Low-dimensional layered wide-band-gap perovskite material, wide-band-gap perovskite solar cell and preparation method of low-dimensional layered wide-band-gap perovskite material

Abstract

The invention discloses a low-dimensional layered wide-band-gap perovskite material, a wide-band-gap perovskite solar cell and a preparation method of the low-dimensional layered wide-band-gap perovskite material, the chemical formula of the low-dimensional layered wide-band-gap perovskite material is A2Bn-1PbnX3n + 1, A is at least one of 4-fluoro-phenethylammonium ions, phenethylammonium ions, butylammonium ions and octyl ammonium ions, Pb is at least one of 4-fluoro-phenethylammonium ions, Pb is at least one of 4-fluoro-phenethylammonium ions, Pb is at least one of 4-fluoro-phenethylammonium ions, Pb is at least one of 4-fluoro- B is at least one of methylamine ions, formamidine ions and cesium ions, X is at least one halide ion, and n is larger than 1 and smaller than 10. The low-dimensional layered wide-band-gap perovskite material provided by the invention has excellent environmental stability, the band gap can reach 1.70 eV, the open-circuit voltage of a perovskite solar cell based on the low-dimensional layered wide-band-gap perovskite material can reach 1.27 V, the photoelectric conversion efficiency of 20.18% can be obtained under the effective area of 0.1 cm < 2 >, and the low-dimensional layered wide-band-gap perovskite material has relatively good stability.

Description

Technical Field

[0001] The present invention relates to the technical field of perovskite materials, and in particular to a low-dimensional layered wide-bandgap perovskite material, a wide-bandgap perovskite solar cell and a preparation method thereof. Background Art

[0002] Inorganic-organic perovskite materials have attracted much attention due to their excellent energy conversion efficiency and adjustable band gap. Wide-bandgap cells absorb short-wavelength light, while narrow-bandgap cells absorb long-wavelength light. Among them, hybrid halide perovskite cells with a band gap > 1.65 eV are usually defined as wide-bandgap perovskite cells.

[0003] In order to meet the requirements of different bandgap ranges, introducing bromide mixed with iodide is a common strategy for wide bandgap perovskite films. A larger bromide-to-iodine ratio naturally leads to phase separation, which has been considered to be the main cause of photoinduced instability. On the other hand, compared with ordinary bandgap perovskite solar cells, wide bandgap perovskite solar cells suffer from more severe open circuit voltage losses. To improve the relevant performance, one way to achieve this goal is to form a two-dimensional / three-dimensional perovskite heterojunction.

[0004] This strategy can be roughly divided into two categories. One is to add long-chain molecules to the surface passivator to construct a two-dimensional / three-dimensional heterostructure at the interface. The other is to use a small amount of long-chain molecules as bulk additives to form a small amount of two-dimensional / three-dimensional heterostructure at the bulk grain boundary. Long-chain molecules can hinder ion migration and inhibit charge recombination, improving the stability of the battery, but they will also hinder the transport of carriers, thereby reducing the performance of the battery. Therefore, it is difficult for existing solutions to simultaneously achieve the goals of efficiency and stability of wide-bandgap perovskite solar cells.

[0005] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0006] Based on the above-mentioned deficiencies of the prior art, the object of the present invention is to provide a low-dimensional layered wide-bandgap perovskite material, a wide-bandgap perovskite solar cell and a preparation method thereof, aiming to solve the problem that the existing wide-bandgap perovskite solar cells cannot have good efficiency and stability at the same time.

[0007] The technical solution of the present invention is as follows:

[0008] In a first aspect of the present invention, a low-dimensional layered wide band gap perovskite material is provided, wherein the chemical formula of the low-dimensional layered wide band gap perovskite material is A2B n-1 Pb n X 3n+1, wherein A is at least one of 4-fluoro-phenethylammonium ion, phenethylammonium ion, butylammonium ion, and octylammonium ion, B is at least one of methylamine ion, formamidine ion, and cesium ion, X is at least one halogen ion, and the value of n is greater than 1 and less than 10.

[0009] Optionally, the low-dimensional layered wide bandgap perovskite material is in powder form or thin film form.

[0010] Optionally, the chemical formula of the low-dimensional layered wide bandgap perovskite material is (4F-PEA)2(FA 0.73 Cs 0.27 ) 5.5 Pb 6.5 (I 0.78 Br 0.22 ) 20.5 , 4F-PEA is 4-fluoro-phenethylammonium ion, and FA is formamidinium ion.

[0011] A second aspect of the present invention provides a method for preparing the low-dimensional layered wide bandgap perovskite material as described above, comprising the following steps:

[0012] Press A2B n-1 Pb n X 3n+1 The stoichiometric ratio of each element in the mixture is adjusted, and AI, BX and PbX are added to an organic solvent for mixing or ABr, BX and PbX are added to an organic solvent for mixing to obtain a precursor solution; wherein AI is at least one of 4-fluoro-phenethylammonium iodide, phenethylammonium iodide, butylammonium iodide, and octylammonium iodide; ABr is at least one of 4-fluoro-phenethylammonium bromide and phenethylammonium bromide; BX is at least one of methylamine halide, formamidine halide, and cesium halide; and PbX is at least one lead halide;

[0013] After the precursor solution is reacted, a low-dimensional layered wide band gap perovskite material in powder form is obtained; or, after the perovskite precursor solution is coated and annealed, a low-dimensional layered wide band gap perovskite material in film form is obtained.

[0014] Optionally, the annealing temperature is 105-120° C., and the annealing time is 20-40 min.

[0015] Optionally, the coating method includes one of spin coating, blade coating and slit coating;

[0016] The organic solvent includes at least one of N,N-dimethylformamide and dimethyl sulfoxide.

[0017] According to a third aspect of the present invention, a wide bandgap perovskite solar cell is provided, wherein the wide bandgap perovskite solar cell comprises a first electrode, a perovskite light absorbing layer and a second electrode stacked in sequence, and the perovskite light absorbing layer comprises the low-dimensional layered wide bandgap perovskite material as described above in the present invention and / or the low-dimensional layered wide bandgap perovskite material prepared by the preparation method as described above in the present invention.

[0018] Optionally, the wide bandgap perovskite solar cell further includes a hole transport layer disposed between the first electrode and the perovskite light absorbing layer, and an electron transport layer and a hole blocking layer disposed between the perovskite light absorbing layer and the second electrode; the electron transport layer is disposed close to the perovskite light absorbing layer, and the hole blocking layer is disposed close to the second electrode.

[0019] A fourth aspect of the present invention provides a method for preparing a wide bandgap perovskite solar cell, wherein the method for preparing a wide bandgap perovskite solar cell comprises the following steps:

[0020] providing a first electrode;

[0021] A perovskite light-absorbing layer is formed on the first electrode, wherein the perovskite light-absorbing layer comprises the low-dimensional layered wide-bandgap perovskite material of the present invention as described above and / or the low-dimensional layered wide-bandgap perovskite material prepared by the preparation method of the present invention as described above;

[0022] A second electrode is formed on the perovskite light-absorbing layer to obtain the wide-bandgap perovskite solar cell.

[0023] Optionally, the method for preparing the wide bandgap perovskite solar cell further comprises the following steps:

[0024] forming a hole transport layer between the first electrode and the perovskite light absorbing layer;

[0025] An electron transport layer and a hole blocking layer are formed between the perovskite light absorbing layer and the second electrode. The electron transport layer is arranged close to the perovskite light absorbing layer, and the hole blocking layer is arranged close to the second electrode.

[0026] Beneficial effect: The low-dimensional layered wide bandgap perovskite material provided by the present invention has excellent environmental stability, and the bandgap can reach 1.70 eV. The open circuit voltage of the perovskite solar cell based on the low-dimensional layered wide bandgap perovskite material can reach 1.27 V. 2 A photoelectric conversion efficiency of 20.18% can be obtained under the effective area, and it has good stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1This is the XRD diagram of the low-dimensional layered wide-bandgap perovskite light-absorbing layer in Example 1.

[0028] Figure 2 The GIWAXS test results of the low-dimensional layered wide-bandgap perovskite light-absorbing layer in Example 1, where (a) is the intensity-q z Curve graph, (b) is q z -q xy Graph.

[0029] Figure 3 This is a current density-voltage curve of the wide bandgap perovskite solar cell in Example 1.

[0030] Figure 4 This is a graph showing the external quantum efficiency test results of the wide bandgap perovskite solar cell in Example 1.

[0031] Figure 5 The wide bandgap perovskite solar cell stability test results in Example 1, wherein (a) is J sc - time curve diagram, (b) is the normalized PCE-time curve diagram. DETAILED DESCRIPTION

[0032] The present invention provides a low-dimensional layered wide bandgap perovskite material, a wide bandgap perovskite solar cell and a preparation method thereof. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0033] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0034] The embodiment of the present invention provides a low-dimensional layered wide band gap perovskite material (belonging to RP-type perovskite, which is a layered perovskite structure), wherein the chemical formula of the low-dimensional layered wide band gap perovskite material is A2B n-1 Pb n X 3n+1 , wherein A is at least one of 4-fluoro-phenethylammonium ion, phenethylammonium ion, butylammonium ion, and octylammonium ion, B is at least one of methylamine ion, formamidine ion, and cesium ion, X is at least one halogen ion, and n is a value greater than 1 and less than 10 (n is the number of restricted lead halide octahedra).

[0035] The low-dimensional layered wide bandgap perovskite material provided in the embodiment of the present invention has excellent environmental stability, and the bandgap can reach 1.70 eV. The open circuit voltage of the perovskite solar cell based on the low-dimensional layered wide bandgap perovskite material can reach 1.27 V. 2 A photoelectric conversion efficiency of 20.18% can be obtained under the effective area, and it has good stability.

[0036] In some embodiments, the value of n is greater than or equal to 5 and less than or equal to 7, for example, it can be 5, 5.5, 6, 6.5 or 7.

[0037] In some embodiments, the low-dimensional layered wide bandgap perovskite material is in powder form or thin film form.

[0038] In some embodiments, the chemical formula of the low-dimensional layered wide bandgap perovskite material is (4F-PEA)2(FA 0.73 Cs 0.27 ) 5.5 Pb 6.5 (I 0.78 Br 0.22 ) 20.5 , 4F-PEA is 4-fluoro-phenethylammonium ion, and FA is formamidinium ion.

[0039] The embodiment of the present invention further provides a method for preparing the low-dimensional layered wide bandgap perovskite material as described above, which comprises the following steps:

[0040] S11, press A2B n-1 Pb n X 3n+1 The stoichiometric ratio of each element in the precursor solution is determined by adding AI, BX and PbX into an organic solvent for mixing or adding ABr, BX and PbX into an organic solvent for mixing to obtain a precursor solution; wherein AI is at least one of 4-fluoro-phenethylammonium iodide (4F-PEAI), phenethylammonium iodide (PEAI), butylammonium iodide (BAI), and octylammonium iodide (OAI); ABr is at least one of 4-fluoro-phenethylammonium bromide (4F-PEABr), phenethylammonium bromide (PEABr), and octylammonium iodide (OAI). BX is at least one of methylamine halides (e.g., methylamine chloride, referred to as MACl; methylamine bromide, referred to as MABr; methylamine iodide, referred to as MAI, etc.), formamidine halides (e.g., formamidine chloride, referred to as FACl; formamidine bromide, referred to as FABr; formamidine iodide, referred to as FAI, etc.), and cesium halides (e.g., CsCl, CsBr, CsI, etc.), and PbX is at least one of lead halides (e.g., PbCl2, PbBr2, PbI2, etc.);

[0041] S12. After reacting the precursor solution, a powdered low-dimensional layered wide bandgap perovskite material is obtained; or, after coating the perovskite precursor solution and annealing, a thin film-shaped low-dimensional layered wide bandgap perovskite material (i.e., a low-dimensional layered wide bandgap perovskite film) is obtained.

[0042] The preparation method provided by the present invention is simple and can prepare a low-dimensional layered wide band gap perovskite material in powder form or a low-dimensional layered wide band gap perovskite material in film form.

[0043] In some embodiments, the annealing temperature is 105-120°C (for example, 105°C, 110°C, 115°C or 120°C, etc.), and the annealing time is 20-40 min (for example, 20 min, 25 min, 30 min, 35 min or 40 min, etc.).

[0044] In some embodiments, the coating method includes one of spin coating, blade coating and slit coating, but is not limited thereto.

[0045] In some embodiments, the organic solvent includes at least one of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), but is not limited thereto.

[0046] An embodiment of the present invention further provides a wide bandgap perovskite solar cell, wherein the wide bandgap perovskite solar cell comprises a first electrode, a perovskite light absorbing layer and a second electrode stacked in sequence, and the perovskite light absorbing layer comprises the low-dimensional layered wide bandgap perovskite material as described above in the embodiment of the present invention and / or the low-dimensional layered wide bandgap perovskite material prepared by the preparation method as described above in the embodiment of the present invention.

[0047] The structural type of the wide bandgap perovskite solar cell is not limited in the embodiments of the present invention, and it may be a trans structure (pin type) or a regular structure (nip type).

[0048] The first electrode includes a flexible substrate or a rigid substrate and an electrode material layer located on the surface of the flexible substrate or the rigid substrate, the flexible substrate includes one of a polystyrene (PET) substrate and a polyethylene naphthalate (PEN), the rigid substrate includes glass, and the electrode material layer includes a transparent conductive oxide, and the transparent conductive oxide includes fluorine-doped tin oxide (FTO), indium tin oxide (ITO), and aluminum-doped zinc oxide (AZO). For example, the first electrode is ITO conductive glass.

[0049] In some embodiments, the second electrode includes at least one of silver, copper, aluminum and gold, but is not limited thereto, and the thickness of the second electrode is 60 to 150 nm, for example, it can be 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm or 150 nm.

[0050] Of course, the first electrode can also be at least one of silver, copper, aluminum and gold, but is not limited thereto. In this case, the second electrode is a flexible substrate or a rigid substrate and an electrode material layer located on the surface of the flexible substrate or the rigid substrate. The selection of the electrode material layer is as described above.

[0051] In some embodiments, the thickness of the perovskite light absorbing layer is 300-600 nm, for example, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm or 600 nm.

[0052] In some embodiments, the wide bandgap perovskite solar cell further includes a hole transport layer disposed between the first electrode and the perovskite light absorbing layer, and an electron transport layer and a hole blocking layer disposed between the perovskite light absorbing layer and the second electrode; the electron transport layer is disposed close to the perovskite light absorbing layer, and the hole blocking layer is disposed close to the second electrode.

[0053] In some embodiments, the thickness of the hole transport layer is 5 to 25 nm, for example, 5 nm, 10 nm, 15 nm, 20 nm or 25 nm.

[0054] In some embodiments, the hole transport layer includes a hole transport material, and the hole transport material includes an organic polymer or a self-assembled monolayer (SAM) material, etc. The organic polymer includes but is not limited to at least one of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) and poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS); the self-assembled monolayer (SAM) material includes but is not limited to at least one of [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (2PACz), [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz) and [4-(7H-dibenzocarbazole-7-yl)butyl]phosphonic acid (4PADCB).

[0055] In some embodiments, the thickness of the electron transport layer is 20 to 50 nm, for example, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm or 50 nm.

[0056] In some embodiments, the electron transport layer includes an electron transport material, wherein the electron transport material includes at least one of an organic electron transport material and an inorganic electron transport material, wherein the organic electron transport material includes [6,6]-phenyl-C 61 - at least one of methyl butyrate (PC61BM) and C60, and the inorganic electron transport material includes at least one of titanium dioxide (TiO2) and tin dioxide (SnO2), but is not limited thereto.

[0057] In some embodiments, the hole blocking layer has a thickness of 4 to 8 nm, for example, 4 nm, 5 nm, 6 nm, 7 nm or 8 nm.

[0058] In some embodiments, the hole blocking layer includes a hole blocking material, and the hole blocking material includes at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP, also known as bathocuproine) and 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBI), but is not limited thereto.

[0059] The embodiment of the present invention further provides a method for preparing a wide bandgap perovskite solar cell (taking a pin type as an example), wherein the method for preparing a wide bandgap perovskite solar cell comprises the steps of:

[0060] S21, providing a first electrode;

[0061] S22, forming a hole transport layer on the first electrode;

[0062] S23, forming a perovskite light absorption layer on the hole transport layer; the perovskite light absorption layer comprises the low-dimensional layered wide band gap perovskite material as described above in the embodiment of the present invention and / or the low-dimensional layered wide band gap perovskite material prepared by the preparation method as described above in the embodiment of the present invention;

[0063] S24, forming an electron transport layer on the perovskite light absorbing layer;

[0064] S25, forming a hole blocking layer on the electron transport layer;

[0065] S26. Forming a second electrode on the hole blocking layer to obtain the wide bandgap perovskite solar cell.

[0066] In step S22 , the hole transport layer may be prepared by spin coating. Specifically, the hole transport material may be mixed with a solvent and then spin coated.

[0067] In step S24, the electron transport layer can be prepared by spin coating. Specifically, the electron transport material can be mixed with a solvent and then spin coated. The electron transport layer can also be prepared by thermal evaporation deposition, for example, C60 was deposited by thermal evaporation at an evaporation rate of to form an electron transport layer.

[0068] In step S25 , a thermal evaporation deposition method may be used to form the hole blocking layer.

[0069] In step S26 , the second electrode may be formed by thermal evaporation deposition.

[0070] The present invention will be further described below by means of specific examples.

[0071] Example 1

[0072] This embodiment provides a method for preparing a wide bandgap perovskite solar cell, comprising the following steps:

[0073] (1) Treatment of ITO conductive glass

[0074] The ITO conductive glass was ultrasonically cleaned in a diluted detergent, deionized water and isopropanol in turn for 20 minutes each. After drying, the cleaned ITO conductive glass was treated with ultraviolet ozone for 30 minutes to obtain a clean ITO conductive glass.

[0075] (2) Preparation of hole transport layer on ITO conductive glass

[0076] A 4PADCB solution (the 4PADCB solution was dissolved in ethanol and the concentration was 1.0 mg / mL) was spin-coated on the ITO conductive glass at a rotation speed of 3000 rpm for 30 seconds, and then annealed at 100° C. for 10 minutes to obtain a hole transport layer with a thickness of 5 nm.

[0077] (3) Preparation of low-dimensional layered wide-bandgap perovskite light-absorbing layer on the hole transport layer

[0078] 64.1 mg of 4F-PEAI, 82.6 mg of FAI, 276.6 mg of PbI2, 66.0 mg of PbBr2, 38.4 mg of CsBr, and 4.6 mg of MACl (as an additive) were added to a mixed solution of 570 μL of DMF and 30 μL of DMSO and shaken for 8 hours to obtain a precursor solution;

[0079] 45 μL of the precursor solution was added to the hole transport layer and spin-coated at 5000 rpm for 60 seconds. During the spin-coating process, 0.3 MPa of nitrogen was blown through the perovskite wet film to accelerate the evaporation of the solvent. Then it was placed on a heating table and annealed at 110°C for 30 minutes to obtain a low-dimensional layered wide-bandgap perovskite light-absorbing layer with a thickness of 430 nm. The chemical formula of the low-dimensional layered wide-bandgap perovskite is (4F-PEA)2(FA 0.73 Cs 0.27 ) 5.5 Pb 6.5 (I 0.78 Br 0.22 ) 20.5 , the band gap is 1.70eV.

[0080] (4) Preparation of electron transport layer, hole blocking layer and silver electrode on the low-dimensional layered wide-bandgap perovskite light-absorbing layer

[0081] A PC61BM solution (PC61BM dissolved in chlorobenzene, PC61BM concentration of 10 mg / mL) was spin-coated on the low-dimensional layered wide-bandgap perovskite light-absorbing layer at a rotation speed of 3000 rpm for 30 s to obtain a PC61BM layer with a thickness of 35 nm;

[0082] exist At an evaporation rate of , a C60 layer with a thickness of 10 nm is deposited on the PC61BM layer by a thermal evaporation deposition method to obtain an electron transport layer (including a stacked PC61BM layer and a C60 layer);

[0083] exist At an evaporation rate of , a BCP with a thickness of 5 nm was deposited on the C60 layer by thermal evaporation deposition to obtain a hole blocking layer;

[0084] exist A silver electrode with a thickness of 90 nm was deposited on the hole blocking layer by thermal evaporation deposition at an evaporation rate of .

[0085] test:

[0086] (1) The low-dimensional layered wide bandgap perovskite light absorbing layer in Example 1 was subjected to an X-ray diffraction (XRD) test. The results are as follows: Figure 1 As shown, a peak of n=2 can be seen, confirming that it is a low-dimensional layered perovskite material.

[0087] (2) The low-dimensional layered wide-bandgap perovskite light-absorbing layer in Example 1 was subjected to grazing incidence wide-angle x-ray scattering (GIWAXS) test. The results are as follows: Figure 2 As shown (where q z represents the out-of-plane vector, q xy represents the in-plane vector), it can be seen that the low-dimensional layered wide-bandgap perovskite has a good orientation.

[0088] (3) The wide bandgap perovskite solar cell in Example 1 was subjected to transient scanning, and its current density-voltage curve was as follows: Figure 3 As shown in Figure 2, its photoelectric conversion efficiency (PCE) is 20.18%, the fill factor (FF) is 78.88%, and the short-circuit current (J sc ) is 20.16 mA·cm -2 , open circuit voltage (V oc ) is 1.27V.

[0089] (4) The external quantum efficiency of the wide bandgap perovskite solar cell in Example 1 was tested. The results are as follows Figure 4 As shown, it can be seen that its band gap Eg=1.70 eV (a wide band gap perovskite material), and the EQE reaches about 90%.

[0090] (5) The wide bandgap perovskite solar cell in Example 1 was tested for stability. The results are as follows Figure 5 As shown, it can be seen that the steady-state output efficiency of the wide bandgap perovskite solar cell in Example 1 is 19.9%, and after running for 500 hours, the PCE basically does not change, and has good stability.

[0091] In summary, the present invention provides a low-dimensional layered wide bandgap perovskite material, a wide bandgap perovskite solar cell and a preparation method thereof. The low-dimensional layered wide bandgap perovskite material provided by the present invention has excellent environmental stability, and the bandgap can reach 1.70 eV. The open circuit voltage of the perovskite solar cell based on the low-dimensional layered wide bandgap perovskite material can reach 1.27 V, and the bandgap can reach 1.27 V at 0.1 cm 2 A photoelectric conversion efficiency of 20.18% can be obtained under the effective area, and it has good stability.

[0092] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A low-dimensional layered wide bandgap perovskite material, characterized in that: The chemical formula of the low-dimensional layered wide bandgap perovskite material is A2B n-1 Pb n X 3n+1 , wherein A is at least one of 4-fluoro-phenethylammonium ion, phenethylammonium ion, butylammonium ion, and octylammonium ion, B is at least one of methylamine ion, formamidine ion, and cesium ion, X is at least one halogen ion, and the value of n is greater than 1 and less than 10.

2. The low-dimensional layered wide bandgap perovskite material according to claim 1, characterized in that: The low-dimensional layered wide bandgap perovskite material is in powder form or film form.

3. The low-dimensional layered wide bandgap perovskite material according to claim 1, characterized in that: The chemical formula of the low-dimensional layered wide bandgap perovskite material is (4F-PEA)2(FA 0.73 Cs 0.27 ) 5.5 Pb 6.5 (I 0.78 Br 0.22 ) 20.5 , 4F-PEA is 4-fluoro-phenethylammonium ion, and FA is formamidinium ion.

4. A method for preparing the low-dimensional layered wide bandgap perovskite material according to claim 1, characterized in that: The steps include: Press A2B n-1 Pb n X 3n+1 The stoichiometric ratio of each element in the mixture is adjusted, and AI, BX and PbX are added to an organic solvent for mixing or ABr, BX and PbX are added to an organic solvent for mixing to obtain a precursor solution; wherein AI is at least one of 4-fluoro-phenethylammonium iodide, phenethylammonium iodide, butylammonium iodide, and octylammonium iodide; ABr is at least one of 4-fluoro-phenethylammonium bromide and phenethylammonium bromide; BX is at least one of methylamine halide, formamidine halide, and cesium halide; and PbX is at least one lead halide; After the precursor solution is reacted, a low-dimensional layered wide band gap perovskite material in powder form is obtained; or, after the perovskite precursor solution is coated and annealed, a low-dimensional layered wide band gap perovskite material in film form is obtained.

5. The preparation method according to claim 4, characterized in that: The annealing temperature is 105-120° C., and the annealing time is 20-40 minutes.

6. The preparation method according to claim 4, characterized in that: The coating method includes one of spin coating, blade coating and slit coating; The organic solvent includes at least one of N,N-dimethylformamide and dimethyl sulfoxide.

7. A wide bandgap perovskite solar cell, characterized in that: The wide bandgap perovskite solar cell comprises a first electrode, a perovskite light-absorbing layer and a second electrode which are stacked in sequence, and the perovskite light-absorbing layer comprises the low-dimensional layered wide bandgap perovskite material according to any one of claims 1 to 3 and / or the low-dimensional layered wide bandgap perovskite material prepared by the preparation method according to any one of claims 4 to 6.

8. The wide bandgap perovskite solar cell according to claim 7, characterized in that: The wide bandgap perovskite solar cell also includes a hole transport layer arranged between the first electrode and the perovskite light absorbing layer, and an electron transport layer and a hole blocking layer arranged between the perovskite light absorbing layer and the second electrode; the electron transport layer is arranged close to the perovskite light absorbing layer, and the hole blocking layer is arranged close to the second electrode.

9. A method for preparing a wide bandgap perovskite solar cell, characterized in that: The method for preparing the wide bandgap perovskite solar cell comprises the following steps: providing a first electrode; A perovskite light-absorbing layer is formed on the first electrode, wherein the perovskite light-absorbing layer comprises the low-dimensional layered wide-bandgap perovskite material according to any one of claims 1 to 3 and / or the low-dimensional layered wide-bandgap perovskite material prepared by the preparation method according to any one of claims 4 to 6; A second electrode is formed on the perovskite light-absorbing layer to obtain the wide-bandgap perovskite solar cell.

10. The preparation method according to claim 9, characterized in that: The method for preparing the wide bandgap perovskite solar cell further comprises the following steps: forming a hole transport layer between the first electrode and the perovskite light absorbing layer; An electron transport layer and a hole blocking layer are formed between the perovskite light absorbing layer and the second electrode. The electron transport layer is arranged close to the perovskite light absorbing layer, and the hole blocking layer is arranged close to the second electrode.

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