CsPbI3 perovskite solar cell based on silane coupling agent and preparation method thereof

Abstract

The invention discloses a CsPbI3 perovskite solar cell based on a silane coupling agent and a preparation method of the CsPbI3 perovskite solar cell, and belongs to the technical field of perovskite solar cells. According to the method, a coupling agent is spin-coated between an electron transport layer and a perovskite absorption layer, and then water soaking treatment is carried out, so that the coupling agent is hydrolyzed, crosslinked and anchored on the electron transport layer, and the electron extraction and transmission capability between the electron transport layer and a perovskite layer is improved; meanwhile, C = C and C = O in the silane coupling agent can react with the bottom interface of the perovskite, so that the defect state density of the film is reduced, the non-radiative recombination loss is reduced, a molecular bridge is formed between the electron transport layer and the perovskite, crystal growth of the perovskite is optimized, the quality and thickness of the perovskite film are improved, various parameters of the perovskite are optimized, and the efficiency is improved; and the efficiency of 21.70% is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of perovskite solar cells, and in particular relates to a CsPbI3 perovskite solar cell based on a silane coupling agent and a preparation method thereof. Background Art

[0002] As energy demand continues to increase, environmental pollution caused by traditional energy sources is becoming increasingly serious, and people are paying more and more attention to clean energy. Perovskite solar cells are a member of the clean energy category. Due to their unique ABX3 structure, they have excellent photoelectric properties and are a new type of thin-film solar cell with great potential.

[0003] Currently, high-efficiency perovskite cells primarily utilize organic-inorganic hybrid perovskites as their light-absorbing layer. Organic-inorganic hybrid perovskites can achieve a high photoelectric conversion efficiency of 26%, but the temperature sensitivity of the organic component in these cells leads to poor cell stability. CsPbI3 all-inorganic perovskite cells, which do not contain organic components, offer superior heat resistance and improved stability compared to organic-inorganic hybrid perovskites. Currently, the highest efficiency of CsPbI3 perovskite cells exceeds 22%, significantly lower than that of organic-inorganic hybrid perovskite cells. This is largely due to the low electrical conductivity of TiO2 itself and the presence of numerous defects at the perovskite interface. Therefore, managing defects at the TiO2-perovskite interface is crucial in inorganic PSCs. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a CsPbI3 perovskite solar cell based on a silane coupling agent and a preparation method thereof, so as to solve the problem of low efficiency of CsPbI3 perovskite solar cells caused by high interface defects between the TiO2 electron transport layer and the perovskite light absorbing layer prepared by the prior art.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent comprises the following steps: A TiO2 electron transport layer is prepared on conductive glass, a silane coupling agent solution is spin-coated on the TiO2 electron transport layer, the spin-coating is followed by soaking in water, and vacuum drying to obtain a silane coupling agent layer on the TiO2 electron transport layer; a perovskite precursor solution is spin-coated on the silane coupling agent layer, and a perovskite absorption layer is obtained after annealing; a hole transport layer is prepared on the perovskite absorption layer, and a metal electrode is prepared on the hole transport layer; The silane coupling agent layer is a silane coupling agent (triethoxysilyl)-2-methyl acrylate C 10 H 20 O5Si, and the perovskite absorption layer is CsPbI3.

[0006] A further improvement of the present invention is: Preferably, the concentration of the silane coupling agent solution is 10 μL / mL to 70 μL / mL, and the immersion time in water after spin coating is 1-3 min.

[0007] Preferably, the spin coating speed is 3000-5000 rpm / s, and the spin coating time is 30-40 s.

[0008] Preferably, the solute of the silane coupling agent solution is C 10 H 20 O5Si, solvent is IPA.

[0009] Preferably, the concentration of the perovskite precursor solution is 0.745 M, the solutes are hydrogen lead iodide and cesium iodide, and the solvent is a mixed solution of DMF and DMSO.

[0010] Preferably, the spin coating of the perovskite precursor solution is performed in two stages: the first stage has a rotation speed of 500-1000 rpm / s and a spin coating time of 5-20 s; the second stage has a rotation speed of 2000-3000 rpm / s and a spin coating time of 30-50 s.

[0011] Preferably, the annealing temperature of the perovskite absorber layer is 160°C to 200°C, and the annealing time is 40 to 60 min.

[0012] Preferably, the hole transport layer is Spiro-OMeTAD.

[0013] Preferably, the metal electrode is a gold electrode.

[0014] A CsPbI3 perovskite solar cell based on a silane coupling agent prepared by the above preparation method comprises a conductive glass, a TiO2 electron transport layer, a silane coupling agent layer, a perovskite absorption layer, a hole transport layer and a metal electrode arranged in sequence from bottom to top.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a preparation method of a CsPbI3 perovskite solar cell based on a silane coupling agent. In the perovskite solar cell, a silane coupling agent solution is coated on the basis of a TiO2 electron transport layer. The coupling agent is liquid at room temperature and undergoes intense hydrolysis and crosslinking when mixed with a large amount of water. After coating, the perovskite solar cell with the silane coupling agent is immersed in water. During the process, the ethoxy group of the silane coupling agent connected to Si undergoes a hydrolysis reaction with H2O to form three -OH groups. The -OH groups in the adjacent hydrolyzed coupling agents react with each other to form oligomers of the coupling agent. On the other hand, there are unreacted -OH groups in the formed oligomers. The residual -OH groups react with the -OH groups on the TiO2, causing the oligomers to be anchored on the TiO2. Condensation and anchoring occur during hydrolysis, thereby reducing defects on the TiO2 surface and improving carrier extraction and transmission efficiency. Further, the silane coupling agent C 10 H 20 The C=C and C=O present in O5Si will interact with the perovskite lattice, so that during the formation process of the perovskite absorption layer, the perovskite defects can be passivated to reduce the film defect state density, reduce non-radiative recombination losses, and improve the battery efficiency. As a result, the coupling agent forms a molecular bridge between TiO2 and the perovskite. While the coupling agent agglomerates and condenses on the TiO2 surface, it can optimize the crystallization quality of the perovskite and increase the thickness of the perovskite film. Therefore, the all-inorganic CsPbI3 perovskite battery based on this process has a photoelectric conversion efficiency increased from 19.54% to 21.70%, the opening voltage increased from 1.23 V to 1.26 V, the filling increased from 77.84% to 81.86%, and the current increase was particularly significant from 20.35 mA / cm 2 Increased to 20.98 mA / cm 2 . BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the structure of the CsPbI3 perovskite solar cell described in Example 1 of the present invention; Among them: 1 is FTO layer, 2 is electron transport layer, 3 is coupling agent layer, 4 is perovskite light absorption layer, 5 is hole transport layer, and 6 is metal electrode; Figure 2 The unmodified and lower interface modified C described in Example 1 of the present invention 10 H 20 Performance comparison of inorganic perovskite solar cells after adding O5Si coupling agent; Figure 3 The unmodified and lower interface modified C described in Example 1 of the present invention 10 H 20 XRD comparison diagram of perovskite light absorbing layer after O5Si coupling agent; Figure 4The unmodified and lower interface modified C described in Example 1 of the present invention 10 H 20 UV comparison of perovskite light absorbing layer after O5Si coupling agent; Figure 5 The unmodified and lower interface modified C described in Example 1 of the present invention 10 H 20 EQE comparison of perovskite light absorbing layer after O5Si coupling agent; Figure 6 The unmodified and lower interface modified C described in Example 1 of the present invention 10 H 20 PL comparison of perovskite light absorbing layer after O5Si coupling agent; Figure 7 The infrared comparison diagram is shown in Figure 2. (a) C coated on TiO2 without and after treatment 10 H 20 O5Si coupling agent; (b) The picture shows pure C 10 H 20 O5Si coupling agent added PbI2 C 10 H 20 Infrared comparison of O5Si coupling agent samples; Figure 8 The planar and cross-sectional SEM images, where (a) and (c) are images without spin-coating coupling agent; (b) and (d) are images with spin-coating coupling agent. DETAILED DESCRIPTION

[0017] The present invention is described in further detail below with reference to the accompanying drawings: To facilitate understanding of the features and effects of the present invention by those skilled in the art, the following provides a general description and definition of the terms and expressions used in the specification and claims. Unless otherwise indicated, all technical and scientific terms used herein have the ordinary meanings as understood by those skilled in the art regarding the present invention. In the event of conflict, the definitions in this specification shall prevail.

[0018] In this document, unless otherwise specified, “include,” “including,” “contains,” “has” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0019] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0020] The following examples were prepared using conventional instruments and equipment in the art. Experimental methods in the following examples, where specific conditions are not specified, were generally performed under conventional conditions or according to the conditions recommended by the manufacturer. The various raw materials used in the following examples, unless otherwise specified, were conventional commercially available products, with specifications conventional in the art. In the present specification and the following examples, unless otherwise specified, "%" indicates percentage by weight, "part" indicates parts by weight, and "ratio" indicates weight ratio.

[0021] The present invention discloses a method for optimizing CsPbI3 perovskite cells by using silane coupling agent materials, comprising the following steps: Step 1, cleaning the conductive glass substrate; The conductive glass substrate is fluorine-doped tin oxide (FTO) conductive glass, which is ultrasonically cleaned in ultrapure water with glass cleaning agent for 10 to 30 minutes, and the ultrapure water is replaced every 30 minutes to clean the residual cleaning agent on the glass. Then, the conductive glass is blown dry with a nitrogen gun.

[0022] Step 2, preparing an electron transport layer; An electron transport layer (ETL) was deposited on a conductive glass substrate using TiO2 via water-bath deposition for 40 minutes to 1 hour. The FTO glass was treated with UV-ozone for 15 minutes. 4.5 mL of TiCl4 was dropped onto 200 mL of ice. Once the ice melted, the layer was placed in a 70°C oven for deposition. The resulting TiO2 ETL had a thickness of 40 to 50 nm.

[0023] Step 3, preparing a silane coupling agent layer; (1) Prepare silane coupling agent solution; 10 H 20 O5Si was added to IPA solvent to prepare an alkane coupling agent solution with a solubility of 10 μL / mL~70 μL / mL.

[0024] (2) Spin coating the silane coupling agent solution on the surface of the electron transport layer at a spin coating speed of 3000-5000 rpm / s for 30-40 s; soaking the surface in ultrapure water for 1-3 min to achieve complete hydrolysis and cross-linking of the coupling agent; and drying the surface in a vacuum drying oven at 100 °C for 10 min. Step 4, preparing an all-inorganic perovskite absorption layer; (1) Preparation of an all-inorganic perovskite precursor solution: Hydrogen lead iodide (HPbI3) and cesium iodide (CsI) (n:n = 0.745:0.825) were dissolved in a mixed solvent of DMF and DMSO (V / V = 8.5 / 1.5) to prepare a CsPbI3 perovskite precursor solution with a concentration of 0.745 M. The perovskite precursor solution was stirred for 4 h and then filtered through a 0.45 μm filter cartridge for later use.

[0025] (2) The all-inorganic perovskite precursor solution is spin-coated on the silane coupling agent layer in two stages: the first stage has a rotation speed of 500~1000 rpm / s and a spin coating time of 5~20 s; the second stage has a rotation speed of 2000~3000 rpm / s and a spin coating time of 30~50 s; after spin coating, annealing treatment is performed; the annealing temperature is 160℃~200℃ and the annealing time is 40~60 min to obtain the perovskite absorption layer.

[0026] Step 5, preparing a hole transport layer; A hole transport layer was prepared on the thin film prepared in step 4 by spin coating. Spiro-OMeTAD powder (90 mg), lithium salt (22 μL), and t-BP (36 μL) were dissolved in 1 mL of chlorobenzene to obtain a Spiro-OMeTAD solution. The spin coating speed was 5000 rpm / s and the spin coating time was 40 s to prepare the hole transport layer.

[0027] Step 6, evaporating electrodes; A gold electrode with a thickness of 80-100 nm was evaporated on the hole transport layer prepared in step 5. The cell area was 0.09 cm 2 , and obtain perovskite solar cells.

[0028] The battery structure prepared by the above method includes conductive glass, electron transport layer, silane coupling agent material layer, perovskite absorption layer, hole transport layer and metal electrode stacked in sequence from bottom to top.

[0029] The following is further explained with reference to specific embodiments and comparative examples.

[0030] Comparative Example Step 1: Ultrasonic clean the conductive glass in ultrapure water with glass detergent for 30 minutes, replace the ultrapure water every 30 minutes to clean the residual detergent on the glass, and then blow dry the conductive glass with a nitrogen gun.

[0031] In step 2, a layer of TiO2 was deposited as an electron transport layer on the cleaned FTO glass using a hydrothermal deposition method in a 70°C oven for 55 minutes. The FTO glass was treated with UV-ozone for 15 minutes. 4.5 mL of TiCl4 was dropped onto 200 mL of ice. After the ice melted to a thumb-sized size, it was placed in a 70°C oven for deposition. The resulting TiO2 electron transport layer had a thickness of 40-50 nm.

[0032] Step 3: Dissolve hydrogen lead iodide (HPbI3) and cesium iodide (CsI) (n:n = 0.745:0.825) in a mixed solvent of DMF and DMSO (V / V = 8.5 / 1.5) to prepare a CsPbI3 perovskite precursor solution with a concentration of 0.745 M. Stir the perovskite precursor solution for 4 h and then filter it through a 0.45 μm filter cartridge for later use.

[0033] In step 4, the prepared inorganic CsPbI3 perovskite precursor solution is spin-coated on the electron transport layer to prepare the perovskite absorption layer; the spin coating process is divided into two stages: the first stage has a rotation speed of 1000 rpm / s and a spin coating time of 10 s; the second stage has a rotation speed of 3000 rpm / s and a spin coating time of 40 s; the annealing process is annealing on a hot plate at 170 °C for 50 min.

[0034] Step 4: Spin-coat the hole transport layer Spiro-OMeTAD on the perovskite layer by spin coating. Dissolve Spiro-OMeTAD powder (90 mg), lithium salt (22 μL), and t-BP (36 μL) in 1 mL of chlorobenzene to obtain a Spiro-OMeTAD solution with a concentration of 90 mg / mL. Spin coating at a speed of 5000 rpm / s for 40 s to obtain a hole transport layer.

[0035] Step 5: Evaporate an 80 nm thick gold film on the hole transport layer Spiro-OMeTAD. The cell area is 0.09 cm 2 , and obtain perovskite solar cells.

[0036] Example 1 Step 1: Ultrasonic clean the conductive glass in ultrapure water with glass detergent for 30 minutes, replace the ultrapure water every 30 minutes to clean the residual detergent on the glass, and then blow dry the conductive glass with a nitrogen gun.

[0037] In step 2, a layer of TiO2 was deposited as an electron transport layer on the cleaned FTO glass using a hydrothermal deposition method in a 70°C oven for 55 minutes. The FTO glass was treated with UV-ozone for 15 minutes. 4.5 mL of TiCl4 was dropped onto 200 mL of ice. After the ice melted to a thumb-sized size, the layer was placed in a 70°C oven for deposition. The resulting TiO2 electron transport layer had a thickness of 40-50 nm.

[0038] Step 3: Silane coupling agent layer C 10 H 20 O5Si (50 μL) was dissolved in 1 mL IPA to prepare a coupling agent solution, which was then spin-coated on the TiO2 electron transport layer at a speed of 3000 rpm / s for 30 s. The solution was then immersed in ultrapure water for 1 min and dried in a vacuum drying oven at 100 °C for 10 min. Step 4: Dissolve hydrogen lead iodide (HPbI3) and cesium iodide (CsI) (n:n = 0.745:0.825) in a mixed solvent of DMF and DMSO (V / V = 8.5 / 1.5) to prepare a CsPbI3 perovskite precursor solution with a concentration of 0.745 M. Stir the perovskite precursor solution for 4 h and then filter it through a 0.45 μm filter cartridge for later use. In step 5, the prepared inorganic CsPbI3 perovskite precursor solution is spin-coated on the surface of the silane coupling agent material layer to prepare the perovskite absorption layer; the spin coating process is divided into two stages: the first stage has a rotation speed of 1000 rpm / s and a spin coating time of 10 s; the second stage has a rotation speed of 3000 rpm / s and a spin coating time of 40 s; the annealing process is annealing on a hot plate at 170 °C for 50 min.

[0039] Step 6: Spin-coat the hole transport layer Spiro-OMeTAD on the perovskite layer using a spin coating method. Dissolve Spiro-OMeTAD powder (90 mg), lithium salt (22 μL), and t-BP (36 μL) in 1 mL of chlorobenzene to obtain a Spiro-OMeTAD solution. The concentration of the Spiro-OMeTAD solution is 90 mg / mL. The spin coating speed is 5000 rpm / s, and the spin coating time is 40 s to prepare the hole transport layer.

[0040] Step 7: Vapor-deposit an 80 nm thick gold film on the hole transport layer Spiro-OMeTAD, with a cell area of 0.09 cm2, to obtain a perovskite solar cell.

[0041] like Figure 1Figure 1 shows the schematic diagram of the structure of an inorganic perovskite solar cell. In the figure, 1 is the FTO layer, 2 is the electron transport layer, 3 is the coupling agent modified layer, 4 is the perovskite light absorption layer, 5 is the hole transport layer, and 6 is the metal electrode. The concentration of the coupling agent is 50 μL / mL.

[0042] like Figure 2 As shown in the figure, the performance comparison of the perovskite film using the process of spin-coating the coupling agent modified layer in this embodiment and the perovskite solar cell without the process of spin-coating the coupling agent modified layer in the comparative example is shown. It can be seen from the figure that the photoelectric conversion efficiency of the all-inorganic CsPbI3 perovskite cell based on this process is improved from 19.54% to 21.70%, the opening voltage is increased from 1.23 V to 1.26 V, the filling is increased from 77.84% to 81.86%, and the current is increased significantly from 20.35 mA / cm 2 Increased to 20.98 mA / cm 2 .

[0043] like Figure 3 As shown in Figure 2, the XRD patterns of the perovskite film in this embodiment using a spin-coated coupling agent modification layer are compared with the perovskite film in the comparative example using no spin-coated coupling agent modification layer. The figure shows that the perovskite diffraction peak intensity increases after the coupling agent layer is spin-coated, indicating that the crystallinity of the perovskite film is enhanced.

[0044] like Figure 4 As shown in FIG. 1 , a UV image of a perovskite film in this embodiment using a spin-coated coupling agent modification layer is compared with a perovskite film in a comparative example that does not use a spin-coated coupling agent modification layer. It can be seen from the figure that the light absorption capacity of the perovskite is improved after the spin-coating coupling agent layer is applied. like Figure 5 As shown in the figure, the EQE graph of the perovskite film using the process of spin-coating the coupling agent modification layer in this embodiment is compared with the perovskite film in the comparative example without the process of spin-coating the coupling agent modification layer. It can be seen from the figure that after the process of spin-coating the coupling agent layer, the photon conversion efficiency of the perovskite cell is significantly improved, so that the current density is increased from 20.26 mA / cm 2 Increased to 20.81 mA / cm 2 .

[0045] like Figure 6 Figure 2 shows a comparison of the PL images of the perovskite film in this example using a spin-coated coupling agent modification layer and the perovskite film in the comparative example without a spin-coated coupling agent modification layer. The figure shows that the fluorescence intensity of the perovskite film is significantly suppressed after the coupling agent layer is spin-coated, indicating that the optimization has reduced non-radiative recombination in the perovskite film.

[0046] like Figure 7 As shown, spin-coated on TiO2 C10 H 20 O5 Si Comparison of infrared images of coupling agent without and with process (a) and pure C 10 H 20 O5 Si Coupling agent and PbI2-added C 10 H 20 O5 Si Comparison of infrared images of coupling agent samples (b). As can be seen from (a), the C 10 H 20 O5 Si The coupling agent has a characteristic peak of -OH in the 3600-3800 range, indicating that the ethoxy group of the coupling agent has been hydrolyzed to produce -OH after the process treatment; and the Si-O characteristic peak in the coupling agent has shifted from 1150 to 1159 after the treatment, indicating that the -OH connected to Si after hydrolysis reacts with the -OH on TiO2, making the coupling agent anchored on TiO2; at the same time, the Si-O-Si bond characteristic peak also appeared at 1061, indicating that the coupling agent molecules after hydrolysis have undergone dehydration polymerization to form oligomers. As can be seen from Figure (b), PbI2+C 10 H 20 O5 Si The characteristic peaks of C=O and C=C in the sample were significantly blue-shifted, from 1720 cm -1 Shift to 1709 cm -1 and from 1629 cm -1 Shift to 1617 cm -1 , proves that C 10 H 20 O5 Si Strong interaction between coupling agent and PbI2.

[0047] like Figure 8 Shown are plan and cross-sectional SEM images of the film without (a) (c) and with (b) (d) the coupling agent. The plan view shows that after the coupling agent is applied, the perovskite crystallizes with a smoother top surface and smaller pinholes, optimizing the contact between the perovskite and the hole transport layer and reducing non-radiative recombination. The cross-sectional view shows that the perovskite film becomes significantly thicker after the coupling agent is applied, compared to the CT film, resulting in a significant increase in current.

[0048] Example 2 In this example, the concentration of the silane coupling agent is 10 μL / mL, and the other steps are the same as those in Example 1. In this example, the efficiency of the inorganic perovskite solar cell is 20.6%.

[0049] Example 3 In this example, the concentration of the silane coupling agent is 30 μL / mL, and the other steps are the same as those in Example 1. In this example, the efficiency of the inorganic perovskite solar cell is 20.91%.

[0050] Example 4 In this example, the concentration of the silane coupling agent is 70 μL / mL, and the other steps are the same as those in Example 1. In this example, the efficiency of the inorganic perovskite solar cell is 21.21%.

[0051] Example 5 Step 1: Ultrasonic clean the conductive glass in ultrapure water with glass detergent for 20 minutes, replace the ultrapure water every 30 minutes to clean the residual detergent on the glass, and then blow dry the conductive glass with a nitrogen gun.

[0052] In step 2, a layer of TiO2 was deposited as an electron transport layer on the cleaned FTO glass using a hydrothermal deposition method in a 70°C oven for 55 minutes. The FTO glass was treated with UV-ozone for 15 minutes. 4.5 mL of TiCl4 was dropped onto 200 mL of ice. After the ice melted to a thumb-sized size, the layer was placed in a 70°C oven for deposition. The resulting TiO2 electron transport layer had a thickness of 40-50 nm.

[0053] Step 3: Dissolve the silane coupling agent layer (50 μL) in 1 mL of IPA to prepare a solution, which is then spin-coated on the TiO2 electron transport layer at a speed of 3000 rpm / s for 30 s. Soak the solution in ultrapure water for 2 min and dry it in a vacuum drying oven at 100 °C for 10 min. Step 4: Dissolve hydrogen lead iodide (HPbI3) and cesium iodide (CsI) (n:n = 0.745:0.825) in a mixed solvent of DMF and DMSO (V / V = 8.5 / 1.5) to prepare a CsPbI3 perovskite precursor solution with a concentration of 0.745 M. Stir the perovskite precursor solution for 4 h and then filter it through a 0.45 μm filter cartridge for later use. In step 5, the prepared inorganic CsPbI3 perovskite precursor solution is spin-coated on the surface of the silane coupling agent material layer to prepare the perovskite absorption layer; the spin coating process is divided into two stages: the first stage has a rotation speed of 1000 rpm / s and a spin coating time of 10 s; the second stage has a rotation speed of 3000 rpm / s and a spin coating time of 40 s; the annealing process is annealing on a hot plate at 170 °C for 50 min.

[0054] Step 6: Spin-coat the hole transport layer Spiro-OMeTAD on the perovskite layer using a spin coating method. Dissolve Spiro-OMeTAD powder (90 mg), lithium salt (22 μL), and t-BP (36 μL) in 1 mL of chlorobenzene to obtain a Spiro-OMeTAD solution. The concentration of the Spiro-OMeTAD solution is 90 mg / mL. The spin coating speed is 5000 rpm / s, and the spin coating time is 40 s to prepare the hole transport layer.

[0055] Step 7: Evaporate an 80 nm thick gold film on the hole transport layer Spiro-OMeTAD. The cell area is 0.09 cm 2 , and obtain perovskite solar cells.

[0056] Example 5 Step 1: Ultrasonic clean the conductive glass in ultrapure water with glass detergent for 20 minutes, replace the ultrapure water every 30 minutes to clean the residual detergent on the glass, and then blow dry the conductive glass with a nitrogen gun.

[0057] In step 2, a layer of TiO2 was deposited as an electron transport layer on the cleaned FTO glass using a hydrothermal deposition method in a 70°C oven for 55 minutes. The FTO glass was treated with UV-ozone for 15 minutes. 4.5 mL of TiCl4 was dropped onto 200 mL of ice. After the ice melted to a thumb-sized size, the layer was placed in a 70°C oven for deposition. The resulting TiO2 electron transport layer had a thickness of 40-50 nm.

[0058] Step 3: Dissolve the silane coupling agent layer (50 μL) in 1 mL of IPA to prepare a solution, which is then spin-coated on the TiO2 electron transport layer at a speed of 3000 rpm / s for 30 s. Soak the solution in ultrapure water for 3 min and dry it in a vacuum drying oven at 100 °C for 10 min. Step 4: Dissolve hydrogen lead iodide (HPbI3) and cesium iodide (CsI) (n:n = 0.745:0.825) in a mixed solvent of DMF and DMSO (V / V = 8.5 / 1.5) to prepare a CsPbI3 perovskite precursor solution with a concentration of 0.745 M. Stir the perovskite precursor solution for 4 h and then filter it through a 0.45 μm filter cartridge for later use. In step 5, the prepared inorganic CsPbI3 perovskite precursor solution is spin-coated on the surface of the silane coupling agent material layer to prepare the perovskite absorption layer; the spin coating process is divided into two stages: the first stage has a rotation speed of 1000 rpm / s and a spin coating time of 10 s; the second stage has a rotation speed of 3000 rpm / s and a spin coating time of 40 s; the annealing process is annealing on a hot plate at 170 °C for 50 min.

[0059] Step 6: Spin-coat the hole transport layer Spiro-OMeTAD on the perovskite layer using a spin coating method. Dissolve Spiro-OMeTAD powder (90 mg), lithium salt (22 μL), and t-BP (36 μL) in 1 mL of chlorobenzene to obtain a Spiro-OMeTAD solution. The concentration of the Spiro-OMeTAD solution is 90 mg / mL. The spin coating speed is 5000 rpm / s, and the spin coating time is 40 s to prepare the hole transport layer.

[0060] Step 7: Evaporate an 80 nm thick gold film on the hole transport layer Spiro-OMeTAD. The cell area is 0.09 cm 2 , and obtain perovskite solar cells.

[0061] Example 6 Step 1: Ultrasonic clean the conductive glass in ultrapure water with glass detergent for 20 minutes, replace the ultrapure water every 30 minutes to clean the residual detergent on the glass, and then blow dry the conductive glass with a nitrogen gun.

[0062] In step 2, a layer of TiO2 was deposited as an electron transport layer on the cleaned FTO glass using a hydrothermal deposition method in a 70°C oven for 55 minutes. The FTO glass was treated with UV-ozone for 15 minutes. 4.5 mL of TiCl4 was dropped onto 200 mL of ice. After the ice melted to a thumb-sized size, the layer was placed in a 70°C oven for deposition. The resulting TiO2 electron transport layer had a thickness of 40-50 nm.

[0063] Step 3: Dissolve the silane coupling agent layer (50 μL) in 1 mL of IPA to prepare a solution, which is then spin-coated on the TiO2 electron transport layer at a speed of 4000 rpm / s for 40 s. Soak the solution in ultrapure water for 1 min, and dry it in a vacuum drying oven at 100 °C for 10 min. Step 4: Dissolve hydrogen lead iodide (HPbI3) and cesium iodide (CsI) (n:n = 0.745:0.825) in a mixed solvent of DMF and DMSO (V / V = 8.5 / 1.5) to prepare a CsPbI3 perovskite precursor solution with a concentration of 0.745 M. Stir the perovskite precursor solution for 4 h and then filter it through a 0.45 μm filter cartridge for later use. In step 5, the prepared inorganic CsPbI3 perovskite precursor solution is spin-coated on the surface of the silane coupling agent material layer to prepare the perovskite absorption layer; the spin coating process is divided into two stages: the first stage has a rotation speed of 1000 rpm / s and a spin coating time of 10 s; the second stage has a rotation speed of 3000 rpm / s and a spin coating time of 40 s; the annealing process is annealing on a hot plate at 170 °C for 50 min.

[0064] Step 6: Spin-coat the hole transport layer Spiro-OMeTAD on the perovskite layer using a spin coating method. Dissolve Spiro-OMeTAD powder (90 mg), lithium salt (22 μL), and t-BP (36 μL) in 1 mL of chlorobenzene to obtain a Spiro-OMeTAD solution. The concentration of the Spiro-OMeTAD solution is 90 mg / mL. The spin coating speed is 5000 rpm / s, and the spin coating time is 40 s to prepare the hole transport layer.

[0065] Step 7: Evaporate an 80 nm thick gold film on the hole transport layer Spiro-OMeTAD. The cell area is 0.09 cm 2 , and obtain perovskite solar cells.

[0066] Example 7 Step 1: Ultrasonic clean the conductive glass in ultrapure water with glass detergent for 20 minutes, replace the ultrapure water every 30 minutes to clean the residual detergent on the glass, and then blow dry the conductive glass with a nitrogen gun.

[0067] In step 2, a layer of TiO2 was deposited as an electron transport layer on the cleaned FTO glass using a hydrothermal deposition method in a 70°C oven for 55 minutes. The FTO glass was treated with UV-ozone for 15 minutes. 4.5 mL of TiCl4 was dropped onto 200 mL of ice. After the ice melted to a thumb-sized size, the layer was placed in a 70°C oven for deposition. The resulting TiO2 electron transport layer had a thickness of 40-50 nm.

[0068] Step 3: Dissolve the silane coupling agent layer (50 μL) in 1 mL of IPA to prepare a solution, and spin-coat it on the TiO2 electron transport layer at a speed of 5000 rpm / s for 30 s; soak it in ultrapure water for 1 min; and dry it in a vacuum drying oven at 100 °C for 10 min. Step 4: Dissolve hydrogen lead iodide (HPbI3) and cesium iodide (CsI) (n:n = 0.745:0.825) in a mixed solvent of DMF and DMSO (V / V = 8.5 / 1.5) to prepare a CsPbI3 perovskite precursor solution with a concentration of 0.745 M. Stir the perovskite precursor solution for 4 h and then filter it through a 0.45 μm filter cartridge for later use. In step 5, the prepared inorganic CsPbI3 perovskite precursor solution is spin-coated on the surface of the silane coupling agent material layer to prepare the perovskite absorption layer; the spin coating process is divided into two stages: the first stage has a rotation speed of 1000 rpm / s and a spin coating time of 10 s; the second stage has a rotation speed of 3000 rpm / s and a spin coating time of 40 s; the annealing process is annealing on a hot plate at 170 °C for 50 min.

[0069] Step 6: Spin-coat the hole transport layer Spiro-OMeTAD on the perovskite layer using a spin coating method. Dissolve Spiro-OMeTAD powder (90 mg), lithium salt (22 μL), and t-BP (36 μL) in 1 mL of chlorobenzene to obtain a Spiro-OMeTAD solution. The concentration of the Spiro-OMeTAD solution is 90 mg / mL. The spin coating speed is 5000 rpm / s, and the spin coating time is 40 s to prepare the hole transport layer.

[0070] Step 7: Evaporate an 80 nm thick gold film on the hole transport layer Spiro-OMeTAD. The cell area is 0.09 cm 2 , and obtain a perovskite solar cell. Example 12 In this embodiment, the spin coating and annealing parameters of the perovskite precursor solution are as follows: a first-stage rotation speed of 500 rpm / s and a spin coating time of 20 s; a second-stage rotation speed of 2000 rpm / s and a spin coating time of 50 s; and an annealing process of annealing on a hot plate at 160°C for 60 min. The remaining steps and parameters are the same as those in Example 1.

[0071] Example 8 In this embodiment, the spin coating and annealing parameters of the perovskite precursor solution are as follows: a first-stage rotation speed of 800 rpm / s and a spin coating time of 10 s; a second-stage rotation speed of 2500 rpm / s and a spin coating time of 40 s; and an annealing process of annealing at a 180°C hot plate for 50 min. The remaining steps and parameters are the same as those in Example 1.

[0072] Example 9 In this embodiment, the spin coating and annealing parameters of the perovskite precursor solution are as follows: a first-stage rotation speed of 1000 rpm / s and a spin coating time of 5 s; a second-stage rotation speed of 2000 rpm / s and a spin coating time of 50 s; and an annealing process of annealing on a hot plate at 200°C for 40 min. The remaining steps and parameters are the same as those in Example 1.

[0073] Example 10 In this embodiment, the spin coating and annealing parameters of the perovskite precursor solution are as follows: a first-stage rotation speed of 1000 rpm / s and a spin coating time of 10 s; a second-stage rotation speed of 3000 rpm / s and a spin coating time of 40 s; and an annealing process of annealing at a 190°C hot plate for 50 min. The remaining steps and parameters are the same as those in Example 1.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent, characterized in that: The following steps are involved: A TiO2 electron transport layer is prepared on a conductive glass, a silane coupling agent solution is spin-coated on the TiO2 electron transport layer, the TiO2 electron transport layer is immersed in water after spin coating, and a silane coupling agent layer is prepared on the TiO2 electron transport layer after vacuum drying; A perovskite precursor solution is spin-coated on the silane coupling agent layer, and a perovskite absorption layer is obtained after annealing. A hole transport layer is prepared on the perovskite absorption layer, and a metal electrode is prepared on the hole transport layer. The silane coupling agent layer is a silane coupling agent (triethoxysilyl)-2-methyl acrylate C 10 H 20 O5Si, and the perovskite absorption layer is CsPbI3.

2. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 1, characterized in that: The concentration of the silane coupling agent solution is 10 μL / mL to 70 μL / mL, and the silane coupling agent solution is immersed in water for 1 to 3 minutes after spin coating.

3. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 2, wherein: The spin coating speed is 3000~5000 rpm / s, and the spin coating time is 30~40 s.

4. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 2, wherein: The solute of the silane coupling agent solution is C 10 H 20 O5Si, solvent is IPA.

5. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 1, wherein: The concentration of the perovskite precursor solution is 0.745 M, the solutes are hydrogen lead iodine and cesium iodide, and the solvent is a mixed solution of DMF and DMSO.

6. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 1, characterized in that: The spin coating of the perovskite precursor solution is carried out in two stages: the first stage has a rotation speed of 500-1000 rpm / s and a spin coating time of 5-20 s; the second stage has a rotation speed of 2000-3000 rpm / s and a spin coating time of 30-50 s.

7. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 1, characterized in that: The annealing temperature of the perovskite absorber layer is 160 ℃~200 ℃, and the annealing time is 40~60 min.

8. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 1, characterized in that: The hole transport layer is Spiro-OMeTAD.

9. The method for preparing a CsPbI3 perovskite solar cell based on a silane coupling agent according to claim 1, characterized in that: The metal electrode is a gold electrode.

10. A CsPbI3 perovskite solar cell based on a silane coupling agent prepared by the preparation method according to any one of claims 1 to 9, characterized in that: The invention comprises conductive glass, a TiO2 electron transport layer, a silane coupling agent layer, a perovskite absorption layer, a hole transport layer and a metal electrode which are arranged in sequence from bottom to top.

Images