A kind of double mesostructure all-inorganic perovskite solar cell and its preparation method

Abstract

The application belongs to the technical field of solar cells, and discloses a kind of double mesostructure all-inorganic perovskite solar cell and its preparation method, first synthesizes N type SnO2 mesoporous microsphere and P type NiO mesoporous microsphere, and ZrO2 cubic nanoframe particle;N type SnO2 mesoporous microsphere dispersion, ZrO2 cubic nanoframe particle dispersion, P type NiO mesoporous microsphere dispersion are coated in turn on the conductive glass containing TiO2 dense layer;After sintering, the cell skeleton composed of high-quality mesostructure electron transport layer, submicron pore structure insulating frame layer and mesostructure hole transport layer is obtained;CsPbI 3‑x Br x All-inorganic perovskite light absorption layer, and a carbon electrode is coated on the mesostructure hole transport layer to obtain a double mesostructure all-inorganic perovskite solar cell with inorganic materials in each functional layer, which is high-efficiency and stable.

Description

Technical Field

[0001] This invention relates to the field of solar cell technology, and in particular to a dual-mesoscopic structure all-inorganic perovskite solar cell and its fabrication method. Background Technology

[0002] Perovskite solar cells use perovskite material as the light-absorbing layer to generate electron-hole pairs. After separation, the electrons and holes are transported to the external circuit by the electron transport layer and hole transport layer, respectively, to complete the photoelectric conversion. They have the advantages of simple fabrication process, low production cost, and high photoelectric conversion efficiency, showing great development potential.

[0003] However, traditional organic-inorganic hybrid perovskite materials, containing organic components such as methylamine and formamidinium, are prone to decomposition and phase transitions under heat, humidity, light, and oxygen environments, resulting in poor long-term stability and severely restricting their industrial application. Using Cs... + Replacement of organic components to form CsPbI 3-x Br x All-inorganic perovskite materials can significantly improve thermal stability, environmental stability, and aging resistance, while also possessing a suitable band gap, high carrier mobility, and low defect state density, making them ideal materials for overcoming stability bottlenecks. If the instabilities present in the electron transport layer, hole transport layer, electrodes, and contact interfaces can be further resolved, industrial applications could be accelerated.

[0004] Therefore, it is necessary to develop a high-quality, large-grained CsPbI material where all functional layers are inorganic. 3-x Br x All-inorganic perovskite solar cells with light-absorbing layers and good contact interfaces are of great significance for the large-scale application and development of perovskite solar cells.

[0005] In view of this, the inventor of this case conducted in-depth research, which led to the creation of this case. Summary of the Invention

[0006] The purpose of this invention is to provide a method for forming high-quality, large-grained CsPbI. 3-x Br x A dual-mesoscopic structure of all-inorganic perovskite solar cells, featuring a light-absorbing layer and a good contact interface, can improve the high photoelectric conversion efficiency and long-term stability of solar cells.

[0007] Another objective of this invention is to provide a method for preparing a fully inorganic perovskite solar cell with a dual mesoscopic structure.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows: A dual-mesoscopic structure of an all-inorganic perovskite solar cell includes a conductive glass conductive layer, a cell frame, and a carbon electrode screen-printed on the cell frame. The battery skeleton is filled with CsPbI. 3-x Br x All-inorganic perovskite light-absorbing layer; The battery framework comprises a TiO2 dense layer, a mesoscopic electron transport layer, a submicron porous insulating framework layer, and a mesoscopic hole transport layer sequentially stacked on a conductive glass conductive layer. The battery framework has mesopores and submicron pores. The CsPbI... 3-x Br x The all-inorganic perovskite light-absorbing layer penetrates and spreads within the mesopores and submicron pores, and the carbon electrode is coated on the mesoscopic hole transport layer. The mesoscopic electron transport layer is prepared by self-assembly of 5-10 nm SnO2 nanocrystals to form 50-150 nm N-type mesoporous microspheres. The submicron porous insulating framework layer is prepared by 150-250 nm ZrO2 cubic nanoframework particles. The mesoscopic hole transport layer is prepared by self-assembly of 5-10 nm NiO nanocrystals to form 50-150 nm P-type mesoporous microspheres.

[0009] A method for fabricating a dual-mesoscopic structure all-inorganic perovskite solar cell includes the following steps: Step 1: Disperse SnO2 nanocrystals with an oleylamine ligand and a particle size of 5-10 nm in toluene to prepare a SnO2 nanocrystal dispersion with a concentration of 10-50 mg / mL. Prepare a deionized water: SnO2 nanocrystal particle toluene dispersion with a volume ratio of 15~20:1. Under the combined action of stirring and ultrasound, add the SnO2 nanocrystal particle toluene dispersion dropwise to the deionized water. After emulsification for 15~30 minutes, a transparent or semi-transparent ultra-micro emulsion is obtained. Add 2 to 4 times the volume of the ethanol / acetone mixture to the ultra-microemulsion to break the emulsion (the volume ratio of ethanol to acetone is 1:1 to 1:4), centrifuge at 6000 to 10000 rpm for 15 to 30 minutes, and collect the centrifuged material. Add 5-10 times the volume of the centrifuged material to a NOBF4 acetonitrile solution with a concentration of 5-10 mg / mL. Stir at 2000-3000 rpm for 30-60 minutes to remove the oleylamine ligand. Then centrifuge at 6000-10000 rpm for 15-30 minutes. Collect the centrifuged material to obtain 50-150 nm N-type SnO2 mesoporous microspheres. Step 2: Prepare a 2.5-5 mg / mL zirconium dichlorocerocene acetone solution. Add a 25 wt% ammonia solution to the zirconium dichlorocerocerocene acetone solution, controlling the volume ratio of ammonia solution to zirconium dichlorocerocerocene acetone solution to be 1 / 60-1 / 15. Transfer the obtained suspension to a high-pressure reactor with a polytetrafluoroethylene liner. Heat-treat at 180-200℃ for 6-12 hours, cool naturally to room temperature, and centrifuge at 6000-10000 rpm for 15-30 minutes. Collect the centrifuged material to obtain 150-250 nm ZrO2 cubic nanoframework particles. Step 3: Disperse NiO nanocrystals with a particle size of 5-10 nm and containing oleylamine ligands in toluene to prepare a NiO nanocrystal dispersion with a concentration of 10-50 mg / mL. Prepare a deionized water: NiO nanocrystal particle toluene dispersion with a volume ratio of 15~20:1. Under the combined action of stirring and ultrasound, add the NiO nanocrystal particle toluene dispersion dropwise to the deionized water. After emulsification for 15~30 minutes, a transparent or semi-transparent ultra-micro emulsion is obtained. Add 2 to 4 times the volume of the ethanol / acetone mixture to the ultra-microemulsion to break the emulsion. The volume ratio of ethanol to acetone is 1:1 to 1:4. Centrifuge at 6000 to 10000 rpm for 15 to 30 minutes and collect the centrifuged material. Add 5-10 times the volume of the centrifuged material to a NOBF4 acetonitrile solution with a concentration of 5-10 mg / mL. Stir at 2000-3000 rpm for 30-60 minutes to remove the oleylamine ligand. Then centrifuge at 6000-10000 rpm for 15-30 minutes. Collect the centrifuged material to obtain 50-150 nm P-type NiO mesoporous microspheres. Step 4: Disperse TiO2 nanocrystals with a particle size of 3-5 nm and containing oleic acid ligands in n-hexane to prepare a TiO2 nanocrystal dispersion with a concentration of 0.1-0.5 wt%. The conductive glass was placed on a heating plate at 50~100℃, and then the TiO2 nanocrystalline particles n-hexane dispersion was sprayed onto the conductive layer of the conductive glass. The air spraying parameters were: the distance between the nozzle and the conductive layer was 12~15 cm, the dispersion flow rate was 0.02~0.05 mL / min, the scanning speed was 8~15 mm / s, and the number of scans was 4~8. Afterwards, continue heating for 15-30 minutes to dry, and obtain a TiO2 nanocrystalline particle layer; Step 5: Disperse the N-type SnO2 mesoporous microspheres with a particle size of 50~150 nm prepared in step 1 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 4:1~5:2) to prepare an N-type SnO2 mesoporous microsphere dispersion with a concentration of 1.0~3.0wt%. The dispersion was sprayed onto the TiO2 nanocrystalline particle layer prepared in step 4, which was placed on a heating plate at 50~100℃. The air spraying parameters were: the distance between the nozzle and the TiO2 nanocrystalline particle layer was 10~15 cm, the dispersion flow rate was 0.05~0.15 mL / min, the scanning speed was 3~6 mm / s, and the number of scans was 2~4. Afterwards, continue heating for 15-30 minutes to dry, and obtain N-type SnO2 mesoporous microspheres; Step 6: Disperse the ZrO2 cubic nanoframework particles with a particle size of 150~250 nm prepared in step 2 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 4:1~5:2) to prepare a ZrO2 cubic nanoframework particle dispersion with a concentration of 1.5~3.0 wt%. The dispersion was sprayed onto the N-type SnO2 mesoporous microsphere layer prepared in step 5, which was placed on a heating plate at 50~100℃. The air spraying parameters were: the distance between the nozzle and the N-type SnO2 mesoporous microsphere layer was 10~15 cm, the dispersion flow rate was 0.1~0.2 mL / min, the scanning speed was 2~8 mm / s, and the number of scans was 3~6. Afterwards, continue heating for 15-30 minutes to dry, and obtain a ZrO2 cubic nanoframework particle layer; Step 7: Disperse the P-type NiO mesoporous microspheres with a particle size of 50~150 nm prepared in step 3 in anhydrous ethanol / ethylene glycol monomethyl ether with a volume ratio of 4:1~5:2 to prepare a P-type NiO mesoporous microsphere dispersion with a concentration of 1.0~3.0wt%. The dispersion was sprayed onto the ZrO2 cubic nanoframework particle layer prepared in step 6, which was placed on a heating plate at 50~100℃. The air spraying parameters were: the distance between the nozzle and the ZrO2 cubic nanoframework particle layer was 10~15 cm, the dispersion flow rate was 0.05~0.15 mL / min, the scanning speed was 3~6 mm / s, and the number of scans was 2~4. The sample was then sintered in an air atmosphere at 400-500 °C for 30-60 minutes to obtain a battery framework. The battery framework includes a TiO2 dense layer (15-25 nm), a mesoscopic electron transport layer (150-300 nm), a submicron porous insulating framework layer (0.5-1 μm), and a mesoscopic hole transport layer (150-300 nm) sequentially stacked on a conductive glass conductive layer. Step 8: Fill the mesopores and submicron pores within the battery framework prepared in Step 7 with CsPbI using spin coating at a speed of 8000~12000 rpm. 3-x Br x The perovskite light-absorbing layer precursor solution is soaked in chlorobenzene or ethyl acetate for 5-10 minutes; Carbon electrodes are then screen-printed onto the hole transport layer of the mesoscopic structure, and the cells are heat-treated at 100~250 ℃ for 10~30 minutes to obtain a fully inorganic perovskite solar cell with a dual mesoscopic structure.

[0010] Furthermore, in the battery skeleton, the thickness of the TiO2 dense layer is 15~25 nm, the thickness of the mesoscopic electron transport layer is 150~300 nm, the thickness of the submicron porous insulating framework layer is 0.5~1 μm, and the thickness of the mesoscopic hole transport layer is 150~300 nm.

[0011] After adopting the above technical solution, the all-inorganic perovskite solar cell with a dual mesoscopic structure of the present invention has the following beneficial effects: the insulating framework layer in the cell skeleton has a submicron porous structure, which can fully fill and generate high-quality large-grain CsPbI 3-x Br x The light-absorbing layer is entirely inorganic perovskite; the electron transport layer and hole transport layer have a mesoscopic structure, which can fully penetrate CsPbI. 3-x Br x A good contact interface can ensure the high photoelectric conversion efficiency of solar cells.

[0012] This invention discloses a method for fabricating a dual-mesoscopic structure all-inorganic perovskite solar cell. Each functional layer, including an electron transport layer, a light absorption layer, a hole transport layer, and a carbon electrode, is composed of inorganic materials. The mesoscopic electron transport layer is prepared by self-assembly of 5-10 nm SnO2 nanocrystals to form 50-150 nm N-type mesoporous microspheres; the submicron porous insulating framework layer is prepared by 150-250 nm ZrO2 cubic nanoframework particles; and the mesoscopic hole transport layer is prepared by self-assembly of 5-10 nm NiO nanocrystals to form 50-150 nm P-type mesoporous microspheres. This method can ensure the long-term stability of the solar cell to a certain extent. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the battery structure of the present invention. In the figure: FTO is a conductive glass with a fluorine-doped SnO2 conductive layer; ETL stands for Electron Transport Layer; PVK is perovskite; Carbon electrode is a carbon electrode; P-type Mesoporous microspheres are P-type mesoporous microspheres. N-type Mesoporous microspheres are N-type mesoporous microspheres; Light refers to light (the direction of illumination); Nanoframe layer is a nanoframework layer; ZrO2Nanoframe refers to ZrO2 nanoframework particles; SnO2microsphere is a mesoporous microsphere made of SnO2.

[0014] The figure also shows transmission electron microscopy (TEM) images of ZrO2 nanoframe particles and SnO2N-type mesoporous microspheres. Detailed Implementation

[0015] Example 1 I. Preparation This invention discloses a method for fabricating a dual-mesoscopic structure all-inorganic perovskite solar cell, comprising the following steps: Step 1: Disperse SnO2 nanocrystals with an oleylamine ligand and a particle size of 5 nm in toluene to prepare a SnO2 nanocrystal dispersion with a concentration of 10 mg / mL. Prepare a deionized water: SnO2 nanocrystal particle toluene dispersion with a volume ratio of 15:1. Under the combined action of stirring (3000 rpm) and ultrasound (180W), slowly add the SnO2 nanocrystal particle toluene dispersion to the deionized water. After emulsification for 30 minutes, a semi-transparent ultra-micro emulsion is obtained. Add 4 times the volume of the ultraemulsion to an ethanol / acetone (volume ratio 1:4) mixture to break the emulsion, centrifuge at 10,000 rpm for 30 minutes, and collect the centrifuged material; add 10 times the volume of the centrifuged material to a tetrafluoroborate nitrite (NOBF4) acetonitrile solution (concentration 5 mg / mL), stir at 3,000 rpm for 60 minutes to remove the oleylamine ligand, and then centrifuge at 10,000 rpm for 30 minutes, collect the centrifuged material, and obtain 100 nm N-type SnO2 mesoporous microspheres.

[0016] Step 2: Prepare a 5 mg / mL zirconium dichlorocerocene acetone solution. Add a 25 wt% ammonia solution to the zirconium dichlorocerocerocene acetone solution, controlling the volume ratio of ammonia solution to zirconium dichlorocerocerocene acetone solution to 1:15. Transfer the obtained suspension to a high-pressure reactor with a polytetrafluoroethylene liner, heat-treat at 200℃ for 12 hours, cool naturally to room temperature, centrifuge at 6000 rpm for 15 minutes, collect the centrifuged material, and obtain 250 nm ZrO2 cubic nanoframework particles.

[0017] Step 3: Disperse NiO nanocrystals with a particle size of 5 nm and containing oleylamine ligands in toluene to prepare a NiO nanocrystal dispersion with a concentration of 10 mg / mL. A deionized water to NiO nanocrystal particle toluene dispersion with a volume ratio of 15:1 was prepared. Under the combined action of stirring (3000 rpm) and ultrasound (180 W), the NiO nanocrystal particle toluene dispersion was slowly added dropwise to the deionized water. After emulsification for 30 minutes, a semi-transparent ultra-micro emulsion was obtained. Add 4 times the volume of the ultraemulsion to an ethanol / acetone (volume ratio 1:4) mixture to break the emulsion, centrifuge at 10,000 rpm for 30 minutes, and collect the centrifuge. Add 10 times the volume of the centrifuge to an acetonitrile solution (concentration 5 mg / mL), stir at 3,000 rpm for 60 minutes to remove the oleylamine ligand, and centrifuge again at 10,000 rpm for 30 minutes. Collect the centrifuge to obtain 100 nm P-type NiO mesoporous microspheres.

[0018] Step 4: Disperse TiO2 nanocrystals with an oleic acid ligand and a particle size of 3.6 nm in n-hexane to prepare a TiO2 nanocrystal dispersion with a concentration of 0.1 wt%. The conductive glass was placed on a 50°C heating plate, and then a hexane dispersion of TiO2 nanocrystal particles was sprayed onto the conductive layer of the conductive glass. The air spraying parameters were: 12 cm distance between the nozzle and the conductive layer, 0.02 mL / min flow rate of the dispersion, 10 mm / s scanning speed, and 4 scans. After that, the glass was heated for 30 minutes to dry, and a TiO2 nanocrystal particle layer was obtained. Step 5: Disperse the 100 nm N-type SnO2 mesoporous microspheres prepared in Step 1 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 5:2) to prepare an N-type SnO2 mesoporous microsphere dispersion with a concentration of 1.0 wt%. The dispersion was sprayed onto the TiO2 nanocrystalline particle layer prepared in step 4 and placed on a heating plate at 100℃. The air spraying parameters were: the distance between the nozzle and the TiO2 nanocrystalline particle layer was 15 cm, the dispersion flow rate was 0.05 mL / min, the scanning speed was 4 mm / s, and the number of scans was 2. Afterwards, continue heating for 30 minutes to dry, and obtain N-type SnO2 mesoporous microspheres; Step 6: Disperse the 250 nm ZrO2 cubic nanoframework particles prepared in step 2 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 5:2) to prepare a ZrO2 cubic nanoframework particle dispersion with a concentration of 2.0 wt%. The dispersion was sprayed onto the N-type SnO2 mesoporous microsphere layer prepared in step 5, which was placed on a heating plate at 100℃. The air spraying parameters were: the distance between the nozzle and the N-type SnO2 mesoporous microsphere layer was 15 cm, the dispersion flow rate was 0.15 mL / min, the scanning speed was 5 mm / s, and the number of scans was 4. After that, the mixture was heated for 30 minutes to dry, and a ZrO2 cubic nanoframework particle layer was obtained. Step 7: Disperse the 100 nm P-type NiO mesoporous microspheres prepared in step 3 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 5:2) to prepare a 1.0 wt% P-type NiO mesoporous microsphere dispersion. The dispersion was sprayed onto the ZrO2 cubic nanoframework particle layer prepared in step 6 and placed on a heating plate at 100°C. The air spraying parameters were: the distance between the nozzle and the ZrO2 cubic nanoframework particle layer was 15 cm, the dispersion flow rate was 0.05 mL / min, the scanning speed was 4 mm / s, and the number of scans was 2. Subsequently, the sample was sintered at 450 °C in an air atmosphere for 30 minutes to obtain a battery skeleton consisting of a TiO2 dense layer (20 nm, prepared from TiO2 nanocrystals), a mesoscopic electron transport layer (300 nm), a submicron porous insulating framework layer (0.7 μm), and a mesoscopic hole transport layer (300 nm) sequentially stacked on a conductive glass conductive layer.

[0019] Step 8: Using a spin-coating method at a speed of 10,000 rpm, fill the mesopores and submicron pores within the battery framework prepared in Step 7 with a CsPbI2Br perovskite light absorption layer precursor solution (solute molar ratio: CsI:PbI2:PbBr2 = 2:1:1, solvent: dimethyl sulfoxide, total cations: CsI2, PbI2, PbBr2 = 2:1 ... + +Pb 2+ A carbon electrode (20 μm) was prepared by screen printing commercially available carbon paste onto the hole transport layer of the mesoscopic structure after soaking in chlorobenzene for 5 minutes at a concentration of 1.0 mol / L. Subsequently, the electrode was subjected to heat treatment at 100 °C for 10 minutes and 250 °C for 5 minutes to obtain a double mesoscopic structure CsPbI2Br all-inorganic perovskite solar cell.

[0020] This invention discloses a dual-mesoscopic structure all-inorganic perovskite solar cell, such as... Figure 1 As shown, the battery includes conductive glass (FTO is a conductive glass with a fluorine-doped SnO2 conductive layer), and a dense layer made of TiO2 nanocrystals stacked sequentially on the conductive glass, a mesoscopic electron transport layer made of SnO2 nanocrystals self-assembled N-type mesoporous microspheres, a submicron porous insulating framework layer made of ZrO2 cubic nanoframeworks, a mesoscopic hole transport layer made of NiO nanocrystals self-assembled P-type mesoporous microspheres, and CsPbI filled within the battery skeleton. 3-xBr x An all-inorganic perovskite light-absorbing layer. A carbon electrode was coated onto the mesoscopic hole transport layer to obtain an all-inorganic perovskite solar cell with a dual mesoscopic structure where all functional layers are inorganic materials. The figure also shows the transmission electron microscopy morphology of self-assembled N-type mesoporous microspheres from ZrO2 cubic nanoframework particles and SnO2 nanocrystal particles.

[0021] II. Performance Testing This invention discloses a dual-mesoscopic structure all-inorganic perovskite solar cell. Compared with traditional mesoscopic structure all-inorganic perovskite solar cells, the submicron porous insulating framework layer significantly increases the grain size of the light-absorbing layer. Furthermore, the insertion of a mesoscopic hole transport layer between the traditional all-inorganic perovskite / carbon electrodes creates excellent interfacial contact, significantly reduces interfacial defects, and substantially improves hole extraction capability. A 1 cm⁻¹ solar cell was fabricated. 2 The photoelectric conversion efficiency of the dual-mesoscopic structure CsPbI2Br all-inorganic perovskite solar cell reached 13.5%~14.5%.

[0022] Test method: Current density-voltage ratio of CsPbI2Br all-inorganic perovskite solar cells with dual mesoscopic structure. J-V The characteristic curve test was conducted using a solar simulator (SS-F5-3A, manufactured by Kuang Yen Technology, Taiwan) equipped with a Keithley 2400 digital source meter. The light source was set to the standard AM 1.5G solar spectrum with a light intensity of 100 mW·cm². -2 Before each test, the simulator's light intensity is precisely calibrated using a certified standard silicon reference cell, and the irradiance is confirmed using a calibration spectrometer. J-V The curve's scan range is set to 0.2 V to 1.2 V, using forward scan ( (0.2 V → 1.2 V). The voltage step size for the test was set to 20 mV, and the delay time was 10 ms.

[0023] Long-term stability data are obtained by testing the photoelectric conversion efficiency of the device after it has been exposed to standard simulated sunlight for 1000 hours, and then comparing it with the initial efficiency to calculate the percentage.

[0024] Test data: The following shows 5 sets of data that passed. J-V The open-circuit voltage obtained by the test ( V oc ), short-circuit current ( J sc ), fill factor ( FF The photoelectric conversion efficiency (PCE) data are shown in Table 1 below. Furthermore, the efficiency of this group of devices remained at 98% of its initial value after 1000 hours of continuous exposure to standard simulated sunlight.

[0025] Table 1. Device in Example 1 passes... J-V The four photoelectric performance parameters obtained from the test

[0026] As shown in Table 1 above, in the five sets of photoelectric performance data for the device in Example 1, the open-circuit voltage is >1.20 V and the short-circuit current is >14.50 mA·cm. -2 The fill factor is >76%, and the photoelectric conversion efficiency ranges from a minimum of 13.77% to a maximum of 14.48%, fluctuating between 13.5% and 14.5% with minimal overall variation and good repeatability. This high photoelectric conversion efficiency is primarily attributed to the battery framework, which contains a complete functional layer and undergoes high-temperature sintering, significantly reducing recombination losses caused by relying solely on carbon electrodes for hole extraction. Long-term stability data indicates that the efficiency showed virtually no degradation under the test conditions. This is due to the excellent stability of the CsPbI2Br all-inorganic perovskite, the efficient extraction of electrons and holes to the external circuit, low recombination rates, and the protective effect of the tens-of-micrometers-thick carbon electrode.

[0027] Example 2 This invention discloses a method for fabricating a dual-mesoscopic structure all-inorganic perovskite solar cell, comprising the following steps: Step 1: Disperse SnO2 nanocrystals with an oleylamine ligand and a particle size of 7 nm in toluene to prepare a SnO2 nanocrystal dispersion with a concentration of 15 mg / mL. Prepare a deionized water: SnO2 nanocrystal particle toluene dispersion with a volume ratio of 20:1. Under the combined action of stirring (3000 rpm) and ultrasound (180W), slowly add the SnO2 nanocrystal particle toluene dispersion to the deionized water. After emulsification for 30 minutes, a semi-transparent ultra-micro emulsion is obtained. Add 8 times the volume of the ultra-microemulsion to the ethanol / acetone (volume ratio 1:1) mixture to break the emulsion, centrifuge at 8000 rpm for 30 minutes, and collect the centrifuged material. Add 6 times the volume of the centrifuged material to NOBF4 acetonitrile solution (concentration of 8 mg / mL), stir at 3000 rpm for 60 minutes to remove oleylamine ligands, then centrifuge at 8000 rpm for 30 minutes, collect the centrifuged material, and obtain 150 nm N-type SnO2 mesoporous microspheres.

[0028] Step 2: Prepare a 5 mg / mL zirconium dichlorophenoxyacetone solution. Add a 25 wt% ammonia solution dropwise to the zirconium dichlorophenoxyacetone solution, controlling the volume ratio of ammonia solution to zirconium dichlorophenoxyacetone solution to 1:15. Transfer the obtained suspension to a high-pressure reactor with a polytetrafluoroethylene liner, heat-treat at 200℃ for 12 hours, allow to cool naturally to room temperature, centrifuge at 6000 rpm for 15 minutes, collect the centrifuged material, and obtain 250 nm ZrO2 cubic nanoframework particles. Step 3: Disperse 7 nm NiO nanocrystals containing oleylamine ligands in toluene to prepare a 15 mg / mL NiO nanocrystal dispersion. A deionized water to NiO nanocrystal particle toluene dispersion with a volume ratio of 20:1 was prepared. Under the combined action of stirring (3000 rpm) and ultrasound (180 W), the NiO nanocrystal particle toluene dispersion was slowly added dropwise to the deionized water. After emulsification for 30 minutes, a semi-transparent ultra-micro emulsion was obtained. Add 8 times the volume of the ultra-microemulsion to the ethanol / acetone (volume ratio 1:1) mixture to break the emulsion, centrifuge at 8000 rpm for 30 minutes, and collect the centrifuged material. Add 6 times the volume of the centrifuged material to NOBF4 acetonitrile solution (concentration of 8 mg / mL), stir at 3000 rpm for 60 minutes to remove oleylamine ligands, then centrifuge at 8000 rpm for 30 minutes, collect the centrifuged material, and obtain 150 nm P-type NiO mesoporous microspheres.

[0029] Step 4: Disperse TiO2 nanocrystals with oleic acid ligands with a particle size of 3.6 nm in n-hexane to prepare a TiO2 nanocrystal dispersion with a concentration of 0.1 wt%. The conductive glass was placed on a 50°C heating plate, and then the TiO2 nanocrystalline particles n-hexane dispersion was sprayed onto the conductive layer of the conductive glass. The air spraying parameters were: the distance between the nozzle and the conductive layer was 12 cm, the dispersion flow rate was 0.02 mL / min, the scanning speed was 10 mm / s, and the number of scans was 4. Afterwards, continue heating for 30 minutes to dry, and obtain a TiO2 nanocrystalline particle layer; Step 5: Disperse the 150 nm N-type SnO2 mesoporous microspheres prepared in Step 1 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 4:1) to prepare an N-type SnO2 mesoporous microsphere dispersion with a concentration of 1.5 wt%. The dispersion was sprayed onto the TiO2 nanocrystalline particle layer prepared in step 4, which was placed on a heating plate at 100°C. The air spraying parameters were as follows: The distance between the nozzle and the TiO2 nanocrystal particle layer was 15 cm, the dispersion flow rate was 0.10 mL / min, the scanning speed was 5 mm / s, and the number of scans was 4. Afterwards, continue heating for 30 minutes to dry, and obtain N-type SnO2 mesoporous microspheres; Step 6: Disperse the 250 nm ZrO2 cubic nanoframework particles prepared in step 2 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 4:1) to prepare a ZrO2 cubic nanoframework particle dispersion with a concentration of 1.5 wt%. The dispersion was sprayed onto the N-type SnO2 mesoporous microsphere layer prepared in step 5 and placed on a heating plate at 100℃. The air spraying parameters were: the distance between the nozzle and the N-type SnO2 mesoporous microsphere layer was 15 cm, the dispersion flow rate was 0.15 mL / min, the scanning speed was 5 mm / s, and the number of scans was 3. Afterwards, continue heating for 30 minutes to dry, and obtain a ZrO2 cubic nanoframework particle layer; Step 7: Disperse the 150 nm P-type NiO mesoporous microspheres prepared in step 3 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 4:1) to prepare a 1.5 wt% P-type NiO mesoporous microsphere dispersion. The dispersion was sprayed onto the ZrO2 cubic nanoframework particle layer prepared in step 6 and placed on a heating plate at 100°C. The air spraying parameters were: the distance between the nozzle and the ZrO2 cubic nanoframework particle layer was 15 cm, the dispersion flow rate was 0.10 mL / min, the scanning speed was 5 mm / s, and the number of scans was 4. Subsequently, the sample was sintered in an air atmosphere at 500 °C for 30 minutes to obtain a battery skeleton consisting of a TiO2 dense layer (20 nm), a mesoscopic electron transport layer (500 nm), a submicron porous insulating framework layer (0.6 μm), and a mesoscopic hole transport layer (500 nm) sequentially stacked on a conductive glass conductive layer.

[0030] Step 8: Using spin coating at 10,000 rpm, fill the mesopores and submicron pores within the battery framework prepared in Step 7 with dimethylammonium iodide (DMAI) to assist in the formation of a black phase β-CsPbI3 perovskite light-absorbing layer precursor solution (solute molar ratio: CsI:PbI2:DMAI = 1:1:1.2, solvent N,N-dimethylformamide / dimethyl sulfoxide volume ratio 9:1, total cation Cs + +Pb 2+The carbon electrode (20 μm) was prepared by screen printing commercially available carbon paste onto the hole transport layer of the mesoscopic structure after soaking in chlorobenzene for 5 minutes at a concentration of 1.46 mol / L. Then, it was heat-treated at 100 °C for 10 minutes and 250 °C for 5 minutes to obtain a double mesoscopic structure CsPbI3 all-inorganic perovskite solar cell.

[0031] II. Performance Testing This invention discloses a dual-mesoscopic structure all-inorganic perovskite solar cell. Compared with traditional mesoscopic structure all-inorganic perovskite solar cells, the submicron porous insulating framework layer significantly increases the grain size of the light-absorbing layer. Furthermore, the insertion of a mesoscopic hole transport layer between the traditional all-inorganic perovskite / carbon electrodes creates excellent interfacial contact, significantly reduces interfacial defects, and substantially improves hole extraction capability. A 1 cm⁻¹ solar cell was fabricated. 2 The photoelectric conversion efficiency of CsPbI3 all-inorganic perovskite solar cells with a dual mesoscopic structure reaches 14.5%~16.5%.

[0032] Test method: Dual mesoscopic structure CsPbI3 all-inorganic perovskite solar cell J-V Characteristic curve testing was performed using a solar simulator (SS-F5-3A, manufactured by Kuang Yen Technology, Taiwan) equipped with a Keithley 2400 digital source meter. The light source was set to the standard AM 1.5G solar spectrum with a light intensity of 100 mW·cm². -2 Before each test, the simulator's light intensity is precisely calibrated using a certified standard silicon reference cell, and the irradiance is confirmed using a calibration spectrometer. J-V The curve's scan range is set to 0.2 V to 1.2 V, using forward scan ( (0.2 V → 1.2 V). The voltage step size for the test was set to 20 mV, and the delay time was 10 ms.

[0033] Long-term stability data are obtained by testing the photoelectric conversion efficiency of the device after it has been exposed to standard simulated sunlight for 1000 hours, and then comparing it with the initial efficiency to calculate the percentage.

[0034] Test data: The following shows 5 sets of data that passed. J-V Test results V oc , J sc , FF And PCE data. The test results are shown in Table 2 below. Meanwhile, the efficiency of this group of devices remains at 90% of its initial value after 1000 hours of continuous exposure to standard simulated sunlight.

[0035] Table 2. Devices in Example 2 pass... J-VThe four photoelectric performance parameters obtained from the test

[0036] As shown in Table 2 above, the open-circuit voltage of all five groups of devices in Example 2 is greater than 1.05V, and the short-circuit current generally exceeds 19.50mA·cm. -2 The fill factor exceeds 70.50%, and the photoelectric conversion efficiency reaches a maximum of 15.79% and a minimum of 14.80%, exhibiting good overall performance and high repeatability. Compared to Example 1, Example 2 uses a CsPbI3 triiodine system as the perovskite light-absorbing layer, with a band gap of 1.73 eV smaller than that of CsPbI2Br in Example 1 (1.92 eV). Therefore, the open-circuit voltage is lower than that of Example 1. CsPbI3 has a smaller band gap and a wider absorption spectrum, resulting in a higher short-circuit current than the cell in Example 1. The overall photoelectric performance of Example 2 is stable, with good repeatability and excellent long-term stability data. However, it is still inferior to Example 1 mainly because the stability of CsPbI3 itself is lower than that of CsPbI2Br.

[0037] Comparative Example 1 Compared with Example 1, Comparative Example 1 is a carbon electrode CsPbI2Br all-inorganic perovskite solar cell with a mesoscopic structure and no hole transport layer. A dense layer made of TiO2 nanocrystal particles, a mesoscopic electron transport layer made of SnO2 nanocrystal particles self-assembled N-type mesoporous microspheres, a CsPbI2Br all-inorganic perovskite light absorption layer, and a carbon electrode coated on the upper surface of the CsPbI2Br layer are stacked sequentially on conductive glass to obtain the target device.

[0038] I. Preparation This comparative example demonstrates the fabrication of a mesoscopically structured, hole-transport layer-free, carbon electrode CsPbI2Br all-inorganic perovskite solar cell, comprising the following steps: Step 1: Disperse SnO2 nanocrystals with an oleylamine ligand and a particle size of 5 nm in toluene to prepare a SnO2 nanocrystal dispersion with a concentration of 10 mg / mL. Prepare a deionized water: SnO2 nanocrystal particle toluene dispersion with a volume ratio of 15:1. Under the combined action of stirring (3000 rpm) and ultrasound (180W), slowly add the SnO2 nanocrystal particle toluene dispersion to the deionized water. After emulsification for 30 minutes, a semi-transparent ultra-micro emulsion is obtained. Add 4 times the volume of the ultraemulsion to an ethanol / acetone (volume ratio 1:4) mixture to break the emulsion, centrifuge at 10,000 rpm for 30 minutes, and collect the centrifuge. Add 10 times the volume of the centrifuge to an acetonitrile solution of NOBF4 (concentration 5 mg / mL), stir at 3,000 rpm for 60 minutes to remove the oleylamine ligand, and centrifuge again at 10,000 rpm for 30 minutes. Collect the centrifuge to obtain 100 nm N-type SnO2 mesoporous microspheres.

[0039] Step 2: Disperse TiO2 nanocrystals with an oleic acid ligand and a particle size of 3.6 nm in n-hexane to prepare a TiO2 nanocrystal dispersion with a concentration of 0.1 wt%. The conductive glass was placed on a 50°C heating plate, and then a hexane dispersion of TiO2 nanocrystal particles was sprayed onto the conductive layer of the conductive glass. The air spraying parameters were: 12 cm distance between the nozzle and the conductive layer, 0.02 mL / min flow rate of the dispersion, 10 mm / s scanning speed, and 4 scans. After that, the glass was heated for 30 minutes to dry, and a TiO2 nanocrystal particle layer was obtained. Step 3: Disperse the 100 nm N-type SnO2 mesoporous microspheres prepared in Step 1 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 5:2) to prepare an N-type SnO2 mesoporous microsphere dispersion with a concentration of 1.0 wt%. The dispersion was sprayed onto the TiO2 nanocrystalline particle layer prepared in step 4 and placed on a heating plate at 100℃. The air spraying parameters were: the distance between the nozzle and the TiO2 nanocrystalline particle layer was 15 cm, the dispersion flow rate was 0.05 mL / min, the scanning speed was 4 mm / s, and the number of scans was 2. Afterwards, continue heating for 30 minutes to dry, and obtain N-type SnO2 mesoporous microspheres; The sample was then sintered at 450 °C in an air atmosphere for 30 minutes to obtain an electron transport layer consisting of a dense TiO2 layer (20 nm) and a mesoscopic SnO2 layer (300 nm).

[0040] Step 4: Spin-coating the electron transport layer prepared in Step 3 with a CsPbI2Br perovskite light absorption layer precursor solution (solute molar ratio: CsI:PbI2:PbBr2 = 2:1:1, solvent: dimethyl sulfoxide, total cations: Cs) at a speed of 10,000 rpm. + +Pb 2+A CsPbI2Br light-absorbing layer was generated by soaking the CsPbI2Br layer in chlorobenzene for 5 minutes (concentration 1.0 mol / L). A commercially available carbon paste was then screen-printed onto the CsPbI2Br layer to prepare a carbon electrode (20 μm). Subsequently, the electrode was heat-treated at 100 °C for 10 minutes and then at 250 °C for 5 minutes to obtain a CsPbI2Br all-inorganic perovskite solar cell with a mesoscopic structure and no hole transport layer.

[0041] II. Performance Testing Compared to Example 1, this comparative mesoscopic carbon electrode CsPbI2Br all-inorganic perovskite solar cell without a hole transport layer lacks both an insulating framework layer and a hole transport layer. Due to the absence of a hole extraction layer, interlayer recombination between the carbon electrode and CsPbI2Br is more severe, resulting in a 1 cm... 2 The device has a photoelectric conversion efficiency of 11.5%~12.5%.

[0042] Test method: Mesoscopic structure, hole transport layer-free carbon electrode CsPbI2Br all-inorganic perovskite solar cell J- V Characteristic curve testing was performed using a solar simulator (SS-F5-3A, manufactured by Kuang Yen Technology, Taiwan) equipped with a Keithley 2400 digital source meter. The light source was set to the standard AM 1.5G solar spectrum with a light intensity of 100 mW·cm². -2 Before each test, the simulator's light intensity is precisely calibrated using a certified standard silicon reference cell, and the irradiance is confirmed using a calibration spectrometer. J-V The curve's scan range is set to 0.2 V to 1.2 V, using forward scan ( (0.2 V → 1.2 V). The voltage step size for the test was set to 20 mV, and the delay time was 10 ms.

[0043] Long-term stability data are obtained by testing the photoelectric conversion efficiency of the device after it has been exposed to standard simulated sunlight for 1000 hours, and then comparing it with the initial efficiency to calculate the percentage.

[0044] Test data: The following shows 5 sets of data that passed. J-V Test results V oc , J sc , FF The PCE test results are shown in Table 3 below. Furthermore, after 1000 hours of continuous exposure to standard simulated sunlight, the efficiency of this group of devices remains at 94% of its initial value.

[0045] Table 3 shows the device in Comparative Example 1 passing... J-VThe four photoelectric performance parameters obtained from the test

[0046] As shown in Table 3 above, in the five sets of photoelectric performance data for Comparative Example 1, the open-circuit voltage is >1.10 V and the short-circuit current is >14.00 mA·cm. -2 The fill factor is >70%, and the photoelectric conversion efficiency is between 11.5% and 12.5%, with small overall fluctuations and good repeatability. The long-term stability data is also excellent, stemming from the inherent superior stability of the CsPbI₂Br all-inorganic perovskite. Compared to Example 1, the open-circuit voltage and fill factor of the device are generally lower because this comparative device lacks a hole transport layer. It relies on the work function difference between the carbon electrode and CsPbI₂Br to extract holes, and the extraction efficiency cannot be compared with devices with a hole transport layer. This indicates that constructing a complete functional layer is an effective method for obtaining high-efficiency carbon electrode all-inorganic perovskite solar cells.

[0047] Comparative Example 2 The difference between this comparative example and Example 1 is that Comparative Example 2 does not have a hole transport layer. Comparative Example 2 involves preparing an electron transport layer on conductive glass, a submicron porous insulating framework layer made of ZrO2 cubic nanoframework particles filled with all-inorganic perovskite, and then directly preparing a carbon electrode.

[0048] The difference between this comparative example and comparative example 1 is that comparative example 2 adds a submicron porous insulating framework layer made of ZrO2 cubic nanoframework particles to the perovskite light-absorbing layer of the traditional mesoscopic all-inorganic perovskite solar cell of comparative example 1.

[0049] The impact on battery performance was investigated by comparing it with Comparative Example 1. Furthermore, it was compared with Example 1 to investigate whether the insulating frame layer affected the device's photoelectric performance.

[0050] Specifically, I. Preparation This invention discloses a method for fabricating a dual-mesoscopic structure all-inorganic perovskite solar cell, comprising the following steps: Step 1: Disperse SnO2 nanocrystals with an oleylamine ligand and a particle size of 5 nm in toluene to prepare a SnO2 nanocrystal dispersion with a concentration of 10 mg / mL. Prepare a deionized water: SnO2 nanocrystal particle toluene dispersion with a volume ratio of 15:1. Under the combined action of stirring (3000 rpm) and ultrasound (180W), slowly add the SnO2 nanocrystal particle toluene dispersion to the deionized water. After emulsification for 30 minutes, a semi-transparent ultra-micro emulsion is obtained. Add 4 times the volume of the ultraemulsion to an ethanol / acetone (volume ratio 1:4) mixture to break the emulsion, centrifuge at 10,000 rpm for 30 minutes, and collect the centrifuge. Add 10 times the volume of the centrifuge to an acetonitrile solution of NOBF4 (concentration 5 mg / mL), stir at 3,000 rpm for 60 minutes to remove the oleylamine ligand, and centrifuge again at 10,000 rpm for 30 minutes. Collect the centrifuge to obtain 100 nm N-type SnO2 mesoporous microspheres.

[0051] Step 2: Prepare a 5 mg / mL zirconium dichlorocerocene acetone solution. Add a 25 wt% ammonia solution to the zirconium dichlorocerocerocene acetone solution, controlling the volume ratio of ammonia solution to zirconium dichlorocerocerocene acetone solution to 1:15. Transfer the obtained suspension to a high-pressure reactor with a polytetrafluoroethylene liner, heat-treat at 200℃ for 12 hours, cool naturally to room temperature, centrifuge at 6000 rpm for 15 minutes, collect the centrifuged material, and obtain 250 nm ZrO2 cubic nanoframework particles.

[0052] Step 3: Disperse TiO2 nanocrystals with an oleic acid ligand and a particle size of 3.6 nm in n-hexane to prepare a TiO2 nanocrystal dispersion with a concentration of 0.1 wt%. The conductive glass was placed on a 50°C heating plate, and then a hexane dispersion of TiO2 nanocrystal particles was sprayed onto the conductive layer of the conductive glass. The air spraying parameters were: 12 cm distance between the nozzle and the conductive layer, 0.02 mL / min flow rate of the dispersion, 10 mm / s scanning speed, and 4 scans. After that, the glass was heated for 30 minutes to dry, and a TiO2 nanocrystal particle layer was obtained. Step 4: Disperse the 100 nm N-type SnO2 mesoporous microspheres prepared in Step 1 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 5:2) to prepare an N-type SnO2 mesoporous microsphere dispersion with a concentration of 1.0 wt%. The dispersion was sprayed onto the TiO2 nanocrystalline particle layer prepared in step 3, which was placed on a heating plate at 100°C. The air spraying parameters were: the distance between the nozzle and the TiO2 nanocrystalline particle layer was 15 cm, the dispersion flow rate was 0.05 mL / min, the scanning speed was 4 mm / s, and the number of scans was 2. Afterwards, continue heating for 30 minutes to dry, and obtain N-type SnO2 mesoporous microspheres; Step 5: Disperse the 250 nm ZrO2 cubic nanoframework particles prepared in step 2 in anhydrous ethanol / ethylene glycol monomethyl ether (volume ratio 5:2) to prepare a ZrO2 cubic nanoframework particle dispersion with a concentration of 2.0 wt%. The dispersion was sprayed onto the N-type SnO2 mesoporous microsphere layer prepared in step 4, which was placed on a heating plate at 100℃. The air spraying parameters were: the distance between the nozzle and the N-type SnO2 mesoporous microsphere layer was 15 cm, the dispersion flow rate was 0.15 mL / min, the scanning speed was 5 mm / s, and the number of scans was 4. After that, the mixture was heated for 30 minutes to dry, and a ZrO2 cubic nanoframework particle layer was obtained. Subsequently, the sample was sintered at 450 °C in an air atmosphere for 30 minutes to obtain a half-cell skeleton consisting of a TiO2 dense layer (20 nm), a mesoscopic electron transport layer (300 nm), and a submicron porous insulating framework layer (0.7 μm) sequentially stacked on a conductive glass conductive layer.

[0053] Step 6: Using a spin-coating method at a speed of 10,000 rpm, fill the mesopores and submicron pores within the half-cell framework prepared in Step 5 with a CsPbI2Br perovskite light-absorbing layer precursor solution (solute molar ratio: CsI:PbI2:PbBr2 = 2:1:1, solvent: dimethyl sulfoxide, total cations: CsI2, PbI2, PbBr2 = 2:1 ... + +Pb 2+ A CsPbI2Br layer was generated by soaking the sample in chlorobenzene for 5 minutes at a concentration of 1.0 mol / L. A commercially available carbon paste was then screen-printed onto the CsPbI2Br layer to prepare a carbon electrode (20 μm). Subsequently, the sample was heat-treated at 100 °C for 10 minutes and then at 250 °C for 5 minutes to obtain a CsPbI2Br all-inorganic perovskite solar cell with a mesoscopic structure containing an insulating framework layer and no hole transport layer.

[0054] II. Performance Testing This comparative example involves inserting an insulating framework layer into the light-absorbing layer of a conventional mesoscopic carbon electrode CsPbI2Br all-inorganic perovskite solar cell without a hole transport layer to investigate its impact on cell performance. A 1 cm [structure / section / data] was prepared. 2 The photoelectric conversion efficiency of this CsPbI2Br all-inorganic perovskite solar cell is in the range of 11.5% to 12.5%.

[0055] Test method: CsPbI2Br all-inorganic perovskite solar cells with insulating framework layer J-V Characteristic curve testing was performed using a solar simulator (SS-F5-3A, manufactured by Kuang Yen Technology, Taiwan) equipped with a Keithley 2400 digital source meter. The light source was set to the standard AM 1.5G solar spectrum with a light intensity of 100 mW·cm². -2 Before each test, the simulator's light intensity is precisely calibrated using a certified standard silicon reference cell, and the irradiance is confirmed using a calibration spectrometer. J-V The curve's scan range is set to 0.2 V to 1.2 V, using forward scan ( (0.2 V → 1.2 V). The voltage step size for the test was set to 20 mV, and the delay time was 10 ms.

[0056] Long-term stability data are obtained by testing the photoelectric conversion efficiency of the device after it has been exposed to standard simulated sunlight for 1000 hours, and then comparing it with the initial efficiency to calculate the percentage.

[0057] Test data: The following shows 5 sets of data that passed. J-V Test results V oc , J sc , FF The PCE test results are shown in Table 4 below. Furthermore, after 1000 hours of continuous exposure to standard simulated sunlight, the efficiency of this group of devices remains at 96% of its initial value.

[0058] Table 4 Comparative Example 2 Device Passes J-V The four photoelectric performance parameters obtained from the test

[0059] As shown in Table 4 above, in the five sets of photoelectric performance data for Comparative Example 2, the open-circuit voltage is >1.10 V and the short-circuit current is >14.00 mA·cm. -2 The fill factor is >72.50%, and the photoelectric conversion efficiency is between 11.5% and 12.5%, with small overall fluctuations and good repeatability. The long-term stability data is also excellent, stemming from the inherent superior stability of the CsPbI₂Br all-inorganic perovskite. Compared to Comparative Example 1, the device's photoelectric performance did not change significantly, indicating that the introduction of the insulating framework layer does not lead to a decrease in photoelectric performance. The slight increase in fill factor is due to improved interface contact after the introduction of the insulating framework layer. However, the overall photoelectric performance is inferior to that of Example 1, demonstrating that constructing a complete functional layer is an effective method for obtaining high-efficiency carbon electrode all-inorganic perovskite solar cells.

[0060] The above embodiments and accompanying drawings are not intended to limit the product form and preparation method of the present invention. Any appropriate changes or modifications made by those skilled in the art should be considered as not departing from the patent scope of the present invention.

Claims

1. A method for fabricating a dual-mesoscopic structure all-inorganic perovskite solar cell, characterized in that: Includes the following steps: Step 1: Disperse SnO2 nanocrystals with an oleylamine ligand and a particle size of 5-10 nm in toluene to prepare a SnO2 nanocrystal dispersion with a concentration of 10-50 mg / mL. Prepare a deionized water: SnO2 nanocrystal particle toluene dispersion with a volume ratio of 15~20:

1. Under the combined action of stirring and ultrasound, add the SnO2 nanocrystal particle toluene dispersion dropwise to the deionized water. After emulsification for 15~30 minutes, a transparent or semi-transparent ultra-micro emulsion is obtained. Add 2 to 4 times the volume of the ethanol / acetone mixture to the ultra-microemulsion to break the emulsion. The volume ratio of ethanol to acetone is 1:1 to 1:

4. Centrifuge at 6000 to 10000 rpm for 15 to 30 minutes and collect the centrifuged material. Add 5-10 times the volume of the centrifuged material to a NOBF4 acetonitrile solution with a concentration of 5-10 mg / mL. Stir at 2000-3000 rpm for 30-60 minutes to remove the oleylamine ligand. Then centrifuge at 6000-10000 rpm for 15-30 minutes. Collect the centrifuged material to obtain 50-150 nm N-type SnO2 mesoporous microspheres. Step 2: Prepare a 2.5-5 mg / mL zirconium dichlorocerocene acetone solution. Add a 25 wt% ammonia solution to the zirconium dichlorocerocerocene acetone solution, controlling the volume ratio of ammonia solution to zirconium dichlorocerocerocene acetone solution to be 1 / 60-1 / 15. Transfer the obtained suspension to a high-pressure reactor with a polytetrafluoroethylene liner. Heat-treat at 180-200℃ for 6-12 hours, cool naturally to room temperature, and centrifuge at 6000-10000 rpm for 15-30 minutes. Collect the centrifuged material to obtain 150-250 nm ZrO2 cubic nanoframework particles. Step 3: Disperse NiO nanocrystals with a particle size of 5-10 nm and containing oleylamine ligands in toluene to prepare a NiO nanocrystal dispersion with a concentration of 10-50 mg / mL. Prepare a deionized water: NiO nanocrystal particle toluene dispersion with a volume ratio of 15~20:

1. Under the combined action of stirring and ultrasound, add the NiO nanocrystal particle toluene dispersion dropwise to the deionized water. After emulsification for 15~30 minutes, a transparent or semi-transparent ultra-micro emulsion is obtained. Add 2 to 4 times the volume of the ethanol / acetone mixture to the ultra-microemulsion to break the emulsion. The volume ratio of ethanol to acetone is 1:1 to 1:

4. Centrifuge at 6000 to 10000 rpm for 15 to 30 minutes and collect the centrifuged material. Add 5-10 times the volume of the centrifuged material to a NOBF4 acetonitrile solution with a concentration of 5-10 mg / mL. Stir at 2000-3000 rpm for 30-60 minutes to remove the oleylamine ligand. Then centrifuge at 6000-10000 rpm for 15-30 minutes. Collect the centrifuged material to obtain 50-150 nm P-type NiO mesoporous microspheres. Step 4: Disperse TiO2 nanocrystals with a particle size of 3-5 nm and containing oleic acid ligands in n-hexane to prepare a TiO2 nanocrystal dispersion with a concentration of 0.1-0.5 wt%. The conductive glass was placed on a heating plate at 50~100℃, and then the TiO2 nanocrystalline particles n-hexane dispersion was sprayed onto the conductive layer of the conductive glass. The air spraying parameters were: the distance between the nozzle and the conductive layer was 12~15 cm, the dispersion flow rate was 0.02~0.05 mL / min, the scanning speed was 8~15 mm / s, and the number of scans was 4~8. Afterwards, continue heating for 15-30 minutes to dry, and obtain a TiO2 nanocrystalline particle layer; Step 5: Disperse the N-type SnO2 mesoporous microspheres with a particle size of 50~150 nm prepared in Step 1 in anhydrous ethanol / ethylene glycol monomethyl ether with a volume ratio of 4:1~5:2 to prepare an N-type SnO2 mesoporous microsphere dispersion with a concentration of 1.0~3.0wt%. The dispersion was sprayed onto the TiO2 nanocrystalline particle layer prepared in step 4, which was placed on a heating plate at 50~100℃. The air spraying parameters were: the distance between the nozzle and the TiO2 nanocrystalline particle layer was 10~15 cm, the dispersion flow rate was 0.05~0.15 mL / min, the scanning speed was 3~6 mm / s, and the number of scans was 2~4. Afterwards, continue heating for 15-30 minutes to dry, and obtain N-type SnO2 mesoporous microspheres; Step 6: Disperse the ZrO2 cubic nanoframework particles with a particle size of 150~250 nm prepared in step 2 in anhydrous ethanol / ethylene glycol monomethyl ether with a volume ratio of 4:1~5:2 to prepare a ZrO2 cubic nanoframework particle dispersion with a concentration of 1.5~3.0 wt%. The dispersion was sprayed onto the N-type SnO2 mesoporous microsphere layer prepared in step 5, which was placed on a heating plate at 50~100℃. The air spraying parameters were: the distance between the nozzle and the N-type SnO2 mesoporous microsphere layer was 10~15 cm, the dispersion flow rate was 0.1~0.2 mL / min, the scanning speed was 2~8 mm / s, and the number of scans was 3~6. Afterwards, continue heating for 15-30 minutes to dry, and obtain a ZrO2 cubic nanoframework particle layer; Step 7: Disperse the P-type NiO mesoporous microspheres with a particle size of 50~150 nm prepared in step 3 in anhydrous ethanol / ethylene glycol monomethyl ether with a volume ratio of 4:1~5:2 to prepare a P-type NiO mesoporous microsphere dispersion with a concentration of 1.0~3.0wt%. The dispersion was sprayed onto the ZrO2 cubic nanoframework particle layer prepared in step 6, which was placed on a heating plate at 50~100℃. The air spraying parameters were: the distance between the nozzle and the ZrO2 cubic nanoframework particle layer was 10~15 cm, the dispersion flow rate was 0.05~0.15 mL / min, the scanning speed was 3~6 mm / s, and the number of scans was 2~4. Then, the sample was sintered in an air atmosphere at 400~500 °C for 30~60 minutes to obtain a battery skeleton, which includes a TiO2 dense layer, a mesoscopic electron transport layer, a submicron porous insulating framework layer and a mesoscopic hole transport layer stacked sequentially on a conductive glass conductive layer. Step 8: Fill the mesopores and submicron pores within the battery framework prepared in Step 7 with CsPbI using spin coating at a speed of 8000~12000 rpm. 3-x Br x The perovskite light-absorbing layer precursor solution is soaked in chlorobenzene or ethyl acetate for 5-10 minutes; Carbon electrodes are then screen-printed onto the hole transport layer of the mesoscopic structure, and the cells are heat-treated at 100~250 ℃ for 10~30 minutes to obtain a fully inorganic perovskite solar cell with a dual mesoscopic structure.

2. The method for fabricating a dual-mesoscopic structure all-inorganic perovskite solar cell as described in claim 1, characterized in that: In the battery skeleton, the thickness of the TiO2 dense layer is 15~25 nm, the thickness of the mesoscopic electron transport layer is 150~300 nm, the thickness of the submicron porous insulating framework layer is 0.5~1 μm, and the thickness of the mesoscopic hole transport layer is 150~300 nm.

3. A fully inorganic perovskite solar cell with a dual mesoscopic structure obtained by the preparation method according to claim 1, characterized in that: It includes a conductive glass conductive layer, a battery frame, and a carbon electrode printed on the battery frame by screen printing; The battery skeleton is filled with CsPbI. 3-x Br x All-inorganic perovskite light-absorbing layer; The battery framework comprises a TiO2 dense layer, a mesoscopic electron transport layer, a submicron porous insulating framework layer, and a mesoscopic hole transport layer sequentially stacked on the conductive glass conductive layer. The battery framework has mesopores and submicron pores. The CsPbI... 3-x Br x The all-inorganic perovskite light-absorbing layer penetrates and spreads within the mesopores and submicron pores, and the carbon electrode is coated on the mesoscopic hole transport layer. The mesoscopic electron transport layer is prepared by self-assembly of 5-10 nm SnO2 nanocrystals to form 50-150 nm N-type mesoporous microspheres. The submicron porous insulating framework layer is prepared by 150-250 nm ZrO2 cubic nanoframework particles. The mesoscopic hole transport layer is prepared by self-assembly of 5-10 nm NiO nanocrystals to form 50-150 nm P-type mesoporous microspheres.

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