Perovskite solar cell

Abstract

The application discloses a perovskite solar cell. The perovskite solar cell comprises a perovskite light absorption layer and an interface modification layer arranged on the upper portion of the perovskite light absorption layer, and the interface modification layer is prepared by the reaction of a silane coupling agent and a metal alkoxide. The silane coupling agent and the metal alkoxide are used as the interface modification layer, so that the performance attenuation of the perovskite solar cell caused by water vapor can be effectively prevented. The interface modification layer can improve the efficiency of the perovskite solar cell and the stability of the perovskite solar cell.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar energy utilization, and in particular to a perovskite solar cell. BACKGROUND

[0002] In the past decade, perovskite solar cells have stood out among many new types of solar cells, attracting the attention of many researchers, and have been selected by Science as one of the top ten scientific breakthroughs in 2013. The light-absorbing material used in this type of cell has a general formula of ABX3, where A is a +1 valence cation selected from methylamine ion (CH3NH3 + ), ethylamine ion (C2H5NH3 + ), methylether ion (NH2CH=NH2 + ) or Cs + ion, B is a +2 valence metal ion selected from Sn 2+ or Pb 2+ , and X is a halogen ion selected from Cl - , Br - or I - . It is a typical perovskite crystal structure, so this type of cell is called a perovskite solar cell. Because it is in a fully solid state, it can avoid the problems caused by liquid electrolytes and achieve high conversion efficiency. In just a few years, its photoelectric conversion efficiency has increased from 3.8% in 2009 to 25.5% in 2021. This rate of development has never been seen before, and perovskite solar cells have great potential and application prospects.

[0003] However, the perovskite absorber layer in perovskite solar cells is prone to decomposition in the presence of moisture in the air, and its stability is not ideal and needs to be further improved. SUMMARY

[0004] The present application overcomes the problem of poor stability of existing perovskite solar cells. The purpose of the present application is to provide a perovskite solar cell. The present application proposes introducing an interface modification layer between the perovskite light-absorbing layer / electron transport layer or the perovskite light-absorbing layer / hole transport layer. This interface modification layer can not only improve the efficiency of the perovskite solar cell, but also improve the stability of the perovskite solar cell.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows: a perovskite solar cell, comprising a perovskite light-absorbing layer and an interface modification layer disposed on the upper part of the perovskite light-absorbing layer, wherein the interface modification layer is prepared by the reaction of a silane coupling agent and a metal alkoxide.

[0006] The perovskite light-absorbing layer material has a general formula of ABX3, where A is a +1 valence cation selected from methylamine ion (CH3NH3 +ethylamine ion (C2H5NH3 + ), dimethylamine ion (C2H5NH3 + ), or Cs + ion, B is a +2 valence metal ion selected from Sn 2+ or Pb 2+ , X is a halogen ion selected from Cl - , Br - or I - , is a typical perovskite crystal structure.

[0007] Preferably, the interface modification layer is prepared by the following steps:

[0008] (1) dissolving a silane coupling agent in an ethanol or isopropanol solution to obtain an alcohol solution of the silane coupling agent, then adding a metal alkoxide, and mixing uniformly to obtain an interface modification layer solution;

[0009] (2) coating the modification layer solution on the surface of the perovskite light absorption layer, and then heat treating the modification layer solution to obtain the interface modification layer.

[0010] Preferably, the silane coupling agent is an amino-containing silane coupling agent or an amine-containing silane coupling agent.

[0011] Further preferably, the silane coupling agent is selected from one of diethylaminomethyltriethoxysilane, hexanediaminomethyltrimethoxysilane, (3-aminopropyl)diethoxymethylsilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane.

[0012] Preferably, the metal alkoxide is selected from one of tetraethyl orthosilicate, aluminum isopropoxide, butyl titanate, cerium isopropoxide, and lanthanum isopropoxide.

[0013] Preferably, the molar ratio of the silane coupling agent to the metal alkoxide is 1:2-1:10, and the molar concentration of the silane coupling agent in the alcohol solution of the silane coupling agent is 5-50 mmol / L.

[0014] Preferably, the heat treatment temperature in step (2) is 100-150°C, and the heat treatment time is 25-35 minutes.

[0015] Preferably, the coating of the modification layer solution in step (2) is performed by a spin coating method or a soaking method, and the specific conditions of the spin coating method are a spin coating speed of 3000-5000 rpm, a spin coating time of 30-60 s, and the specific conditions of the soaking method are a soaking time of 2-3 min.

[0016] Preferably, the perovskite solar cell specifically comprises a first electrode, an electron transport layer, a perovskite light absorption layer, a hole transport layer and a second electrode which are sequentially stacked, and an interface modification layer is arranged between the perovskite light absorption layer and the hole transport layer.

[0017] Preferably, the perovskite solar cell specifically comprises a first electrode, an electron transport layer, a perovskite light absorption layer, a hole transport layer and a second electrode which are sequentially stacked, and an interface modification layer is arranged between the perovskite light absorption layer and the hole transport layer.

[0018] The first electrode or the second electrode material is a transparent conductive electrode or a metal electrode; the electron transport layer material can be TiO2, SnO2, PCBM (fullerene derivative) and the like; the hole transport layer material can be nickel oxide, PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]), Spiro-OMeTAD (2,2',7,7'-tetra[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene) and the like.

[0019] Compared with the prior art, the perovskite solar cell has the following beneficial effects:

[0020] 1. The interface modification layer prepared by using the silane coupling agent with an amine group or an amino group and a metal alkoxide as the modification layer can coordinate with Pb 2+ of the perovskite absorption layer, thereby passivating the surface dangling bonds of Pb; at the same time, the silane coupling agent and the metal alkoxide can absorb water when encountering a small amount of water, and form an ultrathin oxide barrier layer between the perovskite and the charge transport layer, which can effectively prevent the performance degradation of the perovskite solar cell caused by water vapor.

[0021] 2. The interface modification layer can improve the efficiency and stability of the perovskite solar cell, especially when the interface modification solution is prepared by using diethylaminomethyltriethoxysilane and lanthanum isopropoxide, the stability of the perovskite solar cell is significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is the J-V curve of the perovskite solar cell prepared in Example 1 under the condition that the light source is a solar simulator (standard light source) and the light intensity is 100 mW / cm 2 , wherein J is the photocurrent density and V is the photovoltage. DETAILED DESCRIPTION

[0023] The following examples are further illustrations of the present application and are not intended to limit the present application. Except in the operating and comparative examples, or where otherwise indicated, all ingredients are commercially available and used as received unless otherwise specified. Tin oxide original solution 15wt% means that the mass of tin oxide accounts for the mass fraction of water in the solution.

[0024] A perovskite solar cell, comprising a first electrode (300 nm), an electron transport layer (30-100 nm), a perovskite light absorption layer (600 nm), a hole transport layer (80-150 nm) and a second electrode (80-200 nm) which are sequentially stacked, an interface modification layer is arranged between the perovskite light absorption layer and the hole transport layer, and the thickness of the interface modification layer is 1-5 nm; or comprising a first electrode, a hole transport layer, a perovskite light absorption layer, an electron transport layer and a second electrode which are sequentially stacked, an interface modification layer is arranged between the perovskite light absorption layer and the electron transport layer, and the interface modification layer is prepared by reaction of a silane coupling agent and a metal alkoxide.

[0025] The perovskite light absorption layer material has a general formula of ABX3, wherein A is a +1 valence cation selected from a methylamine ion (CH3NH3 + ), an ethylamine ion (C2H5NH3 + ), a methylether ion (NH2CH=NH2 + ) or a Cs + ion, B is a +2 valence metal ion selected from Sn 2+ or Pb 2+ , and X is a halogen ion selected from Cl - , Br - or I - , and is a typical perovskite crystal structure.

[0026] In the following examples, the preparation method of the perovskite light absorption layer is preferably as follows: 276.6 mg of PbI2 is dissolved in 200 μL of DMSO; 190.8 mg of MAI is dissolved in 300 μL of GBL; heating is performed at 75°C for 1 hour, and after the MAI is completely dissolved, the two solutions are mixed; heating is continued at 60°C for 3 hours and magnetic stirring is performed until complete dissolution; a perovskite thin film is prepared by a hot substrate blade coating method under an atmospheric environment, the temperature of the hot substrate is 150°C, the coating speed is 100 mm / min, and the gap between the doctor blade and the substrate surface is 100 μm.

[0027] The material of the first electrode or the second electrode is a transparent conductive electrode or a metal electrode, and in the following examples, the material of the first electrode is preferably FTO transparent conductive glass, and the material of the second electrode is preferably a gold electrode or a silver electrode; the material of the electron transport layer can be TiO2, SnO2, PCBM (fullerene derivative) or the like; the material of the hole transport layer can be nickel oxide, PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]), Spiro-OMeTAD (2,2',7,7'-tetra[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene) or the like.

[0028] In the following preferred embodiment, the interface modification layer is prepared by the following steps:

[0029] (1) Dissolve the silane coupling agent in an ethanol or isopropanol solution to obtain an alcohol solution of the silane coupling agent, then add a metal alkoxide, mix uniformly to obtain an interface modification layer solution;

[0030] (2) Coat the modification layer solution on the surface of the perovskite light absorption layer, and then heat treat the modification layer solution to obtain the interface modification layer.

[0031] In the following preferred embodiment, the silane coupling agent is an amino-containing silane coupling agent or an amine-containing silane coupling agent. Further preferably, the silane coupling agent is selected from one of diethylaminomethyltriethoxysilane, hexanediaminomethyltrimethoxysilane, (3-aminopropyl)diethoxymethylsilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane. The metal alkoxide is selected from one of tetraethyl orthosilicate, aluminum isopropoxide, butyl titanate, cerium isopropoxide, and lanthanum isopropoxide.

[0032] In the following preferred embodiment, the molar ratio of the silane coupling agent to the metal alkoxide is 1:2-10, and the molar concentration of the silane coupling agent in the alcohol solution of the silane coupling agent is 5-50 mmol / L. Further preferably, the molar ratio of the silane coupling agent to the metal alkoxide is 1:2-5, and the molar concentration of the silane coupling agent in the alcohol solution of the silane coupling agent is 20-50 mmol / L.

[0033] In the following preferred embodiment, the heat treatment temperature in step (2) is 100-150°C, and the heat treatment time is 25-35 minutes. Further preferably, the heat treatment temperature in step (2) is 120°C, and the heat treatment time is 30 minutes.

[0034] In the following preferred embodiment, the coating of the modification layer solution in step (2) is performed by a spin coating method or a soaking method. The specific conditions of the spin coating method are a spin coating speed of 5000 rpm and a spin coating time of 50 s.

[0035] In the following preferred embodiment of the perovskite solar cell, the perovskite solar cell is prepared by the following steps:

[0036] (1) Ultrasonically clean the substrate with the first electrode with a mixed solution of deionized water and glass cleaner, deionized water, ethanol, and isopropanol, for 15-20 minutes, and then perform ultraviolet ozone treatment for 15-20 minutes;

[0037] (2) Prepare an electron transport layer on the first electrode layer by a spin coating process at a speed of 3000-5000 rpm for 30 s, and then anneal the substrate at 100-150°C for 30-60 minutes;

[0038] (3) UV-ozone treatment of the electron transport layer for 15-20 min, deposition of the perovskite precursor on the electron transport layer by doctor blade or spin coating process, and then crystallization into a film by annealing (perovskite light absorption layer). The hot substrate temperature is 150°C, the doctor blade speed is 100-2000 mm / min, the gap between the doctor blade and the substrate surface is 100 pm. The spin coating speed is 3000-5000 rpm, the spin coating time is 30-60 s, the annealing temperature is 110-150°C, and the annealing time is 10-20 min;

[0039] (4) Preparation of an interface modification layer on the surface of the perovskite film by spin coating or immersion process, spin coating speed 3000-5000 rpm, spin coating time 30-60 s, immersion time 2-3 min;

[0040] (5) Deposition of a hole transport layer on the surface of the interface modification layer by spin coating process, spin coating speed 3000-5000 rpm, spin coating time 30-60 s;

[0041] (6) Preparation of a second electrode layer on the hole transport layer by vacuum evaporation.

[0042] or prepared by the following steps:

[0043] (1) Ultrasonic cleaning of the substrate with the first electrode with a mixed solution of deionized water and glass cleaner, deionized water, ethanol, isopropanol, ultrasonic time 15-20 min, UV-ozone treatment for 15-20 min;

[0044] (2) Preparation of a hole transport layer on the first electrode layer by spin coating process, speed 3000-5000 rpm, time 30-60 s, and then annealing at 100-150°C substrate for 30-60 min;

[0045] (3) UV-ozone treatment of the hole transport layer for 15-20 min, deposition of the perovskite precursor on the hole transport layer by doctor blade or spin coating process, and then crystallization into a film by annealing (perovskite light absorption layer), doctor blade speed 100-2000 mm / min, spin coating speed 3000-5000 rpm, spin coating time 30-60 s, annealing temperature 110-150°C, annealing time 10 min;

[0046] (4) Preparation of an interface modification layer on the surface of the perovskite film by spin coating or immersion process, spin coating speed 3000 rpm, spin coating time 30 s, immersion time 2-3 min;

[0047] (5) Deposition of an electron transport layer on the surface of the interface modification layer by spin coating process, spin coating speed 3000-5000 rpm, spin coating time 30-60 s;

[0048] (6) A second electrode layer is prepared on the electron transport layer by vacuum evaporation.

[0049] Example 1

[0050] A perovskite solar cell is prepared by the following steps:

[0051] (1) Clean the transparent conductive glass: ultrasonically clean the transparent conductive glass with a mixed solution of deionized water and glass cleaner, deionized water, ethanol, and isopropanol, respectively, for 15 minutes, and then treat it with ultraviolet ozone for 15 minutes to obtain clean FTO transparent conductive glass. The conductive film of the FTO transparent conductive glass has a thickness of 300 nm.

[0052] (2) Prepare an electron transport layer on the FTO transparent conductive glass by a spin coating process: weigh 500 mg of tin oxide stock solution (15 wt%) and add 2.5 mL of deionized water, and then shake gently; prepare a tin oxide nanocrystalline film by spin coating at a speed of 4000 rpm for 30 seconds, and then anneal it at 150°C for 30 minutes. The thickness of the electron transport layer is 65 nm.

[0053] (3) Ultraviolet ozone treat the electron transport layer for 15 minutes, deposit a perovskite precursor on the electron transport layer by a doctor blade coating process, and then crystallize it into a film (perovskite light absorption layer) by annealing: dissolve 276.6 mg of PbI2 in 200 μL of DMSO; dissolve 190.8 mg of MAI in 300 μL of GBL; heat at 75°C for 1 hour, and then mix the two solutions after MAI is completely dissolved; continue to heat at 60°C for 3 hours and magnetically stir until completely dissolved; prepare a perovskite film by a hot substrate doctor blade coating method in an atmospheric environment, with a hot substrate temperature of 150°C, a coating speed of 100 mm / min, a gap between the doctor blade and the substrate surface of 100 μm, a spin coating speed of 4000 rpm, a spin coating time of 45 seconds, an annealing temperature of 130°C, and an annealing time of 15 minutes. The thickness of the perovskite light absorption layer is 600 nm.

[0054] (4) Prepare an interface modification layer on the surface of the perovskite film: dissolve diethylaminomethyl triethoxysilane in ethanol to prepare a 20 mmol / L diethylaminomethyl triethoxysilane ethanol solution, and then add lanthanum isopropoxide. The molar ratio of diethylaminomethyl triethoxysilane to lanthanum isopropoxide is 1 / 5. After mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 seconds, and then heat treated at a temperature of 120°C for 30 minutes. The thickness of the interface modification layer is 3 nm.

[0055] (5) Depositing hole transport layer on the surface of interface modification layer: hole transport layer material (Spiro-OMeTAD solution) is spin-coated at a speed of 4000 rpm for 45 s to form a film, wherein the preparation method of Spiro-OMeTAD solution is as follows: 72.3 mg of Spiro-OMeTAD is added into 1 mL of chlorobenzene, stirred until clear, and then 28.8 μL of TBP and 17.5 μL of Li-TFSI solution are added and stirred for 1 min, and the thickness of the hole transport layer is 100 nm.

[0056] (6) Finally, a thermal evaporation technique is used, and when the vacuum degree reaches 2.0 x 10 -3 Pa, the film coating starts, wherein the deposition rate is 0.15 nm / s when stable, and the deposition is stopped immediately after the display shows 140 nm, and a 140 nm gold electrode is obtained by evaporation. Finally, a perovskite solar cell is obtained.

[0057] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell is measured to be 21.5% (as shown in Figure 1 . After being placed in a humidity of 30% for 90 days, the photoelectric conversion efficiency is tested to be 20.3%.

[0058] Comparative Example 1

[0059] The same as Example 1, except that no interface modification layer is prepared on the surface of the perovskite film.

[0060] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The perovskite solar cell obtained in Comparative Example 1 is tested, and after being placed in a humidity of 30% for 90 days, it is tested again.

[0061] The comparison of the light conversion efficiency of the perovskite solar cells obtained in Example 1 and Comparative Example 1 is shown in Table 1.

[0062] Table 1 Light conversion efficiency of perovskite solar cells of Example 1 and Comparative Example 1

[0063] 0 days efficiency 90 days efficiency Example 1 21.7％ 20.5％ Comparative Example 1 17.3％ 14.2％

[0064] From Table 1, the light conversion efficiency of the perovskite solar cell obtained by Example 1 is significantly higher than that of Comparative Example 1, the silane coupling agent and the metal alkoxide can absorb moisture when encountering a small amount of moisture, and form an ultrathin oxide barrier layer between the perovskite / charge transport layer, which can effectively prevent the performance degradation of the perovskite solar cell caused by water vapor, the interface modification layer proposed in the present application can not only improve the efficiency of the perovskite solar cell, but also improve the stability of the perovskite solar cell.

[0065] Example 2

[0066] A perovskite solar cell is prepared by the following steps:

[0067] (1) Clean the transparent conductive glass: ultrasonically clean the transparent conductive glass with a mixed solution of deionized water and glass cleaner, deionized water, ethanol, and isopropanol, respectively, for 15 min, and treat with ultraviolet ozone for 15 min to obtain clean FTO transparent conductive glass, and the conductive film thickness of the FTO transparent conductive glass is 300 nm.

[0068] (2) Prepare an electron transport layer on the FTO transparent conductive glass by a spin coating process: weigh 500 mg of tin oxide stock solution (15 wt%) and add 2.5 mL of deionized water, and shake gently; prepare a tin oxide nanocrystalline film by spin coating at a speed of 4000 rpm for 30 s, and finally anneal at 150℃ for 30 min, and the thickness of the electron transport layer is 100 nm.

[0069] (3) Ultraviolet ozone treat the electron transport layer for 20 min, deposit a perovskite precursor on the electron transport layer by a doctor blade coating process, and then crystallize into a film by annealing (perovskite light absorption layer): dissolve 276.6 mg of PbI2 in 200 μL of DMSO; dissolve 190.8 mg of MAI in 300 μL of GBL; heat at 75℃ for 1 hour, and after MAI is completely dissolved, mix the two solutions; continue to heat at 60℃ for 3 hours and magnetically stir until completely dissolved; prepare a perovskite film by a hot substrate doctor blade coating method in an atmospheric environment, the hot substrate temperature is 150℃, the coating speed is 100 mm / min, the gap between the doctor blade and the substrate surface is 100 μm, and the thickness of the perovskite light absorption layer is 600 nm.

[0070] (4)Preparation of interface modification layer on the surface of perovskite thin film: hexanediamine methyl trimethoxysilane is dissolved in ethanol to prepare a 5 mmol / L hexanediamine methyl trimethoxysilane ethanol solution, then tetraethyl orthosilicate is added, and the molar ratio of hexanediamine methyl trimethoxysilane / tetraethyl orthosilicate is 1 / 10; after mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120°C for 30 minutes, and the thickness of the interface modification layer is 1 nm.

[0071] (5)Deposition of hole transport layer on the surface of the interface modification layer: the hole transport layer material (Spiro-OMeTAD solution) is spin-coated at a speed of 4000 rpm for 45 s to form a film, wherein the preparation method of the Spiro-OMeTAD solution is: 72.3 mg of Spiro-OMeTAD is added to 1 mL of chlorobenzene, stirred until clear, then 28.8 μL of TBP and 17.5 μL of Li-TFSI solution are added and stirred for 1 min, and the thickness of the hole transport layer is 150 nm.

[0072] (6)Finally, the thermal evaporation technology is used, when the vacuum degree reaches 2.0 x 10 -3 Pa, the film plating starts, wherein the rate during the deposition stability is 0.15 nm / s, and the deposition is stopped immediately after the display shows 80 nm, and the 80 nm gold electrode is obtained by evaporation. Finally, a perovskite solar cell is obtained.

[0073] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell is measured to be 18.6%, and the photoelectric conversion efficiency is tested to be 18.1% after being placed for 90 days under a humidity of 30%.

[0074] Example 3

[0075] A perovskite solar cell is prepared by the following steps:

[0076] (1) Cleaning of transparent conductive glass: the transparent conductive glass is sequentially cleaned with a mixed solution of deionized water and glass cleaner, deionized water, ethanol, and isopropanol by ultrasonic cleaning for 15 min, and then treated with ultraviolet ozone for 15 min to obtain clean FTO transparent conductive glass, and the conductive film thickness of the FTO transparent conductive glass is 300 nm.

[0077] (2) Preparation of an electron transport layer on a transparent conductive electrode: 500 mg of a tin oxide stock solution (15 wt%) was weighed out using deionized water as a solvent, and 2.5 mL of deionized water was added and shaken gently; a tin oxide nanocrystal thin film was prepared by spin coating at a rotation speed of 4000 rpm for 30 s, and finally annealed at 150°C for 30 min, and the thickness of the electron transport layer was 30 nm.

[0078] (3) Ultraviolet ozone treatment of the electron transport layer for 15 min, deposition of a perovskite precursor on the electron transport layer by doctor blade coating, and then crystallization into a film by annealing (perovskite light absorption layer): 276.6 mg of PbI2was dissolved in 200 μL of DMSO; 190.8 mg of MAI was dissolved in 300 μL of GBL; heating at 75°C for 1 h, and after MAI was completely dissolved, the two solutions were mixed; continued heating at 60°C for 3 h and magnetic stirring until complete dissolution; preparation of a perovskite thin film by hot substrate doctor blade coating in an atmospheric environment, with a hot substrate temperature of 150°C, a doctor blade coating speed of 100 mm / min, a gap between the doctor blade and the substrate surface of 100 μm, a spin coating rotation speed of 4000 rpm, a spin coating time of 45 s, an annealing temperature of 130°C, and an annealing time of 15 min, and the thickness of the perovskite light absorption layer was 600 nm.

[0079] (4) Preparation of an interface modification layer on the surface of the perovskite thin film: (3-aminopropyl)diethoxymethylsilane was dissolved in ethanol to prepare a 50 mmol / L (3-aminopropyl)diethoxymethylsilane ethanol solution, and then aluminum isopropoxide was added, with a (3-aminopropyl)diethoxymethylsilane / aluminum isopropoxide molar ratio of 1 / 2; after mixing, a film was formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment was performed at a temperature of 120°C for 30 min, and the thickness of the interface modification layer was 5 nm.

[0080] (5) Deposition of a hole transport layer on the surface of the interface modification layer: a hole transport layer material (Spiro-OMeTAD solution) was spin coated at a rotation speed of 4000 rpm to form a film, wherein the Spiro-OMeTAD solution was prepared as follows: 72.3 mg of Spiro-OMeTAD was added to 1 mL of chlorobenzene, stirred until clear, and then 28.8 μL of TBP and 17.5 μL of Li-TFSI solution were added and stirred for 1 min, and the thickness of the hole transport layer was 80 nm.

[0081] (6) Finally, a gold electrode was prepared by thermal evaporation technology when the vacuum degree reached 2.0 x 10 -3 Pa, the film plating began, the deposition rate was 0.15 nm / s when it was stable, and the deposition was stopped immediately after the display reading reached 200 nm. A 200 nm gold electrode was obtained by evaporation. Finally, a perovskite solar cell was obtained.

[0082] The light source is a solar simulator (standard light source) in a room temperature environment, and the light intensity is 100 mW / cm 2 The light conversion efficiency of the perovskite solar cell is 19.7%, and the tested photoelectric conversion efficiency is 17.7% after being placed for 90 days under the condition of 30% humidity.

[0083] Example 4

[0084] A perovskite solar cell is prepared by the following steps:

[0085] (1) Clean the transparent conductive glass: ultrasonically clean the transparent conductive glass with a mixed solution of deionized water and glass cleaner, deionized water, ethanol and isopropanol in sequence, the ultrasonic time is 15 min, and ultraviolet ozone treatment is performed for 15 min to obtain clean FTO transparent conductive glass.

[0086] (2) Prepare an electron transport layer on the FTO transparent conductive glass by a spin coating process: weigh 500 mg of tin oxide original solution (15 wt%) and add 2.5 mL of deionized water, and shake gently; prepare a tin oxide nanocrystalline thin film by spin coating at a speed of 4000 rpm for 30 s, and finally anneal at 150℃ for 30 min.

[0087] (3) Ultraviolet ozone treat the electron transport layer for 20 min, deposit a perovskite precursor on the electron transport layer by a doctor blade coating process, and then crystallize into a film by annealing (perovskite light absorption layer): dissolve 276.6 mg of PbI2 in 200 μL of DMSO; dissolve 190.8 mg of MAI in 300 μL of GBL; heat at 75℃ for 1 hour, and after MAI is completely dissolved, mix the two solutions; continue to heat at 60℃ for 3 hours and magnetically stir until completely dissolved; prepare a perovskite thin film by a hot substrate doctor blade coating method in an atmospheric environment, the hot substrate temperature is 150℃, the coating speed is 100 mm / min, and the gap between the doctor blade and the substrate surface is 100 μm.

[0088] (4) Prepare an interface modification layer on the surface of the perovskite thin film: dissolve N-aminoethyl-3-aminopropyl methyl dimethoxy silane in ethanol to prepare a 20 mmol / L N-aminoethyl-3-aminopropyl methyl dimethoxy silane ethanol solution, then add butyl titanate, and the molar ratio of N-aminoethyl-3-aminopropyl methyl dimethoxy silane to butyl titanate is 1 / 5; after mixing uniformly, film formation is performed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120℃ for 30 min.

[0089] (5) Depositing a hole transport layer on the surface of the interface modification layer: The hole transport layer material (Spiro-OMeTAD solution) was spin-coated at a rotation speed of 4000 rpm for 45 s to form a film, wherein the preparation method of the Spiro-OMeTAD solution was as follows: 72.3 mg of Spiro-OMeTAD was added into 1 mL of chlorobenzene, stirred until clear, and then 28.8 μL of TBP and 17.5 μL of Li-TFSI solution were added and stirred for 1 min.

[0090] (6) Finally, a thermal evaporation technique was used, and when the vacuum degree reached 2.0 x 10 -3 Pa, the film coating started, wherein the deposition rate was 0.15 nm / s when stable, and the deposition was stopped immediately after the display reading reached 140 nm. A 140 nm gold electrode was obtained by evaporation. Finally, a perovskite solar cell was obtained.

[0091] The thicknesses of the FTO transparent conductive glass, the electron transport layer, the perovskite light absorption layer, the interface modification layer, the hole transport layer, and the gold electrode were the same as in Example 1.

[0092] In a room temperature environment, the light source was a solar simulator (standard light source), and the light intensity was 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell was measured to be 20.7%, and the tested photoelectric conversion efficiency was 16.8% after being placed in a humidity of 30% for 90 days.

[0093] Example 5

[0094] A perovskite solar cell was prepared by the following steps:

[0095] (1) Cleaning the transparent conductive glass: The transparent conductive glass was sequentially ultrasonically cleaned with a mixed solution of deionized water and glass cleaner, deionized water, ethanol, and isopropanol, and ultrasonically cleaned for 15 min, and then treated with ultraviolet ozone for 15 min to obtain clean FTO transparent conductive glass.

[0096] (2) Preparing a hole transport layer on the transparent conductive electrode by a spin coating process: 500 mg of nickel oxide original solution (15 wt%) was weighed, 2.5 mL of deionized water was added, and the mixture was gently shaken, and a nickel oxide nanocrystalline thin film was prepared by spin coating at a rotation speed of 4000 rpm for 30 s, and finally annealed at 150°C for 30 min.

[0097] (3) Ultraviolet ozone treatment of the electron transport layer for 15 min, deposition of perovskite precursor on the electron transport layer by doctor blade coating process, and then crystallization into a film by annealing (perovskite light absorption layer): 276.6 mg of PbI2 is dissolved in 200 μL of DMSO; 190.8 mg of MAI is dissolved in 300 μL of GBL; heating at 75°C for 1 hour, after MAI is completely dissolved, mix the two solutions; continue to heat at 60°C for 3 hours and magnetically stir until completely dissolved; prepare the perovskite film by hot substrate doctor blade coating method in an atmospheric environment, the hot substrate temperature is 150°C, the coating speed is 100 mm / min, the gap between the doctor blade and the substrate surface is 100 μm, the spin coating speed is 4000 rpm, the spin coating time is 45 s, the annealing temperature is 130°C, and the annealing time is 15 min.

[0098] (4) Preparation of an interface modification layer on the surface of the perovskite film: N-phenyl-3-aminopropyltrimethoxysilane is dissolved in ethanol to prepare a 20 mmol / L N-phenyl-3-aminopropyltrimethoxysilane ethanol solution, then cerium isopropoxide is added, and the molar ratio of N-phenyl-3-aminopropyltrimethoxysilane / cerium isopropoxide is 1 / 5; after mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120°C for 30 min.

[0099] (5) Deposition of an electron transport layer on the surface of the modification layer: PCBM powder is dissolved in chloroform (CF) to obtain a PCBM solution with a concentration of 15 mg / mL, and a PCBM film is prepared by spin coating at a speed of 4000 rpm for 30 s.

[0100] (6) Finally, a gold electrode is prepared by thermal evaporation technology when the vacuum degree reaches 2.0 x 10 -3 Pa, the film plating starts, the deposition rate is 0.15 nm / s when it is stable, and the deposition is stopped immediately after the display reading reaches 140 nm. The perovskite solar cell is obtained.

[0101] The thicknesses of the FTO transparent conductive glass, the electron transport layer, the perovskite light absorption layer, the interface modification layer, the hole transport layer, and the gold electrode are the same as in Example 1.

[0102] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell is measured to be 18.7%, and the tested photoelectric conversion efficiency is 17.1% after being placed in a humidity of 30% for 90 days.

[0103] The comparison of the technical parameters of the interface modification layer of the perovskite solar cells obtained in Examples 1-5 and the light conversion efficiency of the cells is shown in Table 2:

[0104] Table 2 Statistics of efficiency and stability of perovskite solar cells of each example

[0105]

[0106]

[0107] Example 6

[0108] The same as example 1, except that:

[0109] (4) Preparing an interface modification layer on the surface of the perovskite thin film: dissolving diethylaminomethyl triethoxysilane in ethanol to prepare a 20 mmol / L diethylaminomethyl triethoxysilane ethanol solution, then adding aluminum isopropoxide, the molar ratio of diethylaminomethyl triethoxysilane / aluminum isopropoxide being 1 / 5, uniformly mixing, then forming a film by spin coating at a speed of 5000 rpm for 50 s, and then performing heat treatment at a temperature of 120°C for 30 minutes.

[0110] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell is measured to be 19.1%, and the photoelectric conversion efficiency is tested to be 18.2% after being placed in a humidity of 30% for 90 days.

[0111] Example 7

[0112] The same as example 1, except that:

[0113] (4) Preparing an interface modification layer on the surface of the perovskite thin film: dissolving diethylaminomethyl triethoxysilane in ethanol to prepare a 20 mmol / L diethylaminomethyl triethoxysilane ethanol solution, then adding aluminum isopropoxide, the molar ratio of diethylaminomethyl triethoxysilane / aluminum isopropoxide being 1 / 5, uniformly mixing, then forming a film by spin coating at a speed of 5000 rpm for 50 s, and then performing heat treatment at a temperature of 120°C for 30 minutes.

[0114] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell is measured to be 20.3%, and the photoelectric conversion efficiency is tested to be 18.4% after being placed in a humidity of 30% for 90 days.

[0115] Example 8

[0116] The same as example 1, except that:

[0117] (4) The interface modification layer is prepared on the surface of the perovskite film: diethylaminomethyl triethoxysilane is dissolved in ethanol to prepare a 20 mmol / L diethylaminomethyl triethoxysilane ethanol solution, then butyl titanate is added, the molar ratio of diethylaminomethyl triethoxysilane / butyl titanate is 1 / 5, after mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120°C for 30 minutes.

[0118] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell is measured to be 20.8%, and after being placed in a humidity of 30% for 90 days, the tested photoelectric conversion efficiency is 17.2%.

[0119] Example 9

[0120] The same as example 1, except that:

[0121] (4) The interface modification layer is prepared on the surface of the perovskite film: diethylaminomethyl triethoxysilane is dissolved in ethanol to prepare a 20 mmol / L diethylaminomethyl triethoxysilane ethanol solution, then butyl titanate is added, the molar ratio of diethylaminomethyl triethoxysilane / butyl titanate is 1 / 5, after mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120°C for 30 minutes.

[0122] In a room temperature environment, the light source is a solar simulator (standard light source), and the light intensity is 100 mW / cm 2 . The light conversion efficiency of the perovskite solar cell is measured to be 20.8%, and after being placed in a humidity of 30% for 90 days, the tested photoelectric conversion efficiency is 17.2%.

[0123] Example 10

[0124] The same as example 1, except that:

[0125] (4) The interface modification layer is prepared on the surface of the perovskite film: diethylaminomethyl triethoxysilane is dissolved in ethanol to prepare a 20 mmol / L diethylaminomethyl triethoxysilane ethanol solution, then butyl titanate is added, the molar ratio of diethylaminomethyl triethoxysilane / butyl titanate is 1 / 5, after mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120°C for 30 minutes.

[0126] The light source is a solar simulator (standard light source) at room temperature, and the light intensity is 100 mW / cm 2 The measured light conversion efficiency of the perovskite solar cell is 21.1%, and the tested photoelectric conversion efficiency is 19.6% after being placed in a humidity of 30% for 90 days.

[0127] Example 11

[0128] The same as example 1, except that:

[0129] (4) An interface modification layer is prepared on the surface of the perovskite thin film: (3-aminopropyl) diethoxymethylsilane is dissolved in ethanol to prepare a 20 mmol / L (3-aminopropyl) diethoxymethylsilane ethanol solution, then lanthanum isopropoxide is added, the molar ratio of (3-aminopropyl) diethoxymethylsilane / lanthanum isopropoxide is 1 / 5, after mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120°C for 30 minutes.

[0130] The light source is a solar simulator (standard light source) at room temperature, and the light intensity is 100 mW / cm 2 The measured light conversion efficiency of the perovskite solar cell is 20.2%, and the tested photoelectric conversion efficiency is 18.3% after being placed in a humidity of 30% for 90 days.

[0131] Example 12

[0132] The same as example 1, except that:

[0133] (4) An interface modification layer is prepared on the surface of the perovskite thin film: N-aminoethyl-3-aminopropyl methyldimethoxysilane is dissolved in ethanol to prepare a 20 mmol / L N-aminoethyl-3-aminopropyl methyldimethoxysilane ethanol solution, then lanthanum isopropoxide is added, the molar ratio of N-aminoethyl-3-aminopropyl methyldimethoxysilane / lanthanum isopropoxide is 1 / 5, after mixing uniformly, a film is formed by spin coating at a speed of 5000 rpm for 50 s, and then heat treatment is performed at a temperature of 120°C for 30 minutes.

[0134] The light source is a solar simulator (standard light source) at room temperature, and the light intensity is 100 mW / cm 2 The measured light conversion efficiency of the perovskite solar cell is 20.1%, and the tested photoelectric conversion efficiency is 17.6% after being placed in a humidity of 30% for 90 days.

[0135] Example 13

[0136] The same as example 1, except that:

[0137] (4) Preparing an interface modification layer on the surface of the perovskite thin film: N-phenyl-3-aminopropyl trimethoxysilane is dissolved in ethanol to prepare a 20 mmol / L N-phenyl-3-aminopropyl trimethoxysilane ethanol solution, then lanthanum isopropyl alcohol is added, the molar ratio of N-phenyl-3-aminopropyl trimethoxysilane / lanthanum isopropyl alcohol is 1 / 5, after mixing uniformly, a film is formed by spin coating, the spin coating speed is 5000 rpm, the time is 50 s, then heat treatment is performed, the heat treatment temperature is 120℃, and the heat treatment time is 30 minutes.

[0138] In a room temperature environment, the light source is a solar simulator (standard light source), the light intensity is 100 mW / cm 2 , the photovoltaic conversion efficiency of the perovskite solar cell is 19.5%, and the tested photovoltaic conversion efficiency is 17.9% after being placed in a humidity of 30% for 90 days.

[0139] The above is only the preferred embodiment of the present application, it should be noted that the above preferred embodiment should not be regarded as limiting the present application, the protection scope of the present application should be limited by the scope defined by the claims. For ordinary skilled in the art, without departing from the spirit and scope of the present application, a number of improvements and refinements can also be made, these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A perovskite solar cell, characterized by, The interface modification layer is prepared by the reaction of a silane coupling agent and a metal alkoxide, the silane coupling agent is an amino-containing silane coupling agent or an amine-containing silane coupling agent, the metal alkoxide is selected from one of aluminum isopropoxide, butyl titanate, cerium isopropoxide and lanthanum isopropoxide, the silane coupling agent is selected from one of diethylaminomethyl triethoxysilane, hexanediaminomethyl trimethoxysilane, (3-aminopropyl) diethoxymethyl silane, N-aminoethyl-3-aminopropyl methyl dimethoxysilane and N-phenyl-3-aminopropyl trimethoxysilane, the molar ratio of the silane coupling agent to the metal alkoxide is 1:2-1:10, and the molar concentration of the silane coupling agent in the alcohol solution of the silane coupling agent is 5-50 mmol / L.

2. The perovskite solar cell according to claim 1, characterized in that, The interface modification layer is prepared by the following steps: (1) dissolving the silane coupling agent in an ethanol or isopropanol solution to obtain an alcohol solution of the silane coupling agent, then adding the metal alkoxide and uniformly mixing to obtain an interface modification layer solution; (2) coating the modification layer solution on the surface of the perovskite light absorption layer, and then heat-treating the modification layer solution to obtain the interface modification layer.

3. The perovskite solar cell according to claim 2, characterized in that, The heat treatment temperature in step (2) is 100 o C-150 o C, and the heat treatment time is 25-35 minutes.

4. The perovskite solar cell according to claim 2, characterized in that, The coating of the modification layer solution in step (2) is performed by a spin coating method or an immersion method. 5.The perovskite solar cell of claim 1, wherein, The interface modification layer is prepared by the reaction of a silane coupling agent and a metal alkoxide, the silane coupling agent is an amino-containing silane coupling agent or an amine-containing silane coupling agent, the metal alkoxide is selected from one of aluminum isopropoxide, butyl titanate, cerium isopropoxide and lanthanum isopropoxide, the silane coupling agent is selected from one of diethylaminomethyl triethoxysilane, hexanediaminomethyl trimethoxysilane, (3-aminopropyl) diethoxymethyl silane, N-aminoethyl-3-aminopropyl methyl dimethoxysilane and N-phenyl-3-aminopropyl trimethoxysilane, the molar ratio of the silane coupling agent to the metal alkoxide is 1:2-1:10, and the molar concentration of the silane coupling agent in the alcohol solution of the silane coupling agent is 5-50 mmol / L. 6.The perovskite solar cell of claim 1, wherein, The interface modification layer is prepared by the following steps: (1) dissolving the silane coupling agent in an ethanol or isopropanol solution to obtain an alcohol solution of the silane coupling agent, then adding the metal alkoxide and uniformly mixing to obtain an interface modification layer solution; (2) coating the modification layer solution on the surface of the perovskite light absorption layer, and then heat-treating the modification layer solution to obtain the interface modification layer. The coating of the modification layer solution in step (2) is performed by a spin coating method or an immersion method.

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