Application of Methyl 2-[carbamoyl(methyl)amino]acetate Hydrochloride in Perovskite Solar Cells

Abstract

The present invention relates to the technical field of solar cell, and specifically discloses the application of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride in perovskite solar cells. By adding methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride and 2-(2-hydroxy-5-methylphenyl)benzotriazole to the perovskite thin film layer, the present invention effectively improves the ultraviolet resistance of the perovskite solar cell, reduces surface defects, enables the perovskite layer to have excellent phase stability, and also improves the photoelectric conversion efficiency. The perovskite solar cell prepared based on this perovskite passivation method has the advantages of high efficiency, stability and low cost. The development of such preparation technology provides a new device preparation strategy for the commercial application of perovskite solar cells.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and particularly to the application of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride in perovskite solar cells. Background Art

[0002] Perovskite solar cells have the advantages of low cost, simple preparation process and excellent performance, and are one of the most promising solar cells. So far, the stability and large-scale production of perovskite solar cells are two key problems that must be solved for the commercial application of perovskite solar cells. On the one hand, grain boundaries and interface defects of the perovskite absorber provide a pathway for ion migration, resulting in phase change and degradation of perovskite solar cells. On the other hand, environmental factors such as oxygen, moisture and incident light, especially ultraviolet radiation, can directly damage the perovskite layer, restricting the development of perovskite solar cells. Therefore, improving the stability of perovskite solar cells is a key problem that must be solved for its commercial application.

[0003] Currently, the stability of perovskite solar cells is mainly improved by doping a passivator in the perovskite thin film layer. However, doping other additives in the perovskite thin film layer will affect the film performance to a certain extent, which is not conducive to the transport of photo-generated carriers, reduces the charge transport ability, and thus reduces the efficiency of the device. Therefore, there is an urgent need for a method to passivate the perovskite thin film layer to improve the stability of perovskite solar cells and the photoelectric conversion efficiency of perovskite solar cells. Summary of the Invention

[0004] Aiming at the problem that doping other additives in the perovskite thin film layer will affect the film performance to a certain extent, which is not conducive to the transport of photo-generated carriers, reduces the charge transport ability, and thus reduces the photoelectric conversion efficiency of the device, the present invention provides the application of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride in perovskite solar cells.

[0005] To solve the above technical problems, the technical solution provided by the present invention is:

[0006] The application of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride as a passivator in perovskite solar cells.

[0007] The structure of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride in the present invention is shown as follows:

[0008]

[0009] For the existing technology, for the first time in the present invention, methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride is used as a passivating agent for a perovskite thin film layer. The NH3 in methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride + can be connected to I in PbI2 through hydrogen bonds - , effectively stabilizing I - and preventing the escape of I - ; the electrons containing carbonyl groups can coordinate with Pb 2+ , methylamine ions (MA + ), etc. to form Pb-O and MA-O bonds, reducing surface defects. Moreover, on the surface of the perovskite thin film layer modified with methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride, it will not affect the charge transport in the perovskite thin film bulk phase, and can improve the photoelectric conversion efficiency and stability of the solar cell assembled with the passivated perovskite thin film layer.

[0010] Preferably, the preparation method of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride includes the following steps:

[0011] Mix anhydrous creatine and methanol evenly to obtain a mixed solution; under an inert atmosphere, drop thionyl chloride into the mixed solution and react at 15°C to 30°C for 30 min to 60 min; then add ether to the reaction solution, cool down for crystallization, filter, and dry to obtain methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride.

[0012] Preferably, the molar ratio of methanol to anhydrous creatine is 4 - 5:1.

[0013] It should be noted that the above-mentioned methanol refers to anhydrous methanol.

[0014] Preferably, the molar ratio of anhydrous creatine to thionyl chloride is 1:1.1 - 1.3.

[0015] It should be noted that the temperature of the system needs to be controlled not to exceed 0°C during the dropping of thionyl chloride.

[0016] Preferably, the molar ratio of ether to anhydrous creatine is 1 - 2:1.

[0017] Preferably, the temperature for cooling crystallization is -5°C to 0°C, and the time for cooling crystallization is 1 h to 2 h.

[0018] Exemplarily, in the present invention, the above-mentioned inert atmosphere can be provided by common inert gases in the art, such as nitrogen, helium, etc.

[0019] The preferred preparation method of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride can improve the yield of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride.

[0020] The present invention also provides a passivated perovskite thin film layer, which comprises methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride and 2-(2-hydroxy-5-methylphenyl)benzotriazole.

[0021] In the present invention, methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride (CTY) is used as a passivating agent, and 2-(2-hydroxy-5-methylphenyl)benzotriazole (UVP) is used as an ultraviolet absorber. The ultraviolet rays are absorbed by the opening and closing of the chelate ring contained in UVP, thereby improving the stability of the perovskite thin film layer; and the N in the UVP molecule forms a coordination bond with Pb 2+ to passivate Pb 2+ ; in cooperation with CTY, further passivate I - 、Pb 2+ 、MA + and other ions, reduce the surface defects, thereby effectively improving the ultraviolet resistance of the perovskite thin film layer, making the perovskite layer have excellent phase stability, and at the same time improving the photoelectric conversion efficiency.

[0022] The present invention also provides a preparation method of the above passivated perovskite thin film layer, which comprises the following steps:

[0023] Step S1: Add PbI2 into a mixed solution of dimethyl sulfoxide and N,N-dimethylformamide, and mix evenly to obtain a perovskite precursor solution;

[0024] Take the perovskite precursor solution and add 2-(2-hydroxy-5-methylphenyl)benzotriazole, and mix evenly to obtain an additive solution;

[0025] Take the perovskite precursor solution and add methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride, and mix evenly to obtain a passivating agent solution;

[0026] Step S2: Dissolve formamidinium iodide, methylammonium chloride and methylammonium iodide in isopropanol to obtain an organic salt solution;

[0027] Step S3: Spin-coat the SnO2 solution on the pretreated ITO conductive glass and anneal to obtain an electron transport layer;

[0028] Step S4: Spin-coat the additive solution and the passivating agent solution on the electron transport layer in sequence, anneal, spin-coat the organic salt solution, and anneal to obtain the passivated perovskite thin film layer.

[0029] Preferably, in step S1, the concentration of PbI2 in the perovskite precursor solution is 1.4 mol / L to 1.5 mol / L.

[0030] Preferably, in step S1, the volume ratio of dimethyl sulfoxide to N,N-dimethylformamide is 8-10:1.

[0031] Preferably, in step S1, the concentration of 2-(2-hydroxy-5-methylphenyl) benzotriazole in the additive solution is 25 mM - 30 mM.

[0032] Preferably, in step S1, the mass concentration of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride in the passivator solution is 0.04% - 0.1%.

[0033] Preferably, in step S2, the mass ratio of formamidinium iodide, methylammonium chloride and iodomethylamine is 13 - 15:1 - 2:1.

[0034] Preferably, in step S2, the mass-to-volume ratio of formamidinium iodide to isopropanol is 90:1 - 2, where the unit of mass is milligram and the unit of volume is milliliter.

[0035] Exemplarily, the pretreatment process of ITO conductive glass is as follows: the ITO conductive glass is successively ultrasonically cleaned with deionized water and isopropanol, and after drying, it is treated with ultraviolet ozone for 20 min to obtain the pretreated ITO glass.

[0036] Preferably, in step S3, the SnO2 solution is a mixed solution of nanocrystalline tin dioxide solution and ammonia water with a volume ratio of 1:2.5 - 3.5, where the mass concentration of the nanocrystalline tin dioxide solution is 14% - 16%.

[0037] It should be noted that the above-mentioned nanocrystalline tin dioxide solution is a commercially available α-nanocrystalline tin dioxide solution with a mass concentration of about 15%. The above-mentioned ammonia water is industrial ammonia water with a mass concentration of 25% - 28%.

[0038] Exemplarily, in step S3, the rotation speed of spin-coating the SnO2 solution is 3800 r / min - 4200 r / min, the spin-coating time is 25 s - 35 s, and the spin-coating amount is 45 μL.

[0039] Preferably, in step S3, the annealing temperature is 115°C - 125°C, and the annealing time is 25 min - 35 min.

[0040] Preferably, in step S4, the rotation speed of spin-coating the additive solution is 1400 r / min - 1600 r / min, the spin-coating time is 25 s - 35 s, and the spin-coating amount is 50 μL.

[0041] Preferably, in step S4, the rotation speed of spin-coating the passivator solution is 1400 r / min - 1600 r / min, the spin-coating time is 25 s - 35 s, and the spin-coating amount is 40 μL.

[0042] Preferably, in step S4, after spin-coating the additive solution and the passivating agent solution, anneal at 65 °C to 75 °C for 1 min - 2 min.

[0043] Preferably, in step S4, the rotation speed of spin-coating the organic salt solution is 1800 r / min to 2200 r / min, the spin-coating time is 25 s to 35 s, and the spin-coating amount is 50 μL.

[0044] Preferably, in step S4, after spin-coating the organic salt solution, anneal at 145 °C to 155 °C for 14 min to 16 min.

[0045] The preparation method of the perovskite solar cell thin film layer provided by the present invention is simple, low in cost, does not require special equipment, is suitable for large-scale production applications, and is conducive to the commercial application of perovskite solar cells.

[0046] The present invention also provides a perovskite solar cell, including the above-mentioned passivated perovskite thin film layer or the passivated perovskite thin film layer prepared by the preparation method of the passivated perovskite thin film layer described in any one of the above.

[0047] It should be noted that the perovskite solar cell includes a conductive substrate, a composite electron transport layer, a perovskite thin film layer, a hole transport layer, and a back electrode layer.

[0048] Optionally, the above-mentioned conductive substrate is a flexible conductive substrate, which is prepared by preparing a transparent conductive layer on a flexible substrate and depositing an antireflection layer on the back. The flexible substrates applicable to the present invention include, but are not limited to, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone resin (PES), or polyimide (PI), etc. The transparent conductive layers applicable to the present invention include, but are not limited to, indium tin oxide (ITO), indium tungsten oxide, aluminum-doped zinc oxide (AZO), boron-doped zinc oxide, or fluorine-doped tin oxide (FTO), etc., and can be prepared by methods such as thermal evaporation, electron beam evaporation, and magnetron sputtering. The antireflection layers applicable to the present invention include, but are not limited to, MgF2, SiO2, etc., and the above antireflection layers can be deposited by methods such as thermal evaporation and magnetron sputtering.

[0049] The prepared flexible conductive substrate is ultrasonically cleaned with deionized water and isopropanol in sequence, the cleaning time is 30 minutes, and after cleaning, it can be used for the next step, such as preparing the perovskite thin film layer, after being treated with ultraviolet ozone for 30 min.

[0050] Optionally, the above-mentioned hole transport layer is prepared by the following method:

[0051] Spin-coat the Spiro-OMeTAD solution on the above-mentioned perovskite thin film layer, and anneal to form a hole transport layer.

[0052] The 1 mL Spiro-OMeTAD (2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene) solution contains 27 μL of tetra-tert-butylpiperidine and 17.3 μL of Li-TFSI acetonitrile solution, where the concentration of the Li-TFSI acetonitrile solution is 510 mg / mL.

[0053] Furthermore, the spin coating speed is 3800 r / min to 4200 r / min, and the spin coating time is 25 s to 35 s.

[0054] Optionally, the back electrode layer is a gold electrode or a silver electrode, and the back electrode layer is obtained on the hole transport layer by vacuum evaporation or vacuum sputtering.

[0055] Furthermore, the thickness of the back electrode layer is 80 nm. Detailed implementation manners

[0056] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0057] To better illustrate the present invention, further examples are given below through embodiments.

[0058] Embodiment 1

[0059] The preparation method of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride provided by the embodiment of the present invention includes the following steps:

[0060] Add 1 mol of anhydrous creatine and 4 mol of anhydrous methanol into a three-necked flask, mix evenly to obtain a mixed solution; under an inert atmosphere, drop 1.2 mol of thionyl chloride into the mixed solution, control the system temperature not to exceed 0 °C during the dropping process, and after the dropping is completed, raise the temperature to 25 °C and react for 30 min; then add 1.5 mol of ether to the reaction solution, cool down to 0 °C for crystallization for 1 h, filter, and dry to obtain methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride, with a yield of 80.1%.

[0061]

[0062] 1 H NMR (500 MHz, Chloroform-d, ppm) δ 6.90 (s, 1H), 5.52 (s, 2H), 4.12 (s, 2H), 3.73 (s, 3H), 3.04 (s, 3H).

[0063] Using other process conditions defined in the present invention to prepare methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride can achieve technical effects substantially equivalent to those of this example.

[0064] Example 2

[0065] An embodiment of the present invention provides a method for preparing a passivated perovskite thin film layer:

[0066] Step S1: Add PbI2 into a mixed solution of dimethyl sulfoxide and N,N-dimethylformamide with a volume ratio of 9:1, and mix evenly to obtain a perovskite precursor solution with a PbI2 concentration of 1.5 mol / L;

[0067] Take the perovskite precursor solution and add 2-(2-hydroxy-5-methylphenyl)benzotriazole, and mix evenly to obtain an additive solution with a concentration of 28 mM;

[0068] Take the perovskite precursor solution and add methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride, and mix evenly to obtain a passivator solution with a concentration of 0.06 wt%;

[0069] Step S2: Dissolve formamidinium iodide, methylammonium chloride, and methylammonium iodide with a ratio of 90:9:6.39 in isopropanol to obtain an organic salt solution, wherein the ratio of formamidinium iodide to isopropanol is 90 mg:1.5 mL;

[0070] Step S3: Mix 15 wt% nanocrystalline tin dioxide and 25%-28% industrial ammonia water by volume ratio of 1:3 evenly to obtain a tin dioxide solution;

[0071] Ultrasonically clean a 1.5 cm × 1.5 cm ITO conductive glass with deionized water and isopropanol for 30 min in sequence, dry it, and then treat it with ultraviolet ozone for 20 min to obtain a pretreated ITO glass;

[0072] Spin-coat the SnO2 solution on the pretreated ITO conductive glass at a rotation speed of 4000 r / min for 30 s with a spin-coating amount of 45 μL, and then anneal it at 120°C for 30 min to obtain an electron transport layer;

[0073] Step S4: Spin-coat the additive solution on the electron transport layer at a rotation speed of 1500 r / min for 30 s with a spin-coating amount of 50 μL; then spin-coat the passivator solution at 1500 r / min for 30 s with a spin-coating amount of 40 μL, then anneal it at 70°C for 1 min, and then spin-coat the organic salt solution at a rotation speed of 2000 r / min for 30 s with a spin-coating amount of 50 μL, and anneal it at 150°C for 15 min to obtain the passivated perovskite thin film layer.

[0074] Example 3

[0075] An embodiment of the present invention provides a method for preparing a passivated perovskite thin film layer:

[0076] Step S1: Add PbI2 into a mixed solution of dimethyl sulfoxide and N,N-dimethylformamide with a volume ratio of 8:1, and mix evenly to obtain a perovskite precursor solution with a PbI2 concentration of 1.4 mol / L;

[0077] Take the perovskite precursor solution and add 2-(2-hydroxy-5-methylphenyl) benzotriazole, and mix evenly to obtain an additive solution with a concentration of 30 mM;

[0078] Take the perovskite precursor solution and add methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride, and mix evenly to obtain a passivator solution with a concentration of 0.1 wt%;

[0079] Step S2: Dissolve formamidinium iodide, methylammonium chloride, and methylammonium iodide with a ratio of 13:1:1 in isopropanol to obtain an organic salt solution, wherein the ratio of formamidinium iodide to isopropanol is 90 mg:1 mL;

[0080] Step S3: Mix 15 wt% nanocrystalline tin dioxide and 25%-28% industrial ammonia water by volume ratio of 1:3.5 evenly to obtain a tin dioxide solution;

[0081] Ultrasonically clean a 1.5 cm × 1.5 cm ITO conductive glass with deionized water and isopropanol for 30 min in sequence, dry it, and then treat it with ultraviolet ozone for 20 min to obtain a pretreated ITO glass;

[0082] Spin-coat the SnO2 solution on the pretreated ITO conductive glass at a rotation speed of 3800 r / min for 35 s with a spin-coating amount of 45 μL, and then anneal it at 125°C for 25 min to obtain an electron transport layer;

[0083] Step S4: Spin-coat the additive solution on the electron transport layer at a rotation speed of 1600 r / min for 25 s with a spin-coating amount of 50 μL; then spin-coat the passivator solution at 1600 r / min for 25 s with a spin-coating amount of 40 μL, then anneal it at 75°C for 1 min, and then spin-coat the organic salt solution at a rotation speed of 1800 r / min for 35 s with a spin-coating amount of 50 μL, and anneal it at 145°C for 16 min to obtain the passivated perovskite thin film layer.

[0084] Example 4

[0085] An embodiment of the present invention provides a method for preparing a passivated perovskite thin film layer:

[0086] Step S1: Add PbI2 into a mixed solution of dimethyl sulfoxide and N,N-dimethylformamide with a volume ratio of 10:1, and mix evenly to obtain a perovskite precursor solution with a PbI2 concentration of 1.4 mol / L.

[0087] Take the perovskite precursor solution and add 2-(2-hydroxy-5-methylphenyl) benzotriazole, and mix evenly to obtain an additive solution with a concentration of 25 mM.

[0088] Take the perovskite precursor solution and add methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride, and mix evenly to obtain a passivator solution with a concentration of 0.04 wt%.

[0089] Step S2: Dissolve formamidinium iodide, methylammonium chloride, and iodomethylammonium in isopropanol at a ratio of 15:2:1 to obtain an organic salt solution, where the ratio of formamidinium iodide to isopropanol is 90 mg:2 mL.

[0090] Step S3: Mix nanocrystalline tin dioxide with a concentration of 15 wt% and industrial ammonia water with a mass concentration of 25%-28% evenly at a volume ratio of 1:2.5 to obtain a tin dioxide solution.

[0091] Ultrasonically clean a 1.5 cm × 1.5 cm ITO conductive glass with deionized water and isopropanol for 30 min in sequence, dry it, and then treat it with ultraviolet ozone for 20 min to obtain a pretreated ITO glass.

[0092] Spin-coat the SnO2 solution on the pretreated ITO conductive glass at a rotation speed of 4200 r / min for 25 s with a spin-coating amount of 45 μL, and then anneal it at 115 °C for 35 min to obtain an electron transport layer.

[0093] Step S4: Spin-coat the additive solution on the electron transport layer at a rotation speed of 1400 r / min for 35 s with a spin-coating amount of 50 μL; then spin-coat the passivator solution at 1400 r / min for 35 s with a spin-coating amount of 40 μL, then anneal it at 65 °C for 2 min, and then spin-coat the organic salt solution at a rotation speed of 2200 r / min for 25 s with a spin-coating amount of 50 μL, and anneal it at 155 °C for 14 min to obtain the passivated perovskite thin film layer.

[0094] To better illustrate the characteristics of the composite electron transport layer provided by the embodiments of the present invention, perovskite solar cells will be prepared from the perovskite thin film layers prepared in Examples 2-4, and then performance testing will be carried out.

[0095] The preparation method of the above perovskite solar cell includes the following steps:

[0096] At room temperature, a layer of indium tin oxide (ITO) transparent conductive layer was prepared on a polyethylene terephthalate (PET) flexible substrate by magnetron sputtering, and an MgF2 antireflection layer was deposited on the back to obtain a flexible conductive substrate. Then, the above flexible conductive substrate was ultrasonically cleaned with deionized water and isopropyl alcohol for 30 minutes respectively, and then treated with ultraviolet ozone for 30 minutes.

[0097] According to the steps of Examples 2 to 4 respectively, a passivated perovskite thin film layer was prepared on the above flexible conductive substrate.

[0098] A hole transport layer was prepared by spin-coating Spiro-OMeTAD solution uniformly on the above passivated perovskite thin film layer. Among them, 27 μL of tetra-tert-butylpiperidine and 17.3 μL of Li-TFSI acetonitrile solution were contained in 1 mL of Spiro-OMeTAD solution, and the concentration of the Li-TFSI acetonitrile solution was 510 mg / mL.

[0099] An Au electrode was vacuum-evaporated on the above hole transport layer, and the thickness of the back electrode layer was 80 nm to obtain a perovskite solar cell.

[0100] The above-prepared perovskite solar cell was placed under a solar simulator (Abet Sun 3000) and irradiated with standard light at 100 mW / cm 2 for photovoltaic conversion efficiency testing. The measurement bias voltage was 1.25 V - 0.1 V, and the effective area of the cell was 0.06 cm 2 . The test results are shown in Table 1.

[0101] Table 1

[0102]

[0103] In summary, by adding methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride and 2-(2-hydroxy-5-methylphenyl)benzotriazole to the perovskite thin film layer, the present invention effectively improves the ultraviolet resistance of the perovskite solar cell, reduces surface defects, enables the perovskite layer to have excellent phase stability, and at the same time improves the photoelectric conversion efficiency. The perovskite solar cell prepared based on this passivated perovskite method has the advantages of high efficiency, stability and low cost. The development of such preparation technology provides a new device preparation strategy for the commercial application of perovskite solar cells.

[0104] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements or improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Application of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride as a perovskite film passivator in perovskite solar cells.

2. The application according to claim 1, characterized in that, The preparation method of the methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride comprises the following steps: Mix anhydrous creatine and methanol uniformly to obtain a mixed solution; under an inert atmosphere, drop thionyl chloride into the mixed solution, and react at 15°C to 30°C for 30 min to 60 min; then add diethyl ether to the reaction solution, cool down for crystallization, filter, and dry to obtain methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride.

3. The application according to claim 2, characterized in that, The molar ratio of the methanol to the anhydrous creatine is 4 - 5:1; and / or The molar ratio of the anhydrous creatine to the thionyl chloride is 1:1.1 - 1.3; and / or The molar ratio of the diethyl ether to the anhydrous creatine is 1 - 2:

1.

4. The application according to claim 2, characterized in that The temperature for cooling down and crystallizing is -5°C to 0°C, and the time for cooling down and crystallizing is 1 h to 2 h.

5. A passivated perovskite thin film layer, characterized in that, It includes methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride and 2-(2-hydroxy-5-methylphenyl)benzotriazole.

6. The preparation method of the passivated perovskite thin film layer according to claim 5, characterized in that, It comprises the following steps: Step S1, add PbI2 into a mixed solution of dimethyl sulfoxide and N,N-dimethylformamide, mix uniformly to obtain a perovskite precursor solution; Take the perovskite precursor solution, add 2-(2-hydroxy-5-methylphenyl)benzotriazole, and mix uniformly to obtain an additive solution; Take the perovskite precursor solution, add methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride, and mix uniformly to obtain a passivator solution; Step S2, dissolve formamidinium iodide, methylammonium chloride, and methylammonium iodide in isopropanol to obtain an organic salt solution; Step S3, spin-coat a SnO2 solution on a pretreated ITO conductive glass, and anneal to obtain an electron transport layer; Step S4, sequentially spin-coat the additive solution and the passivator solution on the electron transport layer, anneal, spin-coat the organic salt solution, and anneal to obtain the passivated perovskite thin film layer.

7. The preparation method of the passivated perovskite thin film layer according to claim 6, characterized in that, In step S1, the concentration of PbI2 in the perovskite precursor solution is 1.4 mol / L to 1.5 mol / L; and / or In step S1, the volume ratio of the dimethyl sulfoxide to the N,N-dimethylformamide is 8 - 10:1; and / or In step S1, the concentration of 2-(2-hydroxy-5-methylphenyl)benzotriazole in the additive solution is 25 mM to 30 mM; and / or In step S1, the mass concentration of methyl 2-[carbamoyl(methyl)amino]acetate hydrochloride in the passivator solution is 0.04% to 0.1%.

8. The method for preparing the passivated perovskite thin film layer according to claim 6, characterized in that, In step S2, the mass ratio of the formamidinium iodide, methylammonium chloride, and methylammonium iodide is 13 - 15:1 - 2:1; and / or In step S2, the mass-volume ratio of the formamidinium iodide to the isopropanol is 90:1 - 2, where the unit of mass is milligram and the unit of volume is milliliter.

9. The preparation method of the passivated perovskite thin film layer according to claim 6, wherein, In step S3, the SnO2 solution is a mixed solution of a nanocrystalline tin dioxide solution and ammonia water with a volume ratio of 1:2.5 - 3.5, where the mass concentration of the nanocrystalline tin dioxide solution is 14% to 16%; and / or In step S3, the annealing temperature is 115°C to 125°C, and the annealing time is 25 min to 35 min.

10. A perovskite solar cell, characterized in that: It includes the passivated perovskite thin film layer described in claim 5 or the passivated perovskite thin film layer prepared by the preparation method of the passivated perovskite thin film layer described in any one of claims 6 to 9.

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