Trimethoprim hydrochloride modified inverted inorganic perovskite solar cell and preparation thereof

Abstract

The application discloses an inverted inorganic perovskite solar cell based on an interface modification layer of trimethoprim hydrochloride and a preparation method and application thereof, and belongs to the technical field of solar cells. The inverted inorganic perovskite solar cell comprises, from bottom to top, FTO conductive glass, a hole transport layer, a self-assembled small molecule layer, an active layer, an electron transport layer, a hole blocking layer and a metal electrode. The application uses a trimethoprim hydrochloride film as an interface modification layer between a perovskite layer and an electron transport layer, is applied to an inorganic perovskite solar cell, reduces the generation of interface defects, inhibits the non-radiative recombination of carriers, improves the interface energy level arrangement, promotes the extraction and transport of carriers, and is helpful to improving the photoelectric conversion efficiency of the inorganic perovskite solar cell. The application provides an effective method for the commercial development of low-cost and high-efficiency inorganic perovskite solar cells.

Description

Technical Field

[0001] This invention belongs to the field of solar cell technology, specifically relating to an inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer, its preparation method, and its application. Background Technology

[0002] As human demand for energy increases, solar energy, as a crucial component of new energy sources, has garnered widespread attention. Solar cells are one of the main methods of utilizing solar energy, and perovskite solar cells (PSCs) are among the leading third-generation solar cells, experiencing rapid development and gradually achieving commercialization. However, in the actual fabrication and operation of solar cells, high temperatures often affect the device's performance, leading to degradation. In the face of these adverse conditions, inorganic perovskites have shown significant application potential. For a long time, inorganic perovskite solar cells have primarily used a nip structure. However, this structure typically employs Spiro-OMeTAD as the hole transport material and TiO2 as the electron transport material. Spiro-OMeTAD usually requires the use of highly hygroscopic lithium salts, while TiO2 exhibits photocatalytic activity, which is detrimental to the stability of inorganic perovskites (Adv. Energy Mater. 2024, 14, 2303997; Phys. Chem. Solids, 2025 196, 112324). In contrast, trans-inorganic PSCs use NiO x and PC 61 BM serves as a charge transport layer, which effectively overcomes the limitations of the formal structure.

[0003] Although inverted inorganic perovskite solar cells have shown great development prospects, there are still some problems. In the preparation process of inorganic perovskite thin films, relatively high preparation temperatures are usually required, leading to rapid solvent evaporation, which easily causes the surface of the perovskite thin films to be rough, generating many interfacial defects and damaging the efficiency of perovskite solar cells. At the same time, the mismatched energy levels between the perovskite layer and the electron transport layer affect the transport of charge carriers. In addition, in a relatively humid environment, the black-phase perovskite phase of inorganic perovskite will turn into a yellow non-perovskite phase, seriously affecting the lifespan of inorganic perovskite solar cells. However, in current preparation methods, there are limited ways to solve these problems simultaneously, which affects the improvement of the performance of inorganic perovskite solar cells (Small, 2024, 20:2407826; Chem. Eng. J. 2024, 500:157370; Solar RRL 2025, 0, e202500695). Therefore, it is necessary to develop an effective solution that can simultaneously reduce the surface roughness of inorganic perovskite, passivate surface defects, and improve humidity stability, which is of great significance for the development of low-cost and high-efficiency all-inorganic perovskite solar cells. Summary of the Invention

[0004] In view of the above technical problems, the present invention provides an inverted inorganic perovskite solar cell based on a trimethoprim hydrochloride interface modification layer and a preparation method thereof. By introducing this interface modification layer, it aims to improve the crystallization quality of perovskite thin films, reduce the interfacial defect density, and optimize the energy level arrangement, thereby significantly improving the photoelectric conversion efficiency and air stability of the solar cell.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions:

[0006] In the first aspect, the present invention provides an inverted inorganic perovskite solar cell based on a trimethoprim hydrochloride interface modification layer, which successively includes, from bottom to top: an anode layer, a hole transport layer, a self-assembled small molecule layer, an active layer, an interface modification layer, an electron transport layer, a hole blocking layer, and a metal electrode layer; wherein, the interface modification layer is a trimethoprim hydrochloride layer.

[0007] Further, the hole transport layer is a nickel oxide layer with a thickness of 10 - 50 nm.

[0008] Further, the self-assembled small molecule layer is any one of Meo-2PACz, 2PACz, Meo-4PACz, and 4PACz small molecule layers, and its thickness is 0.5 - 10 nm.

[0009] Further, the active layer is a CsPbI 3-x Br x inorganic perovskite active layer, where 0 < x < 2, and its thickness is 200 - 800 nm.

[0010] Furthermore, the thickness of the interface modification layer is 1~10 nm.

[0011] Furthermore, the electron transport layer is (6,6)-phenyl-C61-butyrate methyl ester (PC). 61 BM layer and C 60 The thickness of any one or two layers in the layer is 5~60 nm.

[0012] Furthermore, the hole-blocking layer is a 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) layer with a thickness of 1~10 nm.

[0013] Furthermore, the metal electrode layer is any one of gold (Au), silver (Ag), copper (Cu) and aluminum (Al); its thickness is 50~150 nm.

[0014] Furthermore, the hole transport layer is prepared by any one of the following processes: spin coating, scraping coating, spray coating, etc.

[0015] Furthermore, the self-assembled small molecule layer is obtained through any one of the processes such as spin coating, blade coating, or spray coating.

[0016] Furthermore, the active layer is obtained by any one of the following processes: spin coating, evaporation, blade coating, spray coating, etc.

[0017] Furthermore, the interface modification layer is obtained by any one of the processes such as spin coating, scraping coating, or spraying.

[0018] Furthermore, the electron transport layer is prepared by any one of the following processes: spin coating, evaporation, blade coating, spray coating, etc.

[0019] Furthermore, the hole-blocking layer is obtained by any one of the following processes: spin coating, evaporation, scraping, or spraying.

[0020] Furthermore, the metal electrode is prepared by any one of the following processes: thermal evaporation, atomic deposition, etc.

[0021] Secondly, the present invention provides a method for preparing an inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer, comprising the following steps:

[0022] Step 1: Fabricate a hole transport layer on the substrate;

[0023] Step 2: Prepare a self-assembled small molecule layer on the surface of the hole transport layer;

[0024] Step 3: Perform surface post-treatment with an alcohol solvent on the self-assembled small molecule layer;

[0025] Step 4: Prepare an inorganic perovskite active layer on the post-treated self-assembled small molecule layer;

[0026] Step 5: Prepare a dimethoprim hydrochloride interface modification layer on the surface of the active layer;

[0027] Step 6: Prepare an electron transport layer on the surface of the interface modification layer;

[0028] Step 7: Prepare a hole blocking layer on the surface of the electron transport layer;

[0029] Step 8: Prepare a metal electrode layer on the surface of the hole blocking layer.

[0030] Further, in step one, the substrate is fluorine-doped tin oxide conductive glass, and the hole transport layer is a nickel oxide layer; the hole transport layer precursor solution is a deionized aqueous solution of nickel oxide with a concentration of 10~50 mg / mL; the spin coating method is static spin coating in air, with a rotation speed of 3000~6000 rpm and a spin coating time of 20~60 s; after spin coating, it is annealed at 100~180 ℃ for 10~30 min; then it is treated in an ultraviolet ozone environment for 1~10 min before use.

[0031] Further, step two includes: first, preparing a Meo-2PACz self-packing small molecule precursor solution, an ethanol solution with a concentration of 0.1~3 mg / mL, and dissolving it by thorough shaking to obtain the Meo-2PACz precursor solution; in a nitrogen glove box or air environment with water and oxygen contents both less than 0.01 parts per million, nitrogen purity of 99.999%, and pressure of 3±2 mbar, using a pipette to drop 50~100 μL of PTAA solution onto the nickel oxide hole transport layer, and spin-coating at a speed of 1000~8000 rpm for 20~40 s; annealing the spin-coated Meo-2PACz film on a hot stage at 50~150 ℃ for 2~20 min to prepare a stable Meo-2PACz film.

[0032] Furthermore, in step three, 50–500 mL of alcohol solvents with similar polarities, such as methanol, ethanol, isopropanol, n-propanol, and ethylene glycol, are used for surface post-treatment of the self-assembled small molecules via dynamic spin coating at a spin coating speed of 1000–8000 rpm for 20–40 s. The treated self-assembled small molecule layer is then annealed on a hot plate at 50–150 °C for 2–20 min to complete the post-treatment of the self-assembled small molecule layer.

[0033] Furthermore, as described in step four, CsPbI 3-x Br x Perovskite films were prepared by dissolving cesium iodide (CsI), dimethylamine lead iodide (DMAPbI3), and lead bromide (PbBr2) in a molar ratio of 1:0.95±0.6:0.05±0.6 in a mixed solvent of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) in any proportion to form a 0.5–1.5 mol / L inorganic perovskite precursor solution. Then, 40–100 μL of the perovskite precursor solution was dropped onto the self-assembled small molecular layer and spin-coated at 500–2000 rpm for 3–10 s, followed by increasing the spin speed to 3000–5000 rpm for 20–50 s. After spin-coating, the film was pre-annealed at 70–90 °C for 2–5 min, and then annealed at 180–220 °C for 5–20 min to obtain stable CsPbI3 films. 3-x Br x Inorganic perovskite thin films.

[0034] Further, in step five, the interface modification layer is prepared by dissolving dimethoprim hydrochloride in alcohol solvents with similar polarities such as methanol, ethanol, isopropanol, n-propanol, and ethylene glycol to form an interface modification layer solution with a concentration of 0.1–5 mg / mL. Then, 40–100 μL of the interface modification layer solution is dropped onto the surface of the perovskite film and spin-coated at a speed of 2000–8000 rpm for 20–50 s to form the interface modification layer.

[0035] Furthermore, the electron transport layer is a PC. 61 When working at the BM layer, step six includes transferring the PC... 61 BM was dissolved in chlorobenzene to prepare an electron transport layer precursor solution with a concentration of 10-40 mg / mL; then 40-100 μL of the electron transport layer precursor solution was dropped onto the surface of the perovskite film and spin-coated at a speed of 2000-8000 rpm for 20-50 s to form PC. 61 BM electron transport layer.

[0036] Furthermore, the electron transport layer in question is C. 60 When layering, step six includes, by C 60 The powder was placed in a crucible and heated under a vacuum of 10... -4 ~10 -5 The C20 is heated and evaporated in a vacuum evaporation chamber at a rate of 0.02~0.05 nm / s. 60 Uniformly covering the surface of the perovskite film, forming C 60 Electron transport layer.

[0037] Furthermore, when the hole-blocking layer is a BCP layer, step seven includes preparing an electron transport layer precursor solution with a concentration of 0.1~2 mg / mL by dissolving BCP in isopropanol solvent; then taking 40~100 μL of the electron transport layer precursor solution as droplets on the surface of the perovskite film and spin-coating it at a rotation speed of 3000~8000 rpm for 20~50 s to form a BCP hole-blocking layer.

[0038] In step four, the inorganic perovskite active layer is CsPbI. 3-x Br x The layer was prepared by spin-coating a perovskite precursor solution and annealing. The perovskite precursor solution was prepared by dissolving cesium iodide, dimethylamine lead iodide, and lead bromide in a molar ratio of 1:(0.95±0.6):(0.05±0.6) in a mixed solvent of N,N-dimethylformamide and dimethyl sulfoxide, with a concentration of 0.5~1.5 mol / L.

[0039] Thirdly, the present invention provides the application of dimethoxybenzyl hydrochloride as an interface modification material in improving the performance of inverted inorganic perovskite solar cells. The dimethoxybenzyl hydrochloride is prepared into a thin film and disposed between the perovskite active layer and the electron transport layer of the solar cell.

[0040] Using dimethoxybenzyl hydrochloride as an interface modification layer, the performance of inorganic perovskite solar cells is improved in the following ways:

[0041] 1) Surface modification of perovskite films using dimethoxybenzyl chloride hydrochloride improves the crystallinity of perovskite films;

[0042] 2) The dimethoxybenzyl chloride surface modification layer effectively reduces the surface roughness of the perovskite film, improves the interfacial contact between the perovskite film and the electron transport layer, and passivates interfacial defects.

[0043] 3) Optimize the energy level matching between the perovskite and the hole transport layer to improve the electron extraction efficiency at the perovskite / electron transport layer interface.

[0044] 4) The strong coordination between the amine group in dimethoxybenzyl hydrochloride and the lead ion in the perovskite, as well as the hydrophobic functional group in dimethoxybenzyl, significantly improve the stability of inorganic perovskite solar cells.

[0045] Fourthly, the present invention provides a photovoltaic module or photovoltaic power generation system comprising the aforementioned inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer.

[0046] Compared with the prior art, the present invention has the following advantages:

[0047] This invention employs a low-cost dimethoxybenzidine hydrochloride interface modification layer to modify the interface between the active layer and the electron transport layer. On one hand, this effectively improves the crystallinity of the perovskite film, reduces surface roughness, improves interfacial contact, and optimizes the energy level arrangement of the interface. This promotes electron extraction and transport between the active layer and the electron transport layer, suppresses nonradiative recombination of charge carriers, and thus enhances the photovoltaic performance of the inorganic perovskite solar cell. On the other hand, thanks to the improved crystallinity of the perovskite film and the influence of the hydrophobic groups in the dimethoxybenzidine hydrochloride, the moisture resistance of the inorganic perovskite film is effectively improved, and the stability of the device in air is also enhanced. This method provides an effective solution for the development of low-cost, high-efficiency, and stable inorganic perovskite solar cells. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the structure of an inverted inorganic perovskite solar cell provided in an embodiment of the present invention.

[0049] Figure 2 The images show a comparison of the scanning electron microscope morphology of perovskite films with and without the interface modification layer of this invention.

[0050] Figure 3 A comparison of the current-voltage characteristic curves of perovskite solar cells with and without the interface modification layer of this invention.

[0051] Figure 4 This is a comparison chart showing the efficiency and stability of perovskite solar cells with and without the interface modification layer of this invention in an air environment. Detailed Implementation

[0052] To gain a deeper understanding of this invention, we will provide a comprehensive and detailed description. However, this invention has various implementations and is not limited to the specific examples listed herein. These examples are presented to enhance a full understanding of the disclosure of this invention.

[0053] Example 1:

[0054] 10 mg of nickel oxide powder was dissolved in deionized water and stirred for 30 min to prepare a 10 mg / mL nickel oxide solution. 0.5 mg of 2PACz powder was dissolved in ethanol and stirred for 30 min to prepare a 0.5 mg / mL self-contained small molecule solution. 207.8 mg of CsI, 456.5 mg of DMAPbI3, and 29.4 mg of PbBr2 powder were dissolved in a 4:1 (v / v) mixed solvent of DMF and DMSO and stirred under nitrogen atmosphere for 4 h to prepare a 0.8 M CsPbI3 solution. 2.7 Br 0.3Perovskite solution; Weigh 0.5 mg of dimethoprim hydrochloride powder and dissolve it in isopropanol solvent, stir for 30 min, and prepare a dimethoprim hydrochloride solution with a concentration of 0.5 mg / mL; Weigh 20 mg of PCBM powder and dissolve it in chlorobenzene solvent, stir for 30 min, and prepare a PCBM solution with a concentration of 20 mg / mL; Weigh 0.5 mg of BCP powder and dissolve it in isopropanol solvent, stir for 30 min, and prepare a BCP solution with a concentration of 0.5 mg / mL.

[0055] 1) 50 μL of nickel oxide solution was statically spin-coated onto a clean FTO glass at a spin speed of 4000 rpm for 30 s. Then, it was annealed at 150℃ for 10 min to prepare a nickel oxide thin film, forming a hole transport layer.

[0056] 2) 100 μL of small molecule solution was statically spin-coated onto the surface of the prepared nickel oxide hole transport layer at a spin speed of 3000 rpm for 30 s. After spin-coating, the layer was annealed at 100 °C for 10 min to form a self-assembled small molecule layer.

[0057] 3) Static spin-coating 200 μL of ethanol solution onto the surface of the prepared self-assembled small molecule layer at a spin speed of 5000 rpm for 30 s. After spin-coating, anneal at 100 °C for 3 min to complete the surface treatment of the self-assembled small molecule layer.

[0058] 4) Add 50 μL of the prepared CsPbI 2.7 Br 0.3 The perovskite solution was statically spin-coated onto the surface of the prepared self-assembled small molecule layer. The spin speed was initially set to 1000 rpm and the spin coating time was 5 s. Then, the spin speed was increased to 4000 rpm and the spin coating time was increased to 35 s. After spin coating, the perovskite film was pre-annealed at 70℃ for 1 min and then annealed at 200℃ for 15 min to form a perovskite film as the active layer.

[0059] 5) Static spin-coating 50 μL of the prepared dimethoprim hydrochloride solution onto the surface of the active layer at a speed of 4000 rpm for 30 s; after spin-coating, anneal at 100℃ for 5 min to form an interface trimming layer.

[0060] 6) Add 50 μL of the prepared PC 61 BM solution was statically spin-coated onto the surface of the prepared perovskite film at a rotation speed of 4000 rpm for 30 s to form PC. 61 BM thin film, as an electron transport layer;

[0061] 7) 30 μL of the prepared BCP solution was statically spin-coated onto the surface of the prepared perovskite film at a speed of 5000 rpm for 30 s to form a BCP film as a hole blocking layer.

[0062] 8) A 100 nm thick Ag film is deposited on the surface of the hole blocking layer obtained above as a cathode to complete the assembly of the inorganic perovskite solar cell.

[0063] Examples 2-3

[0064] The device fabrication steps were exactly the same as in Example 1, except that the concentrations of the interface modification layer solution used in step (5) were 0.2 mg / mL (Example 2) and 0.8 mg / mL (Example 3), respectively.

[0065] Comparative Example

[0066] Except for not preparing and using the dimethoprim hydrochloride interface modification layer (i.e., omitting step (5) in Example 1), the remaining steps are exactly the same as in Example 1.

[0067] Performance Testing and Results

[0068] The photovoltaic performance of the above-described embodiments and control examples was tested using a solar cell testing system (equipped with an AM 1.5G standard solar simulator), and the results are shown in the table below:

[0069] Table 1. Photovoltaic performance parameters of solar cells obtained by preparing dimethoprim hydrochloride interface modification layers from precursor solutions of different concentrations.

[0070]

[0071] Results Analysis

[0072] As shown in the table, after introducing the dimethoprim hydrochloride interface modification layer (Examples 1-3), the photovoltaic parameters (open-circuit voltage, short-circuit current, and fill factor) of all devices were better than those of the control example, and the photoelectric conversion efficiency was significantly improved, proving that the modification layer effectively improved the device performance.

[0073] Figure 2 The results showed that the modified perovskite film had larger, denser grains and a smoother surface, verifying its effect of improving crystal quality and reducing roughness.

[0074] Figure 3 The embodiment demonstrates that the device has higher current output and open-circuit voltage.

[0075] Figure 4(Stability tests) show that the device with the interface modification layer has a significantly slower efficiency decay rate than the control after being stored in an air environment for the same period of time, proving that its stability is significantly enhanced.

[0076] In summary, this invention, by introducing dimethoxybenzyl chloride hydrochloride as an interface modification layer, achieves a synergistic improvement in the efficiency and stability of inverted inorganic perovskite solar cells in a simple and low-cost manner, which has significant practical value and broad application prospects.

[0077] Contents not described in detail in this specification are prior art known to those skilled in the art. Although illustrative specific embodiments of the invention have been described above to facilitate understanding by those skilled in the art, it should be understood that the invention is not limited to the scope of the specific embodiments. Various modifications are readily apparent to those skilled in the art as long as they fall within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of this invention are protected.

Claims

1. An inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer, characterized in that, From bottom to top, they include: The layers consist of an anode layer, a hole transport layer, a self-assembled small molecule layer, an active layer, an interface modification layer, an electron transport layer, a hole blocking layer, and a metal electrode layer. The interface modification layer is a dimethoxybenzyl chloride hydrochloride layer.

2. The inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer according to claim 1, characterized in that, The hole transport layer is a nickel oxide layer with a thickness of 10~50 nm; The self-assembled small molecular layer is any one of Meo-2PACz, 2PACz, Meo-4PACz and 4PACz small molecular layers, and its thickness is 0.5~10 nm; The active layer is CsPbI 3-x Br x inorganic perovskite active layer, where 0 < x < 2 and its thickness is 200 - 800 nm; The thickness of the interface modification layer is 1~10 nm; The electron transport layer is a (6,6)-phenyl-C61-butyrate methyl ester layer and a C… 60 The thickness of any one or two layers in the layer is 5~60 nm; The hole-blocking layer is a 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline layer with a thickness of 1~10 nm. The metal electrode layer is any one of gold, silver, copper and aluminum; its thickness is 50~150 nm.

3. The inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer according to claim 1, characterized in that, The interface modification layer is obtained by spin coating, scraping coating or spraying process.

4. A method for preparing an inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer according to any one of claims 1 to 3, characterized in that, Includes the following steps: Step 1: Fabricate a hole transport layer on the substrate; Step 2: Prepare a self-assembled small molecule layer on the surface of the hole transport layer; Step 3: Perform surface post-treatment with an alcohol solvent on the self-assembled small molecule layer; Step 4: Prepare an inorganic perovskite active layer on the post-treated self-assembled small molecule layer; Step 5: Prepare a dimethoprim hydrochloride interface modification layer on the surface of the active layer; Step 6: Prepare an electron transport layer on the surface of the interface modification layer; Step 7: Prepare a hole blocking layer on the surface of the electron transport layer; Step 8: Prepare a metal electrode layer on the surface of the hole blocking layer.

5. The method for preparing an inverted inorganic perovskite solar cell based on a dimethoxybenzyl chloride hydrochloride interface modification layer according to claim 4, characterized in that, A dimethoprim hydrochloride solution with a concentration of 0.1~5 mg / mL was spin-coated onto the surface of the active layer at a spin speed of 2000~8000 rpm for 20~50 seconds to form the interface modification layer.

6. The preparation method according to claim 5, characterized in that, The dimethoxybenzidine hydrochloride solution is prepared by dissolving dimethoxybenzidine hydrochloride in at least one solvent selected from methanol, ethanol, isopropanol, n-propanol, or ethylene glycol.

7. The preparation method according to claim 4, characterized in that, In step four, the inorganic perovskite active layer is CsPbI. 3-x Br x The layer is prepared by spin-coating a perovskite precursor solution and annealing. The perovskite precursor solution is prepared by dissolving cesium iodide, dimethylamine lead iodide and lead bromide in a molar ratio of 1:(0.95±0.6):(0.05±0.6) in a mixed solvent of N,N-dimethylformamide and dimethyl sulfoxide, with a concentration of 0.5~1.5 mol / L.

8. The application of dimethoxybenzyl hydrochloride as an interface modification material in improving the performance of inverted inorganic perovskite solar cells, characterized in that, The dimethoxybenzyl hydrochloride is prepared into a thin film and disposed between the perovskite active layer and the electron transport layer of the solar cell.

9. The application according to claim 8, characterized in that, The improved performance includes at least one of the following: improving the crystal quality of perovskite thin films, reducing the surface roughness of thin films, passivating interface defects, optimizing the interface energy level arrangement, improving carrier extraction and transport efficiency, suppressing nonradiative recombination of carriers, improving the photoelectric conversion efficiency of batteries, and improving the stability of batteries in air.

10. A photovoltaic module or photovoltaic power generation system, characterized in that, An inverted inorganic perovskite solar cell comprising at least one dimethoxybenzyl chloride hydrochloride interface modification layer as described in any one of claims 1 to 3.

Images