 and 1.5mg of 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid as hole transport material were added, and stirred to dissolve to obtain a perovskite precursor solution. Among them, in the perovskite precursor solution, FA 0.9 Cs 0.1 The molar concentration of PbI3 is 1.5 mol / L.

[0141] Example 6

[0142] Example 6 is basically the same as Example 1, the main difference being that the thiocycloalkane P1 is replaced by the thiocycloalkane P4 in the perovskite precursor solution of Example 6. The specific steps include:

[0143] Perovskite precursor solution: 0.96 g of perovskite precursor FA 0.9 Cs 0.1 PbI3 and 0.01g additive MACl were dissolved in 1mL of solvent with a volume ratio of DMF:NMP=4:1, and 0.5mg of thiocycloalkane P4 and 1.5mg of 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid as hole transport material were added, and stirred to dissolve to obtain a perovskite precursor solution. Among them, in the perovskite precursor solution, FA 0.9 Cs 0.1 The molar concentration of PbI3 is 1.5 mol / L.

[0144] Comparative Example 1

[0145] Perovskite precursor solution: 0.96 g of perovskite precursor FA 0.9 Cs 0.1PbI3 and 0.01g additive MACl were dissolved in 1mL of solvent with a volume ratio of DMF:NMP=4:1, and 1.5mg of 4-(2,7-dibromo-9,9-dimethylacridine-10(9H)-yl)butyl)phosphonic acid was added as a hole transport material, and stirred to dissolve to obtain a perovskite precursor solution. Among them, in the perovskite precursor solution, FA 0.9 Cs 0.1 The molar concentration of PbI3 is 1.5 mol / L.

[0146] The preparation steps of perovskite solar cells include:

[0147] (1) The ITO conductive glass was ultrasonically cleaned with glass cleaning liquid, deionized water, and ethanol for 20 min respectively, and finally dried in a drying oven at 75°C for later use; the dried ITO glass substrate was placed in a UV ozone machine for 20 min to remove organic impurities on its surface and optimize its surface wettability;

[0148] (2) In a nitrogen glove box, take 60 μL of the perovskite precursor solution and spin coat it on the surface of the ITO substrate at a speed of 5000 rpm / min and an acceleration of 1000 rpm / s for 50 seconds. After completion, transfer it to the annealing hot stage and heat it at 100°C for 40 minutes to complete annealing; to form a 60nm hole transport layer and a 480nm perovskite film layer;

[0149] (3) 20 nm of C60 and 15 nm of BCP were sequentially deposited on the surface of the perovskite film layer as an electron transport layer;

[0150] (4) Evaporating 150 nm of Ag on the surface of the electron transport layer as an electrode layer to prepare a perovskite solar cell.

[0151] The above-mentioned perovskite solar cell is subjected to a performance test, and the test method includes:

[0152] (1) At a light intensity of 100 mW cm -2 Under the simulated sunlight AM1.5G irradiation condition, the JV curves of the perovskite solar cells of the above embodiments and comparative examples were tested; the corresponding test results are shown in FIG. Figure 2 At the same time, under this condition, the open circuit voltage (VOC), short circuit current (JSC), fill factor (FF), and photoelectric conversion efficiency (PCE) of the perovskite solar cell were measured, and the corresponding test results are shown in Table 1.

[0153] (2) The perovskite solar cells of the above-mentioned embodiment and comparative example were heated at a constant temperature of 100°C and 25% RH to test the thermal stability curve of the perovskite solar cells. The corresponding test results are shown in FIG. Figure 3 shown.

[0154] Table 1

[0155]

[0156] Depend on Figure 2 As shown in Table 1, the addition of thiocycloalkane to the precursor solution in the present embodiment can effectively improve the photoelectric conversion efficiency of the perovskite solar cell. In Example 1, the use of thiocycloalkane P1 can increase the PCE to 22.13%. In addition, the thermal stability curve of the perovskite solar cell shows that the PCE of the perovskite solar cell is 22.13%. Figure 3 It can be seen that the PCE of the battery device in Comparative Example 1, which did not add thiocycloalkanes as passivating agents, decayed by 48% after 100h and 100°C heating aging, the PCE of the battery device in Example 1 decayed by 37% after 100h and 100°C heating aging, the PCE of the battery device in Example 2 decayed by 43% after 100h and 100°C heating aging, the PCE of the battery device in Example 3 decayed by 31% after 100h and 100°C heating aging, and the PCE of the battery device in Example 4 decayed by 40% after 100h and 100°C heating aging. The PCE of the battery device in Example 5 decayed by 38% after 100h and 100°C heating aging. The PCE of the battery device in Example 6 decayed by 33% after 100h and 100°C heating aging. This shows that the addition of thiocycloalkanes to the precursor solution in the embodiments of the present application can effectively improve the thermal stability of the battery device.

[0157] 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.

[0158] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solution of the present application in detail, but it cannot be understood as limiting the scope of protection of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of this application shall be based on the content of the attached claims, and the description can be used to interpret the content of the claims.

Claims

1. A perovskite precursor solution, characterized in that: The perovskite precursor solution comprises a perovskite precursor, a solvent and a thiocycloalkane; the thiocycloalkane is selected from one or more compounds having structural characteristics shown in formula (I-1) to formula (I-3): , and ; x 11 and x 12 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 11 and x 12 At least one of them is S; y 11 and 12 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 11 and 12 At least one of them is C(=O); R1 and R2 are each independently H, substituted or unsubstituted C1~C6 alkyl; x 21 and x 22 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 21 and x 22 At least one of them is S; y 21 ,y 22 and 23 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 21 ,y 22 and 23 At least one of them is C(=O); x 31 、x 32 、x 33 and x 34 are each independently S, S(=O), S(=O)2, O, C(RR′) or N(R′′), and x 31 、x 32 、x 33 and x 34 At least one of them is S; y 31 and 32 are each independently C(RR′), C(═C), C(═O) or C(═S), and y 31 and 32 At least one of them is C(=O); Wherein, R, R′ and R′′ are each independently H, or a substituted or unsubstituted C1~C6 alkyl group.

2. The perovskite precursor solution according to claim 1, characterized in that x 11 and x 12 are each independently S, C(RR′) or N(R′′), and x 11 and x 12 At least one of them is S; y 11 and 12 are each independently C(RR′), C(═O) or C(═S), and y 11 and 12 At least one of them is C(=O); R1 and R2 are H, substituted or unsubstituted C1~C3 alkyl; x 21 and x 22 are each independently S, C(RR′) or N(R′′), and x 21 and x 22 At least one of them is S; y 21 ,y 22 and 23 are each independently C(RR′), C(═O) or C(═S), and y 21 ,y 22 and 23 At least one of them is C(=O); x 31 、x 32 、x 33 and x 34 are each independently S, C(RR′) or N(R′′), and x 31 、x 32 、x 33 and x 34 At least one of them is S; y 31 and 32 are each independently C(RR′), C(═O) or C(═S), and y 31 and 32 At least one of them is C(=O); Wherein, R, R′ and R′′ are each independently H, or a substituted or unsubstituted C1~C3 alkyl group.

3. The perovskite precursor solution according to claim 1, characterized in that The thiocycloalkane is selected from one or more compounds having structural features shown in formula (II-1) to formula (II-24): ； Wherein, R1 and R2 are H, substituted or unsubstituted C1~C6 alkyl; R, R' and R'' are each independently H, or a substituted or unsubstituted C1-C6 alkyl group.

4. The perovskite precursor solution according to claim 3, characterized in that The thiocycloalkane is selected from one or more compounds having structural features shown in formula (III-1) to formula (III-6): 。 5. The perovskite precursor solution according to any one of claims 1 to 4, characterized in that: The perovskite precursor solution has one or more of the following characteristics: (1) The mass ratio of the thiocycloalkane to the perovskite precursor is (0.0003-0.001): (0.9-2); (2) The concentration of the perovskite precursor in the perovskite precursor solution is 0.8 mol / L to 3 mol / L.

6. The perovskite precursor solution according to any one of claims 1 to 4, characterized in that: The perovskite precursor includes ABX3 material; Among them, A includes FA + 、MA + , Cs + , Rb + and K + One or more of, B includes Pb 2+ Sn 2+ and Ge 2+ One or more of, X is Cl - Br - and I - One or more of.

7. A method for preparing a perovskite film, characterized in that: The following steps are involved: The perovskite precursor film is formed on a substrate using the perovskite precursor solution according to any one of claims 1 to 6, and the perovskite precursor film is annealed to obtain the perovskite film.

8. A perovskite film, characterized in that: The thiocycloalkane is prepared by using the perovskite precursor solution according to any one of claims 1 to 6, or contains the thiocycloalkane in the perovskite precursor solution according to any one of claims 1 to 6.

9. The perovskite film according to claim 8, characterized in that: The perovskite film has one or more of the following characteristics: (1) The mass ratio of the thiocycloalkane to the perovskite precursor in the perovskite film is (0.0003-0.001): (0.9-2); (2) The thickness of the perovskite film is 300nm~1000nm.

10. A photovoltaic device, characterized in that: The photovoltaic device comprises a perovskite film, and the perovskite film is the perovskite film according to claim 8 or 9.

11. An electrical device, characterized in that: The photovoltaic device according to claim 10.

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