A type of tin-based perovskite material and its preparation method and application

Abstract

The present invention discloses a class of tin-based perovskite materials and their preparation methods and applications. The raw materials for preparing the tin-based perovskite materials of the present invention include sulfone additives and tin-containing raw materials, wherein the sulfone additives include at least one of bromodibenzothiophene 5,5-dioxide, tetrahydro-3-thiophenesulfonyl chloride 1,1-dioxide or 6-(trifluoromethyl)benzo[B]thiophene-3(2H)-ketone-1,1-dioxide. In the present invention, the sulfone additives can inhibit the growth of Sn in the tin-based perovskite. 2+ Oxidation, improving Sn 2+ The defects caused by oxidation and the antisite defects of Sn-I are eliminated, while the crystallization quality of the tin-based perovskite material is improved, and the quality of the tin-based perovskite material is high. The tin-based perovskite material of the present invention is applied to perovskite solar cells, and the photoelectric performance of the perovskite solar cells is significantly improved.

Description

Technical Field

[0001] The present invention belongs to the field of perovskite materials, and specifically relates to a class of tin-based perovskite materials and a preparation method and application thereof. Background Art

[0002] Compared to traditional crystalline silicon and inorganic thin-film solar cells, perovskite solar cells have been widely studied due to their simple preparation process and low cost. Currently, high-performance perovskite cells are typically developed based on lead-based perovskite materials. The presence of lead (Pb) can cause serious environmental pollution, hindering the industrialization of perovskite cells. Tin-based perovskite cells overcome this shortcoming, exhibiting higher charge mobility and a higher theoretical efficiency limit than lead-based perovskite materials. However, as the performance requirements for perovskite solar cells continue to increase, the photoelectric performance of conventional tin-based perovskite cells is increasingly unable to meet these demands. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention proposes a class of tin-based perovskite materials with good photoelectric properties.

[0004] The present invention also provides a method for preparing a tin-based perovskite material.

[0005] The present invention also provides a type of perovskite solar cell.

[0006] The present invention also provides a method for preparing a perovskite solar cell.

[0007] The present invention also provides a photoelectric device.

[0008] The present invention also proposes the application of the above-mentioned tin-based perovskite material.

[0009] In the first aspect of the present invention, a class of tin-based perovskite materials is proposed, the preparation raw materials of which include sulfone additives and tin-containing raw materials, and the sulfone additives include at least one of bromodibenzothiophene 5,5-dioxide, tetrahydro-3-thiophenesulfonyl chloride 1,1-dioxide or 6-(trifluoromethyl)benzo[B]thiophene-3(2H)-one-1,1-dioxide.

[0010] The tin-based perovskite material according to the embodiment of the present invention has at least the following beneficial effects:

[0011] Compared with the Sn in traditional tin-based perovskite materials 2+ The present invention adopts a small molecule additive - sulfone additive, which works synergistically with the tin-containing raw materials (especially the perovskite precursor) to improve the defects of tin-based perovskite materials: the addition of sulfone additives can inhibit the Sn in tin-based perovskite 2+Oxidation, improving Sn 2+ The defects caused by oxidation and the anti-site defects of Sn-I are eliminated, while the crystallization quality of the tin-based perovskite material is improved, and the quality of the tin-based perovskite material is high. The tin-based perovskite material of the present invention is applied to perovskite solar cells, and the photoelectric performance of the perovskite solar cells is significantly improved. The tin-based perovskite material of the present invention is applied to the preparation of electronic devices, which can improve the stability of the electronic devices. The tin-based perovskite material of the present invention has the prospect of being applied to other optoelectronic information functional materials, such as photodetectors, LED light-emitting devices, and field-effect transistors.

[0012] Moreover, the additive in the present invention is a small molecule type, and its small molecule configuration has better flexibility in regulating tin-based perovskite, can accurately passivate the internal defects of tin-based perovskite films, and can participate in the formation of tin-based perovskite lattices, thereby contributing to the stability of the tin-based perovskite lattices.

[0013] In some embodiments of the present invention, the brominated dibenzothiophene 5,5-dioxide includes at least one of 2,8-dibromodibenzothiophene 5,5-dioxide, 8-bromodibenzothiophene 5,5-dioxide, or 2-bromodibenzothiophene 5,5-dioxide.

[0014] According to the above embodiment, bromodibenzothiophene 5,5-dioxide has reducing properties and can react with Sn of tin-based perovskite. 2+ interaction, which can effectively inhibit the Sn 2+ The oxidation of tin-based perovskite can also regulate the crystallization dynamics of the growth of tin-based perovskite materials, improve the defects of difficult film formation, low efficiency and poor stability of tin-based perovskite films, and thus improve the stability and photoelectric performance of perovskite films. Specifically, for example, 2,8-dibromodibenzothiophene 5,5-dioxide, the Br and sulfoxide groups in its molecules can react with Sn in the perovskite. 2+ Strong interactions occur, and the molecules are also reducing, which can effectively inhibit the Sn in perovskite 2+ oxidation, improving the structure and photoelectric properties of tin-based perovskite.

[0015] Therefore, under the synergistic effect of bromodibenzothiophene 5,5-dioxide and tin-containing raw materials (such as perovskite precursor solution), the defects of tin-based perovskite films can be improved and the Sn 2+ oxidation.

[0016] In some embodiments of the present invention, the tin-containing raw material includes a perovskite precursor solution or a stannous halide material.

[0017] Through the above embodiment, under the synergistic effect of the sulfone additive (such as bromodibenzothiophene 5,5-dioxide) and the perovskite precursor solution, the defects of the tin-based perovskite film can be improved, and the Sn 2+ Specifically, in the preparation of tin-based perovskite material films, during the film formation process, sulfone additives as tin-based perovskite precursor solution additives can inhibit the oxidation of Sn in tin-based perovskite. 2+ The tin-based perovskite material of the present invention can be used to reduce oxidation and improve the crystallization quality of tin-based perovskite films, thereby solving the problems of difficult film formation and low efficiency of tin-based perovskite films. The tin-based perovskite material of the present invention can be applied to perovskite solar cells, significantly improving the photoelectric performance of the perovskite solar cells. The tin-based perovskite material of the present invention has the potential to be applied to other optoelectronic information functional materials, such as photodetectors, LED light-emitting devices, and field-effect transistors.

[0018] In some preferred embodiments of the present invention, the perovskite precursor solution includes a perovskite precursor component with a chemical composition of AB1Y1Y2Y3 or AB1B2Y1Y2Y3, wherein A is at least one of a formamidinium cation or a methylamine cation, B1 is a tin ion, B2 is a lead ion, and Y1, Y2, and Y3 are each independently selected from any one of an iodide ion, a bromide ion, and a chloride ion.

[0019] Through the above embodiment, the obtained perovskite material has excellent photoelectric conversion efficiency and low production cost. The perovskite precursor component (ABY1Y2Y3 or AB1B2Y1Y2Y3) and the sulfone additive synergistically act to further improve the MA or FA vacancy defects, Sn in the tin-based perovskite material film. 2+ The defects caused by oxidation and the effect of Sn-I antisite defects improve the stability and photoelectric properties of tin-based perovskite films.

[0020] In some more preferred embodiments of the present invention, the concentration of the perovskite precursor component in the perovskite precursor solution is 0.1-3 mol / L.

[0021] In some more preferred embodiments of the present invention, the concentration of the perovskite precursor component in the perovskite precursor solution is 0.6-1.6 mol / L.

[0022] In some preferred embodiments of the present invention, the molar ratio of the sulfone additive to the perovskite precursor component is (0.1-1.5):100.

[0023] In some preferred embodiments of the present invention, the perovskite precursor solution includes a perovskite precursor component and a precursor solvent.

[0024] In some more preferred embodiments of the present invention, the precursor solvent includes at least one of dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), N-methylpyrrolidone or γ-butyrolactone.

[0025] In some preferred embodiments of the present invention, the raw materials for preparing the perovskite precursor solution include stannous halide and formamidine amine halide (FAX).

[0026] In some more preferred embodiments of the present invention, the stannous halide comprises at least one of stannous iodide, stannous bromide or stannous fluoride.

[0027] In some more preferred embodiments of the present invention, the formamidine amine halide comprises formamidine amine iodide (FAI), which is also known as formamidine iodide.

[0028] In some preferred embodiments of the present invention, the tin-containing raw material is a stannous halide material, and the stannous halide material includes stannous iodide and stannous fluoride, and the preparation raw material further includes formamidine amine halide.

[0029] In some embodiments of the present invention, the tin-based perovskite material is a tin-based perovskite film.

[0030] In some embodiments of the present invention, the thickness of the tin-based perovskite material is 0.05-10 μm.

[0031] In some preferred embodiments of the present invention, the thickness of the tin-based perovskite material is 0.2-1 μm.

[0032] In some embodiments of the present invention, the particle size of the crystal grains contained in the tin-based perovskite material is 0.1-1 μm.

[0033] In some embodiments of the present invention, the roughness of the tin-based perovskite material is less than 50 nm.

[0034] In a second aspect of the present invention, a method for preparing a tin-based perovskite material is proposed, comprising the following steps: taking a tin-containing raw material and a sulfone additive, mixing them to obtain the tin-based perovskite material, wherein the tin-containing raw material includes a perovskite precursor solution or a stannous halide material.

[0035] The method for preparing the tin-based perovskite material according to the embodiment of the present invention has at least the following beneficial effects:

[0036] The present invention uses sulfone additives, which work synergistically with tin-containing raw materials (especially perovskite precursors) to improve the defects of tin-based perovskite materials. Sulfone additives have reducing properties and can react with the Sn of tin-based perovskites. 2+ interaction, which can effectively inhibit the Sn2+ At the same time, it can regulate the crystallization kinetics of the growth of tin-based perovskite materials, improve the crystallization quality of tin-based perovskite material films, and improve the defects of tin-based perovskite material films such as difficulty in film formation, low efficiency and poor stability, thereby improving the stability and photoelectric properties of tin-based perovskite materials.

[0037] The tin-based perovskite material of the present invention is applied to perovskite solar cells, which significantly improves the photoelectric performance of the perovskite solar cells. The tin-based perovskite material of the present invention is applied to the preparation of electronic devices, which can improve the stability of the electronic devices. The tin-based perovskite material of the present invention has the prospect of being applied to other optoelectronic information functional materials, such as photodetectors, LED light-emitting devices, and field-effect transistors.

[0038] In some embodiments of the present invention, the perovskite precursor solution includes a perovskite precursor component, and the concentration of the perovskite precursor component in the perovskite precursor solution is 0.1-3 mol / L.

[0039] In some preferred embodiments of the present invention, the concentration of the perovskite precursor component in the perovskite precursor solution is 0.6-1.6 mol / L.

[0040] Through the above embodiment, the concentration of the perovskite precursor component is 0.6-1.6 mol / L, which can make the sulfone additive (such as bromodibenzothiophene 5,5-dioxide) and the hybrid perovskite material of ABY1Y2Y3 or AB1B2Y1Y2Y3 highly dispersed in the solvent, so that the mixed solution of the perovskite precursor solution and the sulfone additive can be subsequently subjected to film formation treatment.

[0041] In some embodiments of the present invention, the tin-based perovskite material is a tin-based perovskite material film, and the preparation method of the film comprises the following steps:

[0042] S1, mixing a perovskite precursor solution and a sulfone additive to obtain a mixture, and performing spin coating using an antisolvent to obtain a wet film;

[0043] S2, annealing the wet film to obtain the tin-based perovskite material.

[0044] Through the above-mentioned embodiment, the present invention provides a method for preparing tin-based perovskite materials by using sulfone additives to assist film formation. A mixture of a sulfone additive (such as bromodibenzothiophene 5,5-dioxide) and a tin-based perovskite precursor solution is treated with an anti-solvent to form a wet film, thereby forming a tin-based perovskite film. The wet film is annealed to form a tin-based perovskite film, wherein the sulfone additive (such as bromodibenzothiophene 5,5-dioxide) has reducing properties and can react with the Sn of the tin-based perovskite. 2+interaction, which can effectively inhibit the Sn 2+ At the same time, it can regulate the crystallization kinetics of the growth of tin-based perovskite films, improve the defects of tin-based perovskite films such as difficult film formation, low efficiency and poor stability, and thus improve the stability and photoelectric properties of tin-based perovskite films.

[0045] In some preferred embodiments of the present invention, in step S1, in the mixture, the molar ratio of the sulfone additive to the perovskite precursor component is (0.1-1.5):100.

[0046] In some preferred embodiments of the present invention, in step S1, the antisolvent in the antisolvent spin coating process includes at least one of chlorobenzene, diethyl ether or toluene.

[0047] In some preferred embodiments of the present invention, in step S1, the mixture is spin-coated with an anti-solvent to form a wet film on the surface of the substrate.

[0048] In some more preferred embodiments of the present invention, in step S1, the mixture is spin-coated on the surface of the substrate, and an anti-solvent is added during the spin-coating to obtain a wet film.

[0049] In some more preferred embodiments of the present invention, in the anti-solvent spin coating process of step S1, the spin coating speed is 2000-5000 rpm, and the spin coating time is 30-60 s.

[0050] In some preferred embodiments of the present invention, in step S1, the mass ratio of the mixture to the anti-solvent is (1-10):1.

[0051] The present invention prepares a high-quality perovskite film layer through anti-solvent spin coating, that is, a one-step anti-solvent film formation method, which can be an organic-inorganic hybrid perovskite film layer.

[0052] In some preferred embodiments of the present invention, in step S2, the annealing temperature is 50-250°C.

[0053] In some preferred embodiments of the present invention, in step S2, the annealing time is 5-90 min.

[0054] In some embodiments of the present invention, the preparation method further includes preparing a perovskite precursor solution, which specifically includes the following operations: mixing stannous halide, formamidine halide, and a precursor solvent to obtain the perovskite precursor solution.

[0055] In some preferred embodiments of the present invention, the preparation of the perovskite precursor solution specifically includes the following operations: mixing formamidinium iodide, stannous iodide, stannous fluoride and a precursor solvent to obtain the perovskite precursor solution.

[0056] In some more preferred embodiments of the present invention, the molar ratio of formamidine iodide, stannous iodide and stannous fluoride is (0.8-1.2):(0.8-1.2):(0.02-0.2).

[0057] In some preferred embodiments of the present invention, the precursor solvent includes at least one of dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), N-methylpyrrolidone or γ-butyrolactone.

[0058] In some preferred embodiments of the present invention, the precursor solvent includes DMF and DMSO, and the volume ratio of DMF to DMSO is (2-6):1.

[0059] In some embodiments of the present invention, the tin-containing raw material is a stannous halide material, and the stannous halide material includes stannous iodide and stannous bromide. The preparation method of the tin-based perovskite material includes the following steps: mixing a sulfone additive, stannous iodide, stannous fluoride, formamidine ammonium iodide and a precursor solvent to obtain a mixture, coating the mixture on a substrate, and annealing to obtain the tin-based perovskite material.

[0060] In a third aspect of the present invention, a perovskite solar cell is provided, comprising the tin-based perovskite material according to any one of the first and second aspects of the present invention.

[0061] In some embodiments of the present invention, the perovskite solar cell includes a perovskite light-absorbing layer, and the perovskite light-absorbing layer includes the tin-based perovskite material according to any one of the first and second aspects of the present invention.

[0062] Perovskite solar cells according to embodiments of the present invention have at least the following beneficial effects: The perovskite light-absorbing layer employed in the present invention, with the addition of a sulfone additive, significantly improves the quality of the perovskite light-absorbing layer, resulting in excellent stability and photoelectric performance. Application of the perovskite light-absorbing layer in a perovskite solar cell can improve the photoelectric performance and service life of the solar cell.

[0063] In some embodiments of the present invention, the thickness of the perovskite light absorbing layer is 0.05-10 μm.

[0064] In some preferred embodiments of the present invention, the thickness of the perovskite light absorbing layer is 0.2-1 μm.

[0065] In some embodiments of the present invention, the perovskite solar cell further comprises one or more electronic functional layers stacked with the perovskite light absorbing layer.

[0066] In some preferred embodiments of the present invention, the electronic functional layer includes a hole transport layer, and the hole transport layer is provided on the surface of the perovskite light absorbing layer.

[0067] In some more preferred embodiments of the present invention, the hole transport layer includes poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(styrene sulfonate) (PSS).

[0068] In some more preferred embodiments of the present invention, the hole transport layer is formed of a material containing PEDOT:PSS.

[0069] In some more preferred embodiments of the present invention, the method for preparing the hole transport layer comprises the following operations: taking a PEDOT:PSS solution, coating, and annealing to obtain the hole transport layer.

[0070] In some more preferred embodiments of the present invention, the hole transport layer has a thickness of 0.01-0.5 μm.

[0071] In some preferred embodiments of the present invention, the electronic functional layer further includes a conductive substrate, and the hole transport layer is located between the conductive substrate and the perovskite light absorbing layer.

[0072] In some more preferred embodiments of the present invention, the conductive substrate comprises a substrate and a conductive layer, wherein the conductive layer is located between the substrate and the hole transport layer.

[0073] In some more preferred embodiments of the present invention, the conductive substrate includes a glass substrate and an indium tin oxide (ITO) layer.

[0074] In some more preferred embodiments of the present invention, the conductive substrate comprises a glass substrate on which ITO is deposited.

[0075] In some preferred embodiments of the present invention, the perovskite solar cell includes a conductive substrate, a hole transport layer, and a perovskite light absorbing layer stacked in sequence.

[0076] In some preferred embodiments of the present invention, the electronic functional layer further includes an electron transport layer, and the electron transport layer is provided on a side of the perovskite light absorbing layer away from the hole transport layer.

[0077] In some more preferred embodiments of the present invention, the electron transport layer comprises fullerene (C 60 )layer.

[0078] In some more preferred embodiments of the present invention, the fullerene layer is formed of a material containing fullerene.

[0079] In some more preferred embodiments of the present invention, the thickness of the fullerene layer is 10-100 nm.

[0080] In some more preferred embodiments of the present invention, the method for preparing the fullerene layer comprises the following operations: -5 Pa under the condition of fullerene is deposited by thermal evaporation to obtain the fullerene layer.

[0081] In some more preferred embodiments of the present invention, the electron transport layer further includes an interface modification layer, and the fullerene layer is located between the interface modification layer and the perovskite light absorption layer.

[0082] In some more preferred embodiments of the present invention, the interface modification layer includes dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP).

[0083] In some more preferred embodiments of the present invention, the interface modification layer is formed of a material containing dimethyl-4,7-diphenyl-1,10-phenanthroline.

[0084] In some more preferred embodiments of the present invention, the method for preparing the interface modification layer comprises the following operations: -5 Pa under the condition of thermal evaporation to deposit BCP, thereby obtaining the interface modification layer.

[0085] In some more preferred embodiments of the present invention, the thickness of the interface modification layer is 1-20 nm.

[0086] In some preferred embodiments of the present invention, the electronic functional layer further includes an electrode, and the electron transport layer is located between the electrode and the perovskite light absorbing layer.

[0087] In some more preferred embodiments of the present invention, the electrode comprises a metal electrode. Preferably, the metal electrode comprises at least one of copper, gold or silver.

[0088] In some more preferred embodiments of the present invention, the metal electrode is formed of a material containing Cu and / or Ag.

[0089] In some more preferred embodiments of the present invention, the method for preparing the metal electrode comprises the following steps: -5 Pa by thermal evaporation deposition to obtain the metal electrode.

[0090] In some more preferred embodiments of the present invention, the thickness of the electrode is 40-200 nm.

[0091] In some more preferred embodiments of the present invention, the thickness of the electrode is 80-120 nm. In some preferred embodiments of the present invention, the perovskite solar cell includes a conductive substrate, a hole transport layer, a perovskite light absorbing layer, an electron transport layer and an electrode stacked in sequence.

[0092] In a fourth aspect of the present invention, a method for preparing a type of perovskite solar cell is proposed, comprising the following steps: sequentially preparing a hole transport layer and a perovskite light absorption layer on the surface of the conductive substrate to obtain the perovskite solar cell.

[0093] In some embodiments of the present invention, the preparation method comprises the following steps:

[0094] Sc-1, preparation of a hole transport layer on the surface of a conductive substrate;

[0095] Sc-2, a perovskite light-absorbing layer is prepared on the surface of the hole transport layer.

[0096] In some preferred embodiments of the present invention, in step Sc-1, the conductive substrate is a glass substrate deposited with ITO, and before preparing the hole transport layer, the glass substrate deposited with ITO is pre-treated.

[0097] In some more preferred embodiments of the present invention, the pre-treatment method of the glass substrate deposited with ITO includes the following operations: performing continuous multi-step ultrasonic cleaning on the glass substrate deposited with ITO, including ultrasonic cleaning with detergent, deionized water, acetone, and ethanol in sequence, and drying after ultrasonic cleaning.

[0098] In some more preferred embodiments of the present invention, the glass substrate deposited with ITO needs to be irradiated with ultraviolet light before use.

[0099] In some preferred embodiments of the present invention, in step Sc-1, a PEDOT:PSS solution is coated on a conductive substrate and annealed to prepare a hole transport layer.

[0100] In some more preferred embodiments of the present invention, in step Sc-1, the annealing temperature is 80-200° C., and the annealing time is 5-60 min.

[0101] In some more preferred embodiments of the present invention, in step Sc-1, the PEDOT:PSS solution is filtered, spin-coated on a conductive substrate, and annealed to prepare a hole transport layer.

[0102] In step Sc-1, the spin coating speed is 2000-8000 rpm, and the spin coating time is 10-120 s.

[0103] In some preferred embodiments of the present invention, the preparation method further comprises step Sc-3, preparing an electron transport layer on the surface of the perovskite light absorbing layer.

[0104] In some more preferred embodiments of the present invention, in step Sc-3, on the surface of the perovskite light absorbing layer, the vacuum degree is less than 10 -5 The electron transport layer was prepared by depositing a fullerene layer and a BCP layer at once by thermal evaporation under Pa conditions.

[0105] In some preferred embodiments of the present invention, the preparation method further comprises step Sc-4, preparing an electrode on the surface of the electron transport layer.

[0106] In some more preferred embodiments of the present invention, in step Sc-4, the electrode is a metal electrode, and the preparation method of the metal electrode comprises the following operations: on the surface of the electron transport layer, at a vacuum degree of <10 -5 The metal electrode was prepared by thermal evaporation deposition under the conditions of Pa.

[0107] In a fifth aspect of the present invention, a photoelectric device is provided, comprising the above-mentioned tin-based perovskite material.

[0108] In some embodiments of the present invention, the optoelectronic device includes at least one of a solar cell, a photodetector, an LED light emitting device, or a field effect transistor.

[0109] The sixth aspect of the present invention proposes the use of the above-mentioned tin-based perovskite material in the preparation of optoelectronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0110] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0111] Figure 1 Schematic diagram of the structure of the perovskite solar cell in Example 1 of the present invention;

[0112] Figure 2 Schematic diagram of the structural components of the perovskite solar cell in Example 1 of the present invention;

[0113] Figure 3 Graph showing the atomic force microscope test results of the tin-based perovskite film in Comparative Example 1;

[0114] Figure 4 This is a diagram showing the atomic force microscope test results of the tin-based perovskite film in Example 1 of the present invention;

[0115] Figure 5 This is a scanning electron microscope test result diagram of the tin-based perovskite film in Comparative Example 1;

[0116] Figure 6This is a scanning electron microscope test result diagram of the tin-based perovskite film in Example 1 of the present invention;

[0117] Figure 7 1 is a particle size distribution diagram of the crystal grains contained in the tin-based perovskite film in Comparative Example 1;

[0118] Figure 8 This is a diagram showing the particle size distribution of the crystal grains contained in the tin-based perovskite film in Example 1 of the present invention. DETAILED DESCRIPTION

[0119] The following will clearly and completely describe the concept and technical effects of the present invention in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0120] The experimental methods in the following examples, for which specific conditions are not specified, are generally performed in accordance with conventional conditions in the art or conditions recommended by the manufacturers; the raw materials and reagents used, unless otherwise specified, are all commercially available from conventional markets.

[0121] Example 1

[0122] This embodiment discloses a tin-based perovskite material, which is a tin-based perovskite film with a thickness of 0.3 μm, a grain size of 0.1-1 μm, and a roughness of less than 50 nm. The preparation process includes:

[0123] (1) Formamidinium iodide (FAI), stannous iodide (SnI2), and stannous fluoride (SnF2) were weighed in a glove box at a molar ratio of 1:1:0.1 and dissolved in a DMF / DMSO (DMF / DMSO volume ratio is 4:1) mixed solution to obtain a 1 mol / L concentration of a FASnI3 perovskite precursor solution (referred to as precursor solution I). (In other embodiments of the present invention, the concentration of the FASnI3 perovskite precursor in precursor solution I can be 0.6-1.6 mol / L.)

[0124] (2) 2,8-dibromodibenzothiophene 5,5-dioxide is doped into precursor solution I in a certain proportion to obtain a tin-based perovskite precursor solution containing 2,8-dibromodibenzothiophene 5,5-dioxide (referred to as precursor solution II), wherein in precursor solution II: based on the mass of precursor solution I being 100%, the amount of 2,8-dibromodibenzothiophene 5,5-dioxide added is 0.8%. (In other embodiments of the present invention, the amount of 2,8-dibromodibenzothiophene 5,5-dioxide added may be 0.1-1.5%).

[0125] (3) Precursor solution II is dropped onto the substrate, assisted by spin coating conditions of 3000-5000 rpm for 30-60 seconds, and 150 μL of chlorobenzene is added as an anti-solvent to form a thin wet film on the substrate surface. The substrate is a PEDOT:PSS layer formed by a PEDOT:PSS solution. The PEDOT:PSS solution is a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) solution purchased from Xi'an Baolait Optoelectronics Technology Co., Ltd., PEDOT:PSS (4083), J1104, with a concentration of 1.3-1.7% aqueous solution.

[0126] (4) The substrate and the thin wet film on its surface were annealed at 80°C for 10 min to obtain a stacked PEDOT:PSS layer and a tin-based perovskite film.

[0127] This embodiment also discloses a perovskite solar cell, the structural diagram and structural component diagram of which are as follows: Figure 1-2 As shown, it includes a conductive substrate (a glass plate with ITO deposited, ITO is used as an anode), a hole transport layer (PEDOT:PSS), a perovskite light absorbing layer, an electron transport layer (including C 60 layer and BCP interface modification layer), cathode (metal electrode Ag), wherein the perovskite light absorbing layer is the tin-based perovskite film of this embodiment. The preparation process of the perovskite solar cell in this embodiment includes:

[0128] (I) Treating a glass substrate deposited with ITO (hereinafter referred to as an ITO glass substrate) includes: performing a continuous multi-step ultrasonic cleaning of the ITO glass substrate, sequentially adding a detergent, deionized water, acetone, and ethanol to each ultrasonic cleaning tank; drying the ITO glass substrate after ultrasonic cleaning; and irradiating the cleaned ITO glass substrate with a UV lamp. The ITO glass substrate has a transmittance of 90% and an impedance of 7 ohms, and is purchased from Youxuan, model 1.1 mm 7 ohms. The cleaning agent is a glass cleaning agent purchased from Guangzhou Daily Chemical, specification 12basic.

[0129] (II) Preparation of a PEDOT:PSS hole transport layer, comprising: filtering a PEDOT:PSS solution, coating it on an ITO glass substrate by spin coating at 5000 rpm for 30 seconds, and then annealing it on a hot plate at 140°C for 15 minutes to obtain a PEDOT:PSS hole transport layer (thickness approximately 50 nm). The PEDOT:PSS solution is the same as the PEDOT:PSS solution in step (3) of this embodiment.

[0130] (III) Preparation of a perovskite light absorbing layer (tin-based perovskite film), comprising: using a PEDOT:PSS hole transport layer as a substrate, and preparing a 0.3 μm thick tin-based perovskite film on the surface of the PEDOT:PSS hole transport layer. The specific preparation steps are the same as steps (1) to (4) in this embodiment.

[0131] (IV) Preparation of electron transport layer, including: on the surface of perovskite light absorbing layer, in a vacuum degree <10 -5 The fullerene layer and the BCP interface modification layer were sequentially deposited by thermal evaporation under the conditions of Pa, with thicknesses of 40 nm and 8 nm, respectively.

[0132] (V) Preparation of metal electrodes, including: on the surface of the BCP interface modification layer, in a vacuum degree <10 -5 Ag was deposited by thermal evaporation under Pa conditions to a thickness of 100 nm (the thickness could be 80-120 nm).

[0133] The thickness of the tin-based perovskite film in this embodiment is 0.3 μm, which is a moderate thickness. The roughness of the tin-based perovskite film is less than 50 nm, and the flatness is relatively high.

[0134] This embodiment also discloses a photoelectric device, which is a photodetector, comprising the tin-based perovskite material prepared in this embodiment.

[0135] Example 2

[0136] This embodiment discloses a perovskite solar cell, which differs from the embodiment 1 only in that Cu is used in the cathode of the battery of this embodiment to replace the Ag in the embodiment 1.

[0137] Example 3

[0138] This embodiment discloses a tin-based perovskite material, which is a tin-based perovskite film with a thickness of 0.3 μm. The only difference between it and Example 1 is that this embodiment uses 2-bromodibenzothiophene 5,5-dioxide in the same amount of substance instead of 2,8-dibromodibenzothiophene 5,5-dioxide in Example 1.

[0139] This embodiment also discloses a perovskite solar cell, which differs from Example 1 only in that in the preparation of the perovskite light-absorbing layer of the cell described in this embodiment, 2-bromodibenzothiophene 5,5-dioxide is used in the same amount of substance instead of 2,8-dibromodibenzothiophene 5,5-dioxide in Example 1.

[0140] This embodiment also discloses a photoelectric device, which is a photodetector, comprising the tin-based perovskite material prepared in this embodiment.

[0141] Example 4

[0142] This embodiment discloses a perovskite solar cell, which differs from the embodiment 3 only in that Cu is used in the cathode of the battery of this embodiment to replace the Ag in the embodiment 3.

[0143] Example 5

[0144] This embodiment discloses a tin-based perovskite material, which is a tin-based perovskite film with a thickness of 0.3 μm. The only difference between it and Example 1 is that this embodiment uses 8-bromodibenzothiophene 5,5-dioxide in the same amount of substance instead of 2,8-dibromodibenzothiophene 5,5-dioxide in Example 1.

[0145] This embodiment also discloses a perovskite solar cell, which differs from Example 1 only in that in the preparation of the perovskite light-absorbing layer of the cell described in this embodiment, 8-bromodibenzothiophene 5,5-dioxide is used in the same amount of substance instead of 2,8-dibromodibenzothiophene 5,5-dioxide in Example 1.

[0146] This embodiment also discloses a photoelectric device, which is a photodetector, comprising the tin-based perovskite material prepared in this embodiment.

[0147] Example 6

[0148] This embodiment discloses a perovskite solar cell, which differs from the embodiment 5 only in that Cu is used in the cathode of the battery of this embodiment to replace the Ag in the embodiment 5.

[0149] Comparative Example 1

[0150] This comparative example discloses a tin-based perovskite material, which is a tin-based perovskite film. The only difference between it and Example 1 is that in this comparative example, 2,8-dibromodibenzothiophene 5,5-dioxide is not added to the precursor solution I. That is, in this comparative example, the precursor solution I is dropped onto the surface of the substrate to form a tin-based perovskite film.

[0151] This comparative example discloses a perovskite solar cell, which differs from Example 1 only in that: during the preparation of the perovskite light-absorbing layer of the battery described in this comparative example, 2,8-dibromodibenzothiophene 5,5-dioxide is not added to the precursor solution I, that is, in this comparative example, the precursor solution I is dropped onto the surface of the hole transport layer (PEDOT:PSS) to form a tin-based perovskite film with a thickness of 0.3 μm to obtain the perovskite light-absorbing layer.

[0152] Test example

[0153] This test example tests the performance of the tin-based perovskite materials and perovskite solar cells obtained in the examples and comparative examples, specifically including:

[0154] (1) Microscopic testing was performed on the tin-based perovskite films obtained in Example 1 and Comparative Example 1, specifically including: Atomic force microscope images of the tin-based perovskite films of Comparative Example 1 and Example 1 are shown in FIG. Figure 3-4 The scanning electron microscope images of the tin-based perovskite film of Comparative Example 1 and Example 1 are as follows: Figure 5-6 The particle size distribution diagrams of the tin-based perovskite film of Comparative Example 1 and Example 1 are as follows: Figure 7-8 .

[0155] Depend on Figure 3-8 It can be seen that the tin-based perovskite film prepared by the present invention contains crystal grains with a particle size of 0.1-1 μm, and the crystal grains are relatively uniform. The film has low roughness and high flatness.

[0156] (2) Photovoltaic performance testing of perovskite solar cells, specifically including the following steps:

[0157] The battery's current density-voltage (JV) characteristic curve was tested under an AM1.5G 100 mW / cm² simulated light source (Enlitech Solar Simulator SS-F5-3A). The measurements were performed in a nitrogen-filled glove box, unencapsulated, using a computer-controlled Keithley 2400 source-measurement unit. The external quantum efficiency (EQE) was measured at room temperature in air (40% humidity), unencapsulated, using a DSR100UV-B spectrometer equipped with an SR830 lock-in amplifier, using a bromine tungsten lamp as the light source.

[0158] The test results of the current density-voltage characteristic curves of the perovskite solar cells provided in Examples 1, 3, 5 and Comparative Example 1 are shown in Table 1 below.

[0159] Table 1

[0160]

[0161] As shown in Table 1, compared with other examples, the tin-based perovskite solar cell with the 2,8-dibromodibenzothiophene 5,5-dioxide additive as the auxiliary film has the best photoelectric performance, with an open circuit voltage of 0.86 V and a current of 22.19 mA / cm 2 The short-circuit current density, fill factor of 72.20% and photoelectric conversion efficiency of 13.78% are significantly improved compared with the device efficiency prepared by the comparative example without additive-assisted film formation method.

[0162] In traditional tin-based perovskite materials, Sn 2+ Easy oxidation can lead to instability of tin-based perovskite devices and seriously affect the photoelectric conversion efficiency of the devices.

[0163] The tin-based perovskite film provided by the present invention is formed on a substrate by a mixed solution of bromine-containing dibenzothiophene 5,5-dioxide and a perovskite precursor solution to obtain a tin-based perovskite film bonded to the substrate surface. Under the synergistic effect of bromine-containing dibenzothiophene 5,5-dioxide and the perovskite precursor solution, the defects of the tin-based perovskite film can be improved. Compared with the existing tin-based perovskite film, the MA or FA vacancy defects, Sn 2+ The defects caused by oxidation, the anti-site defects of Sn-I, can improve the stability of electronic devices if the tin-based perovskite film can be used to prepare electronic devices. Therefore, the tin-based perovskite film of the present invention has the prospect of being applied to other optoelectronic information functional materials, such as photodetectors, LED light-emitting devices and field-effect transistors. In addition, in the process of film formation of the mixed solution of the perovskite precursor solution, bromodibenzothiophene 5,5-dioxide is used as an additive to the perovskite precursor solution to inhibit the Sn in the tin-based perovskite. 2+ The oxidation of tin-based perovskite films can improve the crystallization quality of the films, thereby solving the problems of difficult film formation and low efficiency of tin-based perovskite films. Specifically, bromodibenzothiophene 5,5-dioxide has a reducing property and can react with Sn of tin-based perovskite. 2+ interaction, which can effectively inhibit the Sn 2+ The present invention can simultaneously regulate the crystallization kinetics of tin-based perovskite film growth, improving the defects of difficult film formation, low efficiency, and poor stability of tin-based perovskite films, thereby improving the stability and photoelectric performance of the perovskite films. The present invention solves the problem that existing tin-based perovskite films have poor stability and traditional tin-based perovskite film preparation methods lack effective control over the tin-based perovskite film formation process, resulting in a large number of defects in the prepared tin-based perovskite films.

[0164] In this invention, bromodibenzothiophene 5,5-dioxide is used as an additive to assist in the growth of high-quality tin-based perovskite thin films, which are applied to perovskite solar cells to improve the photovoltaic performance and service life of the solar cells. Furthermore, based on a rational cell device structure, a complete solar cell device is constructed by combining a conductive substrate, a hole transport layer, an electron transport layer, and metal electrodes. The resulting solar cell can achieve a photoelectric conversion efficiency exceeding 13% while exhibiting good stability, providing a technical foundation for future commercial development.

[0165] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. A tin-based perovskite material, characterized in that: The preparation raw materials include sulfone additives and tin-containing raw materials, wherein the sulfone additives include at least one of bromodibenzothiophene 5,5-dioxide, tetrahydro-3-thiophenesulfonyl chloride 1,1-dioxide or 6-(trifluoromethyl)benzo[B]thiophene-3(2H)-one-1,1-dioxide; the tin-containing raw material is a perovskite precursor solution, and the perovskite precursor solution includes a perovskite precursor component with a chemical composition of AB1Y1Y2Y3 or AB1B2Y1Y2Y3, wherein A is at least one of a formamidinium cation or a methylamine cation, B1 is a tin ion, B2 is a lead ion, and Y1, Y2 and Y3 are each independently selected from any one of an iodide ion, a bromide ion and a chloride ion.

2. The tin-based perovskite material according to claim 1, characterized in that In the perovskite precursor solution, the concentration of the perovskite precursor component is 0.1-3 mol / L.

3. The tin-based perovskite material according to claim 1, characterized in that The molar ratio of the sulfone additive to the perovskite precursor component is (0.1-1.5):

100.

4. The tin-based perovskite material according to claim 1, characterized in that The thickness of the tin-based perovskite material is 0.05-10 μm.

5. A method for preparing the tin-based perovskite material according to any one of claims 1, characterized in that: The method comprises the following steps: taking a tin-containing raw material and a sulfone additive, mixing them, and obtaining the tin-based perovskite material.

6. The method for preparing the tin-based perovskite material according to claim 5, characterized in that: The tin-based perovskite material is a tin-based perovskite material film, and the preparation method of the film comprises the following steps: S1, mixing a perovskite precursor solution and a sulfone additive to obtain a mixture, and performing spin coating using an antisolvent to obtain a wet film; S2, annealing the wet film to obtain the tin-based perovskite material.

7. A perovskite solar cell, characterized in that The tin-based perovskite material comprises the tin-based perovskite material according to any one of claims 1 to 4.

8. A photoelectric device, characterized in that: The tin-based perovskite material comprises the tin-based perovskite material according to any one of claims 1 to 4.

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