A perovskite solar cell doped with methyl 3-amino-2-thiophenecarboxylate and a preparation method thereof

Abstract

The application provides a perovskite solar cell doped with 3-amino-2-thiophene methyl formate and a preparation method thereof. The amino group, the ester group, the nitrogen atom, the oxygen atom and the sulfur atom on the thiophene in the 3-amino-2-thiophene methyl formate can be coordinated with cation and anion vacancy defects in the perovskite to synergistically passivate defects on the surface and the grain boundary of the perovskite crystal, reduce trap state density, inhibit non-radiative recombination of the perovskite film and prolong carrier lifetime. The introduction of the dopant can promote the growth of a high-quality perovskite film, obtain a perovskite film with better crystallinity and fewer grain boundaries, promote light absorption and carrier transport and improve the photoelectric conversion efficiency of the doped perovskite solar cell. The 3-amino-2-thiophene methyl formate can also improve the hydrophobicity of the perovskite film and the aging resistance of the perovskite film under the conditions of light, heating, water vapor and oxygen, and improve the environmental stability, light stability and thermal stability of the doped perovskite solar cell.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of perovskite solar cells, and in particular to a method for preparing a high-efficiency and stable inverted structure perovskite solar cell by doping a perovskite layer with an organic small molecule material. BACKGROUND

[0002] As a new generation of solar cells, perovskite solar cells have developed rapidly in the past decade, with the photoelectric conversion efficiency of the cells rapidly increasing from 3.8% to 25.7%. Perovskite materials have many advantages such as long carrier lifetime, double carrier transport, wide light absorption range, and solution processability. Their excellent performance and great potential in the photovoltaic field have made them a hot research topic in the photovoltaic field. However, due to the ionic nature of perovskite materials, a large number of various defects exist in the perovskite thin film during solution preparation and growth, existing in the crystal surface and grain boundaries. The existence of these defects will become the recombination center of carriers, thereby causing the efficiency of perovskite solar cells to decrease and the hysteresis phenomenon to be serious. In addition, as the starting site for the degradation of perovskite, defects make perovskite prone to decomposition under the conditions of light, heat, water vapor, and oxygen, thereby affecting the long-term stability. This has become a problem hindering the commercialization of perovskite solar cells.

[0003] Studies have shown that reducing the defects present in the perovskite structure and obtaining a perovskite thin film with high crystalline quality are the key to improving the photovoltaic performance and stability of perovskite solar cells. Among the various strategies that have been developed, additive engineering is considered to be a simple and effective method to improve device performance. Therefore, it is of great significance to improve the photovoltaic performance and stability of perovskite solar cells by exploring new and efficient perovskite additives to be introduced into the perovskite layer.

[0004] In view of this, we have invented a perovskite solar cell doped with 3-amino-2-thiophene formic acid methyl ester. SUMMARY

[0005] In order to overcome the above-mentioned deficiencies existing in the prior art, the purpose of the present application is to disclose a perovskite solar cell doped with 3-amino-2-thiophene formic acid methyl ester and a preparation method thereof, to provide a perovskite solar cell doped with a multifunctional group organic small molecule additive, specifically by introducing a 3-amino-2-thiophene formic acid methyl ester additive into the perovskite light-absorbing layer to prepare an inverted structure perovskite solar cell with high photoelectric conversion efficiency and high stability.

[0006] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0007] A perovskite solar cell doped with 3-amino-2-thiophene methylate, characterized in that, from bottom to top, it comprises an anode substrate, a hole transport layer, an interface modification layer, a perovskite light absorption layer, an electron transport layer, a hole blocking layer and a cathode electrode;

[0008] The perovskite light absorption layer is a 3-amino-2-thiophene methylate doped perovskite layer, and the perovskite of the perovskite light absorption layer is composed of at least one ion from among Cs + , MA + and FA + , and has a general formula of FA 1-x- y MA y Cs x PbI 3-z Br z (0≤x<1, 0≤y≤1, x+y≤1, 0≤z<3).

[0009] The perovskite light absorption layer is prepared by an anti-solvent method, and the anti-solvent used is a chlorobenzene solution containing 3-amino-2-thiophene methylate.

[0010] As a preferred scheme of the above scheme, the perovskite of the perovskite light absorption layer is FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 ; the anode substrate is ITO glass or FTO glass, the hole transport layer is PTAA, the interface modification layer is PFN-Br, the electron transport layer is C 60 , the hole blocking layer is BCP, and the cathode top electrode is Ag or Cu, and the thickness of the top electrode is 60-100 nm.

[0011] As a preferred scheme of the above scheme, the concentration of the 3-amino-2-thiophene methylate in the anti-solvent solution is 2-5 mg / mL.

[0012] As a preferred scheme of the above scheme, the preparation method of the perovskite solar cell doped with 3-amino-2-thiophene methylate comprises the following steps:

[0013] (1) cleaning the anode substrate, then performing surface treatment on the anode substrate to obtain a surface-treated anode surface;

[0014] (2) sequentially spin-coating a hole transport layer and an interface modification layer on the surface-treated anode surface of step (1);

[0015] (3) adding methyl 3-amino-2-thiophenecarboxylate into the solvent to dissolve to obtain an anti-solvent solution;

[0016] (4) spin-coating a perovskite light-absorbing layer on the surface of the interface modification layer in step (2);

[0017] (5) sequentially evaporating an electron transport layer, a hole blocking layer and a cathode electrode on the surface of the perovskite light-absorbing layer in step (4) to obtain the perovskite solar cell doped with methyl 3-amino-2-thiophenecarboxylate.

[0018] On the basis of the above scheme and as a preferred scheme of the above scheme, the surface treatment in step (1) comprises: sequentially ultrasonic cleaning the ITO glass with ITO glass cleaning agent, deionized water, acetone and isopropanol for 20-30 minutes, then blowing the anode substrate dry with a nitrogen stream, and finally performing plasma surface treatment on the surface of the cleaned and dried anode substrate for 5-10 minutes by using a Plasma cleaning machine.

[0019] On the basis of the above scheme and as a preferred scheme of the above scheme, the process for preparing the hole transport layer in step (2) is: spin-coating a PTAA toluene solution on the surface-treated anode substrate, and then performing annealing treatment to obtain the hole transport layer; wherein the spin-coating speed is 5000-6000 rpm, and the spin-coating time is 30-40 seconds; the annealing temperature is 90-110℃, and the annealing time is 5-10 minutes; and the concentration of the PTAA toluene solution is 1.5-2.5 mg / mL.

[0020] On the basis of the above scheme and as a preferred scheme of the above scheme, the process for preparing the interface modification layer in step (2) is: spin-coating a PFN-Br DMF solution on the surface of the PTAA to obtain the interface modification layer; wherein the spin-coating speed is 5000-6000 rpm, and the spin-coating time is 10-30 seconds; and the solubility of the PFN-Br DMF solution is 0.2-1.0 mg / mL.

[0021] On the basis of the above scheme and as a preferred scheme of the above scheme, the preparation of the perovskite light-absorbing layer in step (4) comprises:

[0022] I. Preparation of perovskite precursor mixed solution

[0023] FAI, CsI, PbI2 and PbBr2 are added into a mixed solvent of DMF and DMSO respectively, and stirred uniformly to form a perovskite precursor mixed solution;

[0024] II. Spin-coating deposition of perovskite

[0025] The perovskite precursor mixed solution is deposited on the surface of the interface modification layer through a two-stage spin coating process, and 100-300 uL of prepared anti-solvent solution is added dropwise at 10-20 seconds in the second stage, and the perovskite light-absorbing layer is obtained after annealing treatment, and the annealing treatment temperature is 90-110 DEG C, and the time is 10-30 minutes.

[0026] The two-stage spin coating process includes: (1) 500-1500 rpm for 5-10 seconds; (2) 5000-6000 rpm for 25-40 seconds.

[0027] On the basis of the above scheme and as a preferred scheme of the above scheme, the volume ratio of DMF to DMSO in the perovskite precursor mixed solution is 3:1-5:1; in the perovskite precursor mixed solution, FAI, CsI, PbI2 and PbBr2 are mixed according to the stoichiometric ratio of FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 The concentration of the halide of lead in the perovskite precursor solution is 1-1.5 M.

[0028] On the basis of the above scheme and as a preferred scheme of the above scheme, the operation steps of step (5) include: first, evaporating an electron transport layer on the surface of the perovskite light-absorbing layer, with a thickness of 10-30 nm; then evaporating a hole blocking layer on the electron transport layer, with a thickness of 5-10 nm; finally, evaporating an Ag or Cu cathode electrode, with a thickness of 60-100 nm.

[0029] Compared with the prior art, the technical scheme of the present application has the following beneficial effects:

[0030] (1) The preparation method of the 3-amino-2-thiophene methyl carboxylate doped inverted perovskite solar cell provided by the present application uses the chlorobenzene solution of 3-amino-2-thiophene methyl carboxylate as an anti-solvent to prepare a perovskite film, and a perovskite film with better crystallinity and fewer grain boundaries is prepared, and the surface morphology and crystallinity of the perovskite light-absorbing layer can be adjusted by adjusting the addition amount of 3-amino-2-thiophene methyl carboxylate, thereby affecting the light absorption performance, the transport and collection efficiency of photo-generated carriers, and the stability of the perovskite film, thereby providing a new method for preparing a perovskite solar cell with high efficiency and high stability.

[0031] (2) The preparation method of the 3-amino-2-thiophene methyl carboxylate doped inverted perovskite solar cell provided by the application is to use the chlorobenzene solution of 3-amino-2-thiophene methyl carboxylate as an anti-solvent to prepare a perovskite film. The additive contains three functional groups of amino, ester and thiophene, can coordinate and interact with defects in the perovskite, cooperatively passivate defects in the perovskite and reduce trap state density, so that non-radiative recombination in the perovskite is inhibited, the carrier lifetime is prolonged, and the degradation and decomposition of the perovskite are inhibited. Finally, the photoelectric conversion efficiency and stability of the perovskite solar cell are obviously improved.

[0032] (3) Compared with the perovskite solar cell without adding 3-amino-2-thiophene methyl carboxylate, the short-circuit current density, open-circuit voltage and fill factor of the perovskite solar cell doped with 3-amino-2-thiophene methyl carboxylate are obviously improved, and the environmental stability, light stability and thermal stability of the device are also significantly improved.

[0033] It should be understood that all combinations of the aforementioned concepts and additional concepts described below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter.

[0034] The foregoing and other aspects, embodiments and features of the present teachings can be better understood from the following description of the present teachings, taken in conjunction with the accompanying drawings. Other aspects, embodiments and features of the present teachings will become apparent from the following description of the present teachings, taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0035] The structures, proportions, sizes, etc. shown in the present disclosure are merely intended to facilitate the understanding of the present disclosure disclosed herein, to be understood and read by those skilled in the art, and are not intended to limit the defined conditions under which the present disclosure can be implemented. Any modification of structure, change of proportion relationship or adjustment of size, which does not affect the effects and purposes that can be achieved by the present disclosure, shall still fall within the scope of the technology disclosed by the present disclosure.

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed in the embodiments or prior art description will be briefly introduced below. The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments combined with the following drawings, in which:

[0037] Figure 1 Structure diagram of the doped perovskite solar cell of the present application;

[0038] Figure 2A flow chart of a preparation method of a doped perovskite solar cell;

[0039] Figure 3 A current density-voltage graph of the perovskite solar cells of Comparative Example and Examples 1-3;

[0040] Figure 4 A comparison graph of the environmental stability of the perovskite solar cells of Example 1 and Comparative Example;

[0041] Figure 5 A comparison graph of the thermal stability of the perovskite solar cells of Example 1 and Comparative Example.

[0042] In the figure, 1, anode substrate; 2, hole transport layer; 3, interface modification layer; 4, perovskite light absorption layer; 5, electron transport layer; 6, hole blocking layer; 7, cathode electrode. DETAILED DESCRIPTION

[0043] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the present application will be described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the described embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without any creative effort belong to the scope of protection of the present application. Unless otherwise defined, the technical terms or scientific terms used herein should have the usual meanings understood by those of ordinary skill in the art to which the present application belongs.

[0044] The terms "first", "second", and similar terms used in the patent application specification and claims of the present application do not represent any order, number or importance, but are only used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms "a", "an" or "the" and the like do not represent a quantity limitation, but represent the existence of at least one. The terms "include" or "contain" and the like mean that the elements or objects appearing before "include" or "contain" cover the features, whole, steps, operations, elements and / or components listed after "include" or "contain", and do not exclude the existence or addition of one or more other features, whole, steps, operations, elements, components and / or sets thereof. "Up", "down", "left", "right" and the like are only used to represent relative positional relationships, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0045] Example 1

[0046] The structure of the perovskite solar cell modified by doping in this embodiment 1 is as follows:

[0047] ITO / PTAA / PFN-Br / FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 : 3-amino-2-thiophene methylate / C 60 / BCP / Ag.

[0048] The preparation process of the perovskite solar cell doped with 3-amino-2-thiophene methylate in the embodiment is as follows:

[0049] Step 1, sequentially ultrasonic cleaning ITO glass with ITO glass cleaning agent, deionized water, acetone, isopropanol for 30 minutes; then blowing dry the anode substrate with nitrogen;

[0050] Step 2, plasma surface treatment is performed on the surface of the cleaned and dried anode substrate (ITO) for 10 minutes, which uses the plasma generated by the Plasma cleaning machine to clean the ITO surface of residual organic matter, etc., and can also improve the work function of the ITO surface;

[0051] Step 3, spin coating 2mg / mL PTAA toluene solution on the ITO surface treated in step 2, the spin coating speed is 6000rpm, and the spin coating time is 30 seconds. Annealing treatment is performed at 100°C for 10 minutes to form a hole transport layer.

[0052] Step 4, spin coating 0.5mg / mL PFN-Br DMF solution on the surface of the hole transport layer, the spin coating speed is 6000rpm, and the spin coating time is 20 seconds to obtain the interface modification layer.

[0053] Step 5, further, 3.5mg of 3-amino-2-thiophene methylate powder is dissolved in 1mL of chlorobenzene solvent, placed on a magnetic stirrer for stirring, and taken out after complete dissolution as an anti-solvent for standby.

[0054] Step 6, spin coating perovskite precursor mixed solution on the surface of the interface modification layer, the perovskite light absorbing layer is FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 , the specific preparation process is: dissolving FAI and CsI, PbI2 and PbBr2 in a mixed solvent of DMF and DMSO in a volume ratio of 4:1 according to the stoichiometric ratio of FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 , the concentration of lead halide in the perovskite precursor solution is 1.2M.

[0055] After fully stirring, the precursor mixture solution is deposited according to a two-stage spin coating process: first, run at 1000 rpm for 10 seconds, then at 6000 rpm for 30 seconds, at 15 seconds before the end of the second stage spin coating, drop 200 uL of the anti-solvent solution of 3-amino-2-thiophene carboxylic acid methyl ester on the rotating substrate, then anneal at 100°C for 20 minutes to form a perovskite light absorbing layer.

[0056] Step 7, evaporate an electron transport layer on the surface of the perovskite layer, with a thickness of 15 nm; then evaporate a hole blocking layer on the electron transport layer, with a thickness of 5 nm; finally, evaporate an Ag or Cu cathode top electrode, with a thickness of 80 nm.

[0057] After the above steps, a 3-amino-2-thiophene carboxylic acid methyl ester doped perovskite solar cell is obtained.

[0058] Example 2

[0059] The perovskite solar cell structure doped and modified in this example 2 is as follows:

[0060] ITO / PTAA / PFN-Br / FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 : 3-amino-2-thiophene carboxylic acid methyl ester / C 60 / BCP / Ag.

[0061] The preparation process of the above doped 3-amino-2-thiophene carboxylic acid methyl ester perovskite solar cell is as follows:

[0062] Step 1, sequentially clean the ITO glass with ITO glass cleaner, deionized water, acetone, and isopropanol for 30 minutes each; then dry the anode substrate with nitrogen;

[0063] Step 2, perform 10 minutes of plasma surface treatment on the surface of the cleaned and dried anode substrate (ITO), which utilizes the plasma generated by the Plasma cleaner to clean the ITO surface of residual organic matter, etc., while also increasing the work function of the ITO surface;

[0064] Step 3, spin coat a 2 mg / mL PTAA solution in toluene on the ITO surface treated in Step 2, with a spin speed of 6000 rpm and a spin coating time of 30 seconds. Anneal at 100°C for 10 minutes to form a hole transport layer.

[0065] Step 4, spin coat a 0.5 mg / mL PFN-Br solution in DMF on the surface of the hole transport layer, with a spin speed of 6000 rpm and a spin coating time of 20 seconds, to obtain the interface modification layer.

[0066] Step 5, further, 2 mg of 3-amino-2-thiophenecarboxylic acid methyl ester powder was dissolved in 1 mL of chlorobenzene solvent, placed on a magnetic stirrer for stirring, and after complete dissolution, removed as an anti-solvent for standby.

[0067] Step 6, spin-coating a perovskite precursor mixed solution on the surface of the interface modification layer, the perovskite light-absorbing layer is FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 , the specific preparation process is: FAI and CsI, PbI2 and PbBr2 are mixed and dissolved in a mixed solvent of DMF and DMSO in a volume ratio of 4:1 according to the stoichiometric ratio of FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 , the concentration of lead halide in the perovskite precursor solution is 1.2M.

[0068] After sufficient stirring, the precursor mixed solution is deposited by a two-stage spin-coating process: first at 1000 rpm for 10 seconds, then at 6000 rpm for 30 seconds, 200 μL of anti-solvent solution containing 3-amino-2-thiophenecarboxylic acid methyl ester is dropped onto the rotating substrate 15 seconds before the end of the second stage of spin-coating, and then annealed at 100°C for 20 minutes to form a perovskite light-absorbing layer.

[0069] Step 7, an electron transport layer is sequentially evaporated on the surface of the above perovskite layer, with a thickness of 15 nm; then an electron transport layer is evaporated on the surface of the electron transport layer, with a thickness of 5 nm; finally, an Ag or Cu cathode top electrode is evaporated, with a thickness of 80 nm.

[0070] After the above steps, a 3-amino-2-thiophenecarboxylic acid methyl ester doped perovskite solar cell is obtained.

[0071] Example 3

[0072] The perovskite solar cell structure doped and modified in this example 3 is:

[0073] ITO / PTAA / PFN-Br / FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 : 3-amino-2-thiophenecarboxylic acid methyl ester / C 60 / BCP / Ag.

[0074] The preparation process of the above doped 3-amino-2-thiophenecarboxylic acid methyl ester perovskite solar cell is as follows:

[0075] Step 1, the ITO glass was cleaned with ITO glass cleaner, deionized water, acetone, isopropanol, respectively, and ultrasonic cleaning for 30 minutes; then the anode substrate was dried with nitrogen;

[0076] Step 2, the surface of the cleaned and dried anode substrate (ITO) was treated with plasma for 10 minutes. The ITO surface was cleaned of residual organic matter by using the plasma generated by the Plasma cleaner, and the work function of the ITO surface was also improved.

[0077] Step 3, a 2mg / mL solution of PTAA in toluene was spin-coated on the ITO surface treated in Step 2 at a speed of 6000rpm for 30 seconds. The hole transport layer was formed by annealing at 100°C for 10 minutes.

[0078] Step 4, a 0.5mg / mL solution of PFN-Br in DMF was spin-coated on the surface of the hole transport layer at a speed of 6000rpm for 20 seconds to obtain the interface modification layer.

[0079] Step 5, further, 5mg of 3-amino-2-thiophene carboxylate methyl powder was dissolved in 1mL of chlorobenzene solvent and placed on a magnetic stirrer for stirring. After complete dissolution, it was removed as an anti-solvent for standby.

[0080] Step 6, a perovskite precursor mixed solution was spin-coated on the surface of the interface modification layer. The perovskite light-absorbing layer was FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 . The specific preparation process was as follows: FAI and CsI, PbI2 and PbBr2 were mixed and dissolved in a mixed solvent of DMF and DMSO in a volume ratio of 4:1 according to the stoichiometric ratio of FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 , and the concentration of lead halide in the perovskite precursor solution was 1.2M.

[0081] After sufficient stirring, the precursor mixed solution was deposited by a two-stage spin-coating process: first at 1000rpm for 10 seconds, then at 6000rpm for 30 seconds. At 15 seconds before the end of the second stage of spin-coating, 200μL of anti-solvent solution containing 3-amino-2-thiophene carboxylate methyl was dropped onto the rotating substrate, and then annealed at 100°C for 20 minutes to form the perovskite light-absorbing layer.

[0082] Step 7, an electron transport layer with a thickness of 15 nm is evaporated on the surface of the perovskite layer; then a hole blocking layer with a thickness of 5 nm is evaporated on the electron transport layer; finally, an Ag or Cu cathode top electrode with a thickness of 80 nm is evaporated.

[0083] After the above steps, a methyl 3-amino-2-thiophenecarboxylate doped perovskite solar cell is obtained.

[0084] Comparative Example

[0085] Different from Example 1, no methyl 3-amino-2-thiophenecarboxylate is added in the chlorobenzene anti-solvent in Step 5, and a perovskite thin film and a perovskite solar cell without methyl 3-amino-2-thiophenecarboxylate doping are prepared.

[0086] Performance Test

[0087] The following Table 1 compares the parameters of the perovskite solar cells prepared in the comparative example and Examples 1-3, and the test is performed under a 100 milliwatt / square centimeter solar simulator.

[0088] Table 1 Comparison of parameters of perovskite solar cells

[0089]

[0090] As can be seen from Table 1, the open-circuit voltage (V oc ) of Example 1 is increased from 1.102 V to 1.135 V, the short-circuit current (J sc ) is increased from 22.52 mA / cm 2 to 23.57 mA / cm 2 , and the fill factor (FF) is increased from 79.28% to 80.39%. This shows that after the introduction of methyl 3-amino-2-thiophenecarboxylate, the carrier transport and collection efficiency of the perovskite solar cell are improved, and due to the synergistic passivation effect of the multifunctional groups of methyl 3-amino-2-thiophenecarboxylate, the defects at the perovskite surface and grain boundaries are effectively inhibited, the film quality is improved, the energy loss caused by non-radiative recombination is significantly reduced, and thus the photoelectric conversion efficiency is increased from 19.67% to 21.51%, an increase of 9.4%. At the same time, compared with the comparative example, the parameters of Examples 2 and 3 are improved to different degrees, but the effect is not as good as that of Example 1, so according to the experimental results, we determine that the additive concentration used in Example 1 is the best concentration.

[0091] Figure 3 The current density-voltage relationship curves of the perovskite solar cells prepared in the comparative example and Examples 1-3 are shown in Figure 3 It can be seen from the figure that the open-circuit voltage (V oc) is 1.102 V, short-circuit current density (J sc ) is 22.52 mA / cm 2 , and fill factor (FF) is 79.28%; the open-circuit voltage (V oc ) of the doped perovskite solar cell of Example 1 is 1.135 V, short-circuit current density (J sc ) is 23.57 mA / cm 2 , and fill factor (FF) is 80.39%. It can be seen that the short-circuit current density, open-circuit voltage and fill factor of the perovskite solar cell device doped with methyl 3-amino-2-thiophenecarboxylate are obviously improved, which indicates that the introduction of methyl 3-amino-2-thiophenecarboxylate can effectively improve the carrier transport and collection efficiency, promote light absorption, reduce the internal defect state density of perovskite and inhibit the energy loss caused by non-radiative recombination.

[0092] Figure 4 is a stability comparison chart of the perovskite solar cells prepared in Example 1 and the comparative example under the environmental condition of 40% relative humidity, and the photoelectric conversion efficiency in the chart is normalized. It can be directly seen from the chart that the photoelectric conversion efficiency of the doped perovskite solar cell in Example 1 can be maintained at more than 60% of the initial efficiency after 500 hours, but the photoelectric conversion efficiency of the undoped perovskite solar cell in the comparative example is only 40% of the initial efficiency, and the environmental stability of the perovskite solar cell is significantly improved by introducing methyl 3-amino-2-thiophenecarboxylate as an additive in the perovskite light-absorbing layer.

[0093] Figure 5 is a stability comparison chart of the doped perovskite solar cell prepared in Example 1 and the undoped perovskite solar cell prepared in the comparative example under the heat treatment condition of 80°C, and the photoelectric conversion efficiency in the chart is normalized. It can be directly seen from the chart that the photoelectric conversion efficiency of the doped perovskite solar cell in Example 1 can be maintained at 90% of the initial efficiency after 800 hours, but the photoelectric conversion efficiency of the undoped perovskite solar cell in the comparative example is only 75% of the initial efficiency, and the thermal stability of the perovskite solar cell is significantly improved by introducing methyl 3-amino-2-thiophenecarboxylate as an additive in the perovskite light-absorbing layer.

[0094] Although the present application has been disclosed with reference to the preferred embodiments thereof, it is not intended to limit the application. Those skilled in the art to which the present application pertains can make various modifications and improvements without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application is defined by the appended claims.

Claims

1. A perovskite solar cell doped with 3-amino-2-thiophenecarboxylic acid methyl ester, characterized by, From bottom to top, successively include: anode substrate, hole transport layer, interface modification layer, perovskite light absorption layer, electron transport layer, hole blocking layer and cathode electrode; The perovskite light-absorbing layer is a 3-amino-2-thiophene carboxylic acid methyl ester doped perovskite layer, and the perovskite of the perovskite light-absorbing layer is composed of at least one ion from among Cs + , MA + , and FA + , and has a general formula of FA 1-x-y MA y Cs x PbI 3- z Br z (0≤x<1, 0≤y≤1, x+y≤1, 0≤z<3) The preparation method of the perovskite light absorption layer is an anti-solvent method, and the anti-solvent used is a chlorobenzene solution containing 3-amino-2-thiophene carboxylic acid methyl ester.

2. The perovskite solar cell doped with 3-amino-2-thiophenecarboxylic acid methyl ester according to claim 1, characterized in that, The perovskite of the perovskite light-absorbing layer is FA 0.83 Cs 0.17 PbI 2.7 Br 0.3 ; the anode substrate is indium tin oxide glass (ITO glass) or fluorine-doped tin oxide glass (FTO glass), the hole transport layer is poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), the interface modification layer is poly[(9,9-di(3'-(N,N-dimethylamino)propyl)fluorenyl-2,7-diyl)-ALT-[(9,9-di-n-octylfluorenyl 2,7-diyl)-bromine (PFN-Br), the electron transport layer is C 60 , the hole blocking layer is BCP, the cathode electrode is Ag or Cu, and the thickness of the cathode electrode is 60-100 nm.

3. The perovskite solar cell doped with 3-amino-2-thiophenecarboxylic acid methyl ester according to claim 1, characterized in that, The concentration of the 3-amino-2-thiophene carboxylic acid methyl ester in the anti-solvent solution is 2-5 mg / mL.

4. The method for preparing a perovskite solar cell doped with 3-amino-2-thiophenecarboxylic acid methyl ester according to any one of claims 1 to 3, characterized in that, The method comprises the following steps: (1) washing the anode substrate, and then performing surface treatment on the anode substrate to obtain a surface-treated anode surface; (2) successively spin-coating a hole transport layer and an interface modification layer on the surface-treated anode surface in step (1); (3) adding 3-amino-2-thiophene carboxylic acid methyl ester to a solvent to dissolve and obtain an anti-solvent solution; (4) spin-coating the perovskite light absorption layer on the surface of the interface modification layer in step (2); (5) successively evaporating an electron transport layer, a hole blocking layer and a cathode electrode on the surface of the perovskite light absorption layer in step (4) to obtain the perovskite solar cell doped with 3-amino-2-thiophene carboxylic acid methyl ester.

5. The method of claim 4, wherein the method of preparing a perovskite solar cell doped with methyl 3-amino-2-thiophenecarboxylate is characterized by, The surface treatment in step (1) comprises: successively ultrasonic cleaning ITO glass cleaning agent, deionized water, acetone and isopropanol for 20-30 minutes, then blowing the anode substrate dry with a nitrogen flow, and finally performing 5-10 minutes of plasma surface treatment on the surface of the cleaned and dried anode substrate by using a Plasma cleaning machine.

6. The method of claim 4, wherein the method of preparing a perovskite solar cell doped with methyl 3-amino-2-thiophenecarboxylate is characterized by, The preparation process of the hole transport layer in step (2) is: spin-coating a toluene solution of PTAA on the surface-treated anode substrate, and then performing annealing treatment to obtain the hole transport layer; wherein the spin-coating speed is 5000-6000 revolutions / minute, and the spin-coating time is 30-40 seconds; the annealing temperature is 90-110 ℃, and the annealing time is 5-10 minutes; the concentration of the PTAA toluene solution is 1.5-2.5 mg / mL.

7. The method of claim 4, wherein the method is characterized by: The preparation process of the interface modification layer in step (2) is: spin-coating a DMF solution of PFN-Br on the surface of PTAA to obtain the interface modification layer; wherein the spin-coating speed is 5000-6000 revolutions / minute, and the spin-coating time is 10-30 seconds; the solubility of the DMF solution of PFN-Br is 0.2-1.0 mg / mL.

8. The method of claim 4, wherein the method is characterized by: The preparation of the perovskite light absorption layer in step (4) comprises: I. Preparation of perovskite precursor mixed solution Add formamidinium iodide (FAI), cesium iodide (CsI), lead iodide (PbI2) and lead bromide (PbBr2) into a mixed solvent of DMF and DMSO, stir uniformly, and form a perovskite precursor mixed solution; II. Spin-coating deposition of perovskite The above perovskite precursor mixed solution is deposited on the surface of the interface modification layer through a two-stage spin-coating process, and 100-300 uL of the prepared anti-solvent solution is added dropwise at 10-20 seconds in the second stage, and the perovskite light absorption layer is obtained after annealing treatment, and the annealing temperature is 90-110 ℃, and the annealing time is 10-30 minutes; The two-stage spin coating process includes: (1) 500-1500 rpm for 5-10 seconds; (2) 5000-6000 rpm for 25-40 seconds.

9. The method of claim 8, wherein the method is characterized by: The stoichiometric ratio of FAI, CsI, PbI2 and PbBr2 is mixed in the perovskite precursor mixed solution, the concentration of halide of lead in the perovskite precursor solution is 1-1.5 M, and the volume ratio of DMF to DMSO in the perovskite precursor mixed solution is 3:1-5:

1. 0.83 Cs 0.17 PbI 2.7 Br 0.3 The stoichiometric ratio of FAI, CsI, PbI2 and PbBr2 is mixed in the perovskite precursor mixed solution, the concentration of halide of lead in the perovskite precursor solution is 1-1.5 M, and the volume ratio of DMF to DMSO in the perovskite precursor mixed solution is 3:1-5:

1.

10. The method of claim 4, wherein the method of preparing a perovskite solar cell doped with methyl 3-amino-2-thiophenecarboxylate is characterized by, The operation steps of step (5) include: first, evaporating an electron transport layer on the surface of the perovskite light-absorbing layer, with a thickness of 10-30 nm; then, evaporating a hole blocking layer on the electron transport layer, with a thickness of 5-10 nm; finally, evaporating an Ag or Cu cathode electrode, with a thickness of 60-100 nm.

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