Interface uniform perovskite solar cell of hole transport layer

Abstract

This invention discloses a hole transport layer with uniform interface distribution and a perovskite solar cell. The uniformly distributed hole transport layer comprises: a vanadium oxide layer disposed on the upper surface of an ITO glass substrate; a nickel oxide layer disposed on the upper surface of the vanadium oxide layer; and a self-assembled monolayer disposed on the upper surface of the nickel oxide layer. The hole transport layer provided by this invention includes VO x Layer, NiO x Layer and SAM layer, by bonding NiO to an ITO glass substrate. x Introducing an ultrathin VO layer between the layers x Layers were constructed to create ITO / VO4 with continuous energy levels and high chemical reactivity. x / NiO x The interface solves the ITO / NiO problem. x The uneven distribution of SAMs at the interface, high hole transport loss, and poor stability have been addressed. This study significantly improves the photoelectric conversion efficiency and operational stability of semi-transparent perovskite solar cells, providing an improvement strategy for perovskite / silicon tandem solar cells.

Description

Technical Field

[0001] This invention belongs to the field of hole transport layer technology, specifically relating to a hole transport layer with uniform interface distribution and a perovskite solar cell. Background Technology

[0002] In the 21st century, with the increasing prominence of energy and environmental issues, the demand for clean energy has continued to rise, and solar energy, as an emerging renewable energy source, has received widespread attention. Among the many photovoltaic materials that utilize solar energy, perovskite solar cells have become a research hotspot in the photovoltaic field due to their low cost and excellent photoelectric performance.

[0003] Currently, single-junction perovskite solar cells often employ self-assembled monolayers (SAMs) as hole transport layer materials. These SAMs leverage their tunable interface energy levels and suppression of carrier recombination to improve the power conversion efficiency (PCE) of perovskite cells. However, in the mainstream indium tin oxide / nickel oxide (ITO / NiO)... x In hole transport interfaces, achieving uniform, dense, and stable deposition of SAM remains a significant challenge, stemming from the inherent limitations of NiO. x The "inherent trade-off" of film thickness: when NiO x When the layer is too thin, although it can maintain high optical transmittance, the surface hydroxyl (-OH) density is insufficient, lacking chemical anchoring sites for binding with SAM molecules (such as 4PADCB), leading to SAM agglomeration, poor adhesion, and increased interfacial carrier transport impedance; when NiO x When the NiO layer is too thick, its absorption of visible light is enhanced, which significantly reduces the light flux entering the perovskite light-absorbing layer. Simultaneously, an excessively thick NiO layer... x This increases the hole transport path length, leading to increased carrier transport losses and ultimately reducing the battery's conversion efficiency. Summary of the Invention

[0004] The technical problem to be solved by this invention is to address the above-mentioned shortcomings in the prior art by providing a hole transport layer with uniform interface distribution and a perovskite solar cell, through ITO / NiO x A vanadium oxide layer (VO) is added to the interface. x ), making NiO x The more uniform distribution of SAM molecules on the surface improves the photoelectric conversion efficiency and stability of perovskite solar cells.

[0005] A first aspect of the present invention is to provide a hole transport layer with a uniform interface distribution, comprising: A vanadium oxide layer is disposed on the upper surface of an ITO glass substrate; A nickel oxide layer is disposed on the upper surface of the vanadium oxide layer; A self-assembled monolayer is disposed on the upper surface of the nickel oxide layer.

[0006] According to the above scheme, the thickness of the vanadium oxide layer is 2-50 nm.

[0007] According to the above scheme, the thickness of the nickel oxide layer is 20-50 nm.

[0008] According to the above scheme, the self-assembled monolayer is (4-(7H-dibenzo[c,g]carbazole-7-yl)butyl)phosphonic acid (4PADCB).

[0009] A second aspect of the present invention is to provide a method for preparing a hole transport layer with uniform interface distribution as described above, the specific steps of which are as follows: 1) A vanadium oxide layer and a nickel oxide layer are sequentially deposited on the surface of a pretreated ITO glass substrate to obtain a composite interface; 2) Dissolve SAM in an organic solvent to obtain a crude solution, filter to remove agglomerates, and obtain a SAM solution. Coat the obtained SAM solution onto the composite interface surface obtained in step 1), and anneal it to obtain a hole transport layer with uniform interface distribution on the surface of the ITO glass substrate.

[0010] According to the above scheme, the method for pretreatment of ITO glass substrate in step 1) is as follows: ultrasonically clean the ITO glass substrate in sequence with neutral detergent, deionized water and anhydrous ethanol for 5-15 minutes each time. After cleaning, dry it with high-purity nitrogen gas, and then place it in a UV ozone cleaner for 5-15 minutes.

[0011] According to the above scheme, step 1) involves depositing vanadium oxide and nickel oxide layers using either magnetron sputtering or chemical vapor deposition.

[0012] According to the above scheme, the organic solvent in step 2) is ethanol.

[0013] According to the above scheme, the concentration of the SAM solution in step 2) is 0.3-0.7 mg / mL.

[0014] According to the above scheme, the method for removing aggregates in step 2) is as follows: first, use a syringe to draw up the crude solution, and then use a needle filter with a pore size of 0.3µm to filter out the SAM solution under pressure.

[0015] According to the above scheme, step 2) involves coating the SAM solution onto the composite interface surface using a spin-coating method, with the amount of SAM solution applied to the composite interface surface being 40-80 μL / cm. 2 The spin coating speed is 3000-6000 rpm, and the spin coating time is 30-40 seconds.

[0016] According to the above scheme, the annealing process conditions for step 2) are: heating at 100-150℃ for 10-15 minutes.

[0017] A third aspect of the present invention is to provide a semi-transparent perovskite solar cell containing a hole transport layer with a uniformly distributed interface as described above.

[0018] According to the above scheme, the semi-transparent perovskite solar cell includes an ITO glass substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and a transparent electrode stacked in sequence.

[0019] The fourth aspect of the present invention is to provide a method for preparing the above-mentioned semi-transparent perovskite solar cell, comprising the following steps: after preparing a hole transport layer on the surface of an ITO glass substrate, a perovskite light-absorbing layer, an electron transport layer and a transparent electrode are prepared sequentially to obtain a semi-transparent perovskite solar cell.

[0020] This invention involves bonding NiO to an ITO glass substrate. x An ultrathin vanadium oxide layer (VO2) is added to the interface. x ), construct VO x -NiO x The hybrid interface, on the one hand, compensates for the shortcomings of NiO x Surface defects of the layer, on the other hand, hydroxyl-rich VO x This provides abundant reaction sites for SAM anchoring, compensating for the lack of NiO. x Insufficient surface reactivity makes NiO x The more uniform distribution of SAM molecules on the surface improves the stability of solar cell devices. Additionally, VO x -NiO x Hybrid interface relative to NiO x The higher light transmittance of the layer improves the photoelectric conversion efficiency of the solar cell.

[0021] The beneficial effects of the present invention are as follows: 1. The hole transport layer provided by the present invention includes VO x Layer, NiO x Layer and SAM layer, by bonding NiO to an ITO glass substrate. x Introducing an ultrathin VO layer between the layers x Layers were constructed to create ITO / VO4 with continuous energy levels and high chemical reactivity. x / NiO x The interface solves the ITO / NiO problem. x The invention addresses the problems of uneven SAM distribution, high hole transport loss, and poor stability at the interface, significantly improving the photoelectric conversion efficiency and operational stability of semi-transparent perovskite solar cells, and providing an improvement strategy for perovskite / silicon tandem solar cells. 2. The preparation method of this invention is relatively simple and has the potential for mass production. Attached Figure Description

[0022] Figure 1 The O 1s energy spectrum of the hole transport layer prepared in Comparative Example 1 and Example 1 of this invention; Figure 2 ITO / VO for the hole transport layer in Example 1 x -NiO x Energy dispersive spectroscopy (EDS) of Ni and V elements at the composite interface; Figure 3 The p 2p energy spectrum of the hole transport layer prepared in Comparative Example 1 and Example 1; Figure 4 Surface potential distribution and fluctuation curves of hole transport layers prepared in Comparative Example 1 and Example 1; Figure 5 Scanning electron microscope images of the perovskite light-absorbing layers further prepared on the hole transport layer in Comparative Example 1 and Example 1; Figure 6 The XRD patterns are of the perovskite light-absorbing layers further prepared on the hole transport layer in Comparative Example 1 and Example 1. Figure 7 SEM images of the perovskite light-absorbing layers of Comparative Example 1 and Example 1 after 200 hours of irradiation; Figure 8 A comparison of the intensity ratio changes of the PbI2 and perovskite (100) diffraction peaks during the stability test of the perovskite light-absorbing layer in Comparative Example 1 and Example 1. Figure 9 The image shows a comparison of the light reflectance spectra of the semi-transparent perovskite solar cells prepared in Example 1 and Comparative Example 1. Figure 10 The image shows a comparison of the light transmittance spectra of the semi-transparent perovskite solar cells prepared in Example 1 and Comparative Example 1. Figure 11 The JV curves of the semi-transparent perovskite solar cell devices prepared in Example 1 and Comparative Example 1 are obtained by actual measurement. Figure 12 The image shows a comparison of the EQE spectra of the semi-transparent perovskite solar cell devices prepared in Example 1 and Comparative Example 1 during stability testing. Figure 13 The figures show the operational stability test results of the semi-transparent perovskite solar cell devices prepared in Example 1 and Comparative Example 1. Detailed Implementation

[0023] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0024] Example 1 A hole transport layer with uniform interface distribution is prepared by the following method: 1) Pre-treatment of ITO glass substrate (1cm×1cm): The ITO glass substrate was ultrasonically cleaned sequentially with neutral detergent, deionized water and anhydrous ethanol for 15 minutes each time. After cleaning, it was dried with high-purity nitrogen and then placed in a UV ozone cleaner for 15 minutes to obtain the pre-treated ITO substrate. 2) VO2 is deposited on the surface of the ITO glass substrate pretreated in step 1) using magnetron sputtering. x The specific deposition process conditions are as follows: The pretreated ITO glass substrate is placed on the surface of the deposition chamber stage; the target is a high-purity V metal target (99.95 wt%); the distance between the target and the stage is 70 mm; the working gas is a mixture of Ar and O2 at a volume ratio of 100:5; and the deposition chamber is evacuated to a vacuum level below 3.75 × 10⁻⁶. -5 Torr was used to set the substrate temperature to 200℃, the sputtering power to 65W, and the sputtering time to 120min, to obtain VO on the surface of an ITO glass substrate. x Layer (approximately 50nm thick); 3) Using magnetron sputtering in VO x NiO continues to be deposited on the surface of the layer x The specific deposition process conditions were as follows: the target material was a high-purity Ni target; the distance between the target material and the stage was 50 mm; the working gas was a mixture of Ar and O2 at a volume ratio of 100:5; and the deposition chamber was evacuated to a vacuum level below 3.75 × 10⁻⁶. -5 Torr was used to set the sputtering power to 200W and the sputtering time to 150min to obtain ITO / VO x -NiO x Composite interface (NiO) x (thickness approximately 20nm) 4) Dissolve 4PADCB in ethanol to obtain a crude solution. Draw the crude solution into a syringe and filter it under pressure through a 0.3µm needle filter to remove SAM solution and agglomerates, obtaining a 0.5mg / mL 4PADCB solution. Add 80μL of the 4PADCB solution dropwise to the ITO / VO2 obtained in step 3). x / NiO x The composite interface surface was uniformly spin-coated at a spin speed of 3000 rpm for 30 seconds, followed by annealing at 100°C under vacuum for 10 minutes to obtain VO on the ITO glass substrate surface. x Regulating the hole transport layer of the composite interface.

[0025] The fabrication method of a semi-transparent perovskite solar cell based on the above-mentioned hole transport layer further includes the following steps: 5) 61.83 mg cesium iodide (CsI), 199.83 mg formamidine iodide (FAI), 154.14 mg lead bromide (PbBr2), and 451.79 mg lead iodide (PbI2) were prepared according to the chemical structural formula Cs. 0.17 FA 0.83 Pb(I 0.80 Br 0.20 Mix the components in the ratio of 3 and dissolve them in 1 mL of DMF / DMSO mixed solvent (volume ratio DMF:DMSO=3:1). Shake at a frequency of 200 times / min for 3 hours to obtain a perovskite precursor solution. Take 100 μL of the perovskite precursor solution and drop it onto the surface of the hole transport layer. Spin coat it evenly at a speed of 5000 rpm for 30 seconds. 8 seconds before the end of the spin coating, add 180-200 μL of antisolvent EA at a uniform rate. Then anneal it at 100℃ for 30 minutes under vacuum to obtain the perovskite light-absorbing layer. 6) Transfer the ITO glass substrate to a vacuum evaporator, first deposit 30nm C60 on the surface of the perovskite light-absorbing layer, and then use an atomic layer deposition device to deposit 20nm SnO on the C60. x Thus, an electron transport layer is obtained; 7) Transfer the ITO glass substrate to an RF sputtering device and RF sputter 100nm IZO on the electron transport layer surface. Then, use a thermal evaporation device to deposit a 300nm silver electrode on the IZO to obtain a semi-transparent perovskite solar cell.

[0026] Comparative Example 1 A hole transport layer, which differs from Example 1 in that it does not contain VO x (Step 2 is omitted during the preparation process of the layer).

[0027] A semi-transparent perovskite solar cell was prepared using the same method as in Example 1.

[0028] X-ray photoelectron spectroscopy was used to test the hole transport layers prepared in this comparative example and Example 1. Before testing, the samples were etched and thinned using an argon ion gun with an etching spot size of 1.5 mm and an etching voltage of 3000 eV. Figure 1 The figure shows the O 1s energy spectrum of the hole transport layer prepared in Comparative Example 1 and Example 1. The relative surface hydroxyl density was obtained based on the peak area ratio of adsorbed hydroxyl species to lattice oxygen components. The higher the surface hydroxyl density, the more favorable it is for the chemisorption of SAM. The results show that compared with the ITO / NiO hole transport layer of Comparative Example 1, the surface hydroxyl density is higher. x (91.5%), ITO / VO hole transport layer in Example 1 x -NiO xThe relative surface hydroxyl density of the composite interface reaches 117.5%, which effectively compensates for the hydroxyl site defects caused by incomplete coverage and insufficient density of the NiOx layer.

[0029] Figure 2 ITO / VO for the hole transport layer in Example 1 x -NiO x Energy dispersive spectroscopy (EDS) of Ni and V elements at the composite interface, V2P 3 / 2 The spectrum can be fitted to V 5+ (~517.0 eV) and V 4+ Two components (~516.0 eV), where V 5+ Dominance indicates VO x The layer is mainly composed of high-valence vanadium oxides. Meanwhile, Ni₂P… 3 / 2 The spectrum is clearly discernible, Ni 2+ Main peak, distinct satellite peaks, VO x With NiO x Signals coexist, and V 5+ dominant VO x The layer has high surface energy, and the results confirm that VO x The layer can effectively fill NiO x Pinholes and voids in the sputtered thin film form VO x -NiO x The interwoven composite interface confirms the simultaneous presence of nickel and vanadium on the surface of the hole transport layer film prepared in Example 1, demonstrating the presence of inserted VO x The layer was filled with NiO x Incomplete film coverage creates voids, which then form VO on the surface. x -NiO x Composite layer.

[0030] Figure 3 The p2p energy spectrum of the hole transport layer prepared in Comparative Example 1 and Example 1 is shown. The p2p signal represents the terminal phosphate group of the SAM molecule. The SAM molecule is anchored to the surface of the hole transport layer through the phosphate group. Therefore, the intensity of the p2p signal directly reflects the anchoring amount of SAM. The p2p signal intensity of Example 1 is about 25% higher than that of Comparative Example 1, which further proves that there are more SAM molecules adsorbed on the surface of Example 1, and its SAM coverage is higher and denser.

[0031] The surface potential distribution of the hole transport layers prepared in Comparative Example 1 and Example 1 was tested using a Cypher S atomic force microscope. Figure 4The left image shows the surface potential distribution and fluctuation curve of the hole transport layer prepared in Comparative Example 1, while the right image shows the surface potential distribution and fluctuation curve of the hole transport layer prepared in Example 1. The results show that the hole transport layer prepared in Example 1 exhibits a more uniform local surface potential distribution and minimal fluctuation after SAM deposition. This indicates that the SAM molecules are arranged in an ordered manner and continuously cover the surface, demonstrating excellent physical homogeneity.

[0032] Figure 5 The images show scanning electron microscope (SEM) images of the perovskite light-absorbing layers further prepared on the hole transport layer in Comparative Example 1 and Example 1. By comparison, the perovskite crystals in the perovskite light-absorbing layer of Example 1 are more uniform, indicating that VO x The introduction of the layer significantly improved NiO x Physicochemical properties of thin films and the uniformity of self-assembled monolayers on their surfaces.

[0033] Figure 6 The XRD patterns of the perovskite light-absorbing layers further prepared on the hole transport layer in Comparative Example 1 and Example 1 are shown. x After layer modification, the full width at half maximum (FWHM) of the perovskite (100) diffraction peak decreased from 0.152° in Comparative Example 1 to 0.139° in Example 1, indicating that the crystallinity of the perovskite absorbing layer prepared in Example 1 was significantly improved and the defect density was reduced. These conclusions are consistent with... Figure 5 The observations from the SEM images are consistent.

[0034] In wide-bandgap perovskite solar cells (WBG-PSCs), photoinduced halide phase separation is one of the key mechanisms leading to performance degradation. This process not only significantly reduces key parameters such as open-circuit voltage (Voc) but also severely impairs the long-term operational stability of the device. To evaluate the stability of the materials under extreme conditions, the perovskite light-absorbing layers further prepared on the hole transport layer in Comparative Example 1 and Example 1 were placed on a heating stage at 85°C and subjected to simulated sunlight (irradiance 1000 W / m²) according to the AM1.5G standard. 2 (i.e., 1 sun) continuous irradiation for 200 hours, Figure 7 The images show SEM images of the perovskite absorber layers of Comparative Example 1 and Example 1 after 200 hours of irradiation. The perovskite absorber layer of Comparative Example 1 showed severe decomposition after 200 hours of irradiation, while the perovskite absorber layer of Example 1 showed less degradation. Further XRD analysis of the structural changes of the perovskite (100) crystal plane (14.2°) and the PbI2 (100) crystal plane (12.8°) was performed, and the results are compared as follows. Figure 8As shown (Comparative Example - fresh indicates the perovskite absorbing layer of Comparative Example 1 before testing, Comparative Example - Aged indicates the perovskite absorbing layer of Comparative Example 1 after 200 hours of irradiation, Example - fresh indicates the perovskite absorbing layer of Example 1 before testing, Example - Aged indicates the perovskite absorbing layer of Example 1 after 200 hours of irradiation), the intensity ratio of the PbI2 to perovskite (100) diffraction peaks in Comparative Example 1 was consistently higher than that in Example 1, increasing from 0.09 to 1.345, while in Example 1 it increased from 0.053 to 0.297. The significant increase in the peak intensity ratio of the thin film in Comparative Example 1 indicates a more severe degree of decomposition, a conclusion consistent with... Figure 7 The SEM observations were completely consistent.

[0035] The performance test results of the semi-transparent perovskite solar cells prepared in Example 1 and Comparative Example 1 are shown in Table 1.

[0036] Table 1

[0037] Table 1 J sc Represents short-circuit current. V oc FF represents open-circuit voltage, FF represents fill factor, and PCE represents photoelectric conversion efficiency.

[0038] Figure 9 This is a comparison of the light reflectance spectra of the semi-transparent perovskite solar cells prepared in Example 1 and Comparative Example 1. The light reflectance of the solar cell in Comparative Example 1 is generally higher across the entire wavelength range, while the light reflectance of the solar cell in Example 1 is significantly lower across the entire wavelength range, indicating that VOCs... x The introduction of [something] reduces the light reflectivity of solar cell devices.

[0039] Figure 10 The image shows a comparison of the light transmittance spectra of the semi-transparent perovskite solar cells prepared in Example 1 and Comparative Example 1. It can be seen that the solar cell device of Example 1 has a higher overall light transmittance across the entire wavelength range, while the device of Comparative Example 1 has a lower overall light transmittance across the entire wavelength range, indicating that VOCs... x The introduction of [something] improves the light transmittance of the device.

[0040] Figure 11 The JV curves of the semi-transparent perovskite solar cell devices prepared in Example 1 and Comparative Example 1 are obtained from actual measurements. Combined with Table 1, it can be seen that VO... x The introduction of VO improves the short-circuit current, open-circuit voltage, and fill factor of the device to a certain extent. (Comparative Example 1 without VO introduction...) x The efficiency of the perovskite solar cell device in this group is 19.27%. Example 1 introduces VO xIt later increased to 20.64%.

[0041] To further test the stability of the solar cell devices at the maximum power point, the semi-transparent perovskite solar cell devices prepared in Example 1 and Comparative Example 1 were placed in open ambient air. Using a solar simulator light source matched with AM1.5G, the EQE spectrum of the devices was measured using a solar cell quantum efficiency measurement system. The results are as follows: Figure 12 As shown in the curve analysis, the quantum efficiency (EQE) of Example 1 is significantly higher than that of Comparative Example 1 in the 400-800nm ​​wavelength range. This is because the integral of the EQE curve corresponds to the short-circuit current density of the corresponding perovskite solar cell. J sc Therefore, the curve supports this. Figure 11 The test results of Example 1, in which the short-circuit current density is higher than that of Comparative Example 1, verify the rationality and authenticity of the JV curve and intuitively demonstrate the improvement of the device's optoelectronic performance.

[0042] The MPPT long-term stability test of the semi-transparent perovskite solar cell devices prepared in Comparative Example 1 and Example 1 was conducted. MPPT measures the efficiency degradation of a device under continuous illumination while operating at its maximum power output. The test system continuously monitors the current-voltage output of the device, and the operating voltage is adjusted in real time using an algorithm (such as the perturbation-observation method) to maintain the device at its maximum power point. In the MPPT test, the encapsulated device was continuously exposed to light in open air under simulated AM1.5G single-day illumination conditions. The test system consisted of an LED solar simulator, an MPPT tracker, and a data acquisition system. Before the test, the light intensity was calibrated to 100 mW / cm² using a standard silicon reference cell. 2 (AM1.5G), the test temperature was controlled at 25±2℃. Test results are shown below. Figure 13 Experimental results show that the device in Example 1 exhibits excellent operational stability, maintaining 98% of its initial photoelectric conversion efficiency after 1472 hours of continuous operation. In contrast, the photoelectric conversion efficiency of the device in Comparative Example 1 dropped to 80% of its initial value after only 450 hours.

[0043] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A hole transport layer with uniform interface distribution, characterized in that, It includes: A vanadium oxide layer is disposed on the upper surface of an ITO glass substrate; A nickel oxide layer is disposed on the upper surface of the vanadium oxide layer; A self-assembled monolayer is disposed on the upper surface of the nickel oxide layer.

2. The hole transport layer with uniform interface distribution according to claim 1, characterized in that, The thickness of the vanadium oxide layer is 2-50 nm.

3. The hole transport layer with uniform interface distribution according to claim 1, characterized in that, The thickness of the nickel oxide layer is 20-50 nm.

4. The hole transport layer with uniform interface distribution according to claim 1, characterized in that, The self-assembled monolayer is (4-(7H-dibenzo[c,g]carbazole-7-yl)butylphosphonic acid.

5. A method for preparing a hole transport layer with uniform interface distribution as described in any one of claims 1-4, characterized in that, The specific steps are as follows: 1) A vanadium oxide layer and a nickel oxide layer are sequentially deposited on the surface of a pretreated ITO glass substrate to obtain a composite interface; 2) Dissolve SAM in an organic solvent to obtain a crude solution, filter to remove agglomerates, and obtain a SAM solution. Coat the obtained SAM solution onto the composite interface surface obtained in step 1), and anneal it to obtain a hole transport layer with uniform interface distribution on the surface of the ITO glass substrate.

6. The method for preparing a hole transport layer with uniform interface distribution according to claim 5, characterized in that, Step 1) The method for pre-treatment of ITO glass substrate is as follows: The ITO glass substrate is ultrasonically cleaned sequentially with neutral detergent, deionized water and anhydrous ethanol for 5-15 minutes each time. After cleaning, it is dried with high-purity nitrogen and then placed in a UV ozone cleaner for 5-15 minutes. Step 1) The method for depositing vanadium oxide layer and nickel oxide layer is magnetron sputtering or chemical vapor deposition.

7. The method for preparing a hole transport layer with uniform interface distribution according to claim 5, characterized in that, Step 2) The organic solvent is ethanol; Step 2) The concentration of the SAM solution is 0.3-0.7 mg / mL; Step 2) The method for removing aggregates by filtration is as follows: first, draw up the crude solution with a syringe, and then filter out the SAM solution under pressure using a needle filter with a pore size of 0.3 µm; Step 2) The method for coating the SAM solution onto the composite interface surface is as follows: spin coating is used, and the amount of SAM solution applied to the composite interface surface is 40-80 μL / cm. 2 The spin coating speed is 3000-6000 rpm and the spin coating time is 30-40s; Step 2) Annealing process conditions are: heating at 100-150℃ for 10-15min.

8. A semi-transparent perovskite solar cell containing a hole transport layer with a uniform interface distribution as described in any one of claims 1-4.

9. The semi-transparent perovskite solar cell according to claim 9, characterized in that, The semi-transparent perovskite solar cell comprises an ITO glass substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and a transparent electrode, which are stacked sequentially.

10. A method for preparing a semi-transparent perovskite solar cell according to claim 8 or 9, characterized in that, The process includes the following steps: after preparing a hole transport layer on the surface of an ITO glass substrate, a perovskite light-absorbing layer, an electron transport layer, and a transparent electrode are prepared sequentially to obtain a semi-transparent perovskite solar cell.

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