A method for preparing a flexible perovskite solar cell with improved self-repairing performance
Patent Information
- Application Number
- CN202310858390.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-12
- Publication Date
- 2026-09-22
- Estimated Expiration
- 2043-07-12
AI Technical Summary
虽然现在已经有研究者针对柔性钙钛矿太阳电池在多次循环弯曲后导致的光电转换效率下降等关键问题开展了研究，但是柔性钙钛矿太阳电池的自修复性能作为器件恢复的有效方法很少被报道
[0029]本发明提供了一种提升柔性钙钛矿太阳能电池的自修复能力的制备方法，通过在钙钛矿前驱体溶液中添加三氟苯磺酸酰胺(TFBSA)，使制备出的柔性钙钛矿太阳电池不仅拥有更高的光电转换效率，而且还显示出优异自修复能力。这对具有柔性钙钛矿太阳能电池的商业化应用提供了重要参考。
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Abstract
Description
Technical Field
[0001] This invention relates to a method for fabricating flexible perovskite solar cells with improved self-healing performance, and belongs to the field of energy technology. Background Technology
[0002] With the continuous development of society and the economy, traditional fossil fuels are gradually being depleted, and an energy crisis is imminent. Therefore, finding alternative new energy sources has become a primary issue for the development of countries worldwide. In the current field of new energy, solar energy possesses advantages such as abundant resources, wide distribution, no pollution, and sustainability. Furthermore, as a clean and natural energy source that is "inexhaustible," solar energy has become one of the most promising future energy sources. Against this backdrop, solar photovoltaic power generation technology has become a rapidly developing renewable energy technology in recent decades.
[0003] Perovskite solar cells, as an emerging photovoltaic technology, have attracted widespread attention due to their excellent photoelectric performance. To date, the highest conversion efficiency of perovskite solar cells has reached 25.7%, which is considered by many scholars to be a disruptive photovoltaic technology that will support the long-term development of the industry. With the upgrading of the perovskite solar cell industry chain, various types of flexible perovskite solar cells are beginning to emerge. Flexible perovskite solar cells have advantages such as light weight, flexibility, and low installation costs, and will have broad application prospects in BIPV (Building Integrated Photovoltaics), BAPV (Building Attached Photovoltaics), mobile objects, portable devices, and aerospace.
[0004] However, due to the inherent poor stability of perovskite materials, the photoelectric conversion efficiency of flexible perovskite solar cells is lower than that of rigid devices. The low cohesion of perovskite materials, coupled with the significant reduction in interfacial adhesion during heat treatment of flexible substrates, leads to poor mechanical adhesion between adjacent functional layers. Furthermore, since the mechanical flexibility of perovskite films is closely related to the bending radius and the number of bending cycles, mechanical durability and charge transfer have become prominent issues affecting the photoelectric conversion efficiency of flexible perovskite solar cells.
[0005] Currently, numerous strategies exist to improve the photoelectric conversion efficiency of flexible perovskite solar cells. These methods can avoid bending damage caused by stress concentration during bending, thereby improving crystal quality and flexibility. Although researchers have addressed key issues such as the decrease in photoelectric conversion efficiency after repeated bending cycles in flexible perovskite solar cells, the self-healing properties of flexible perovskite solar cells as an effective method for device recovery have been rarely reported. We added trifluorobenzenesulfonamide (TFBSA) to the perovskite precursor solution, which significantly improved the self-healing performance of the device. Summary of the Invention
[0006] The purpose of this invention is to develop a method for fabricating flexible perovskite solar cells with improved self-healing performance. This method involves introducing trifluorobenzenesulfonamide (TFBSA) into the perovskite precursor solution to anchor excess lead iodide (PbI2), suppressing its photodecomposition process and significantly improving carrier lifetime. Simultaneously, the addition of TFBSA significantly improves the vertical growth of perovskite crystals, resulting in a substantial enhancement of light absorption in the perovskite thin film. This improves the photoelectric conversion efficiency of the device and greatly enhances the self-healing performance of the flexible perovskite solar cell.
[0007] To achieve the above objectives, the present invention provides the following technical solution:
[0008] A method to fundamentally enhance the self-healing properties of flexible perovskite solar cells by adding trifluorobenzenesulfonamide (TFBSA). This includes the following steps:
[0009] 1. Pretreatment of experimental equipment
[0010] Before fabricating perovskite solar cell devices, all experimental equipment must be cleaned according to standard cleaning methods. The specific cleaning steps are as follows:
[0011] (1) First, put on sterile rubber gloves and take out the PEN / ITO flexible substrate. Then, take a clean beaker, pour in an appropriate amount of deionized water, and add an appropriate amount of detergent. Use a lint-free cloth soaked in the deionized water mixed with detergent to wipe the PEN / ITO substrate and remove the visible stains on the substrate surface.
[0012] (2) Then, the PEN / ITO flexible substrate was rinsed with deionized water and anhydrous ethanol in sequence and placed on the substrate holder. After all the substrates were rinsed, the substrate holder was placed in a beaker containing anhydrous ethanol and cleaned with an ultrasonic cleaner for 15 minutes. Then, the PEN / ITO flexible substrate was ultrasonically cleaned in the order of deionized water, isopropanol and anhydrous ethanol for 15 minutes. Finally, the substrate holder containing the cleaned PEN / ITO substrates was transferred to a clean beaker and placed in an oven to dry.
[0013] (3) After cleaning other utensils (such as glass bottles, stir bar, etc.) using standard cleaning methods, dry them in an oven and wrap them in aluminum foil for later use.
[0014] 2. Preparation of SnO2 electron transport layer using chemical bath method
[0015] Weigh out 1250 mg of urea, 275 mg of SnCl2·2H2O, and 1250 μL of HCl, dissolve them in 100 mL of deionized water, and then stir at room temperature for 30 min. Treat with PEN / ITO UV ozone for 15 min. After the substrate cools, place it in a prepared transparent chemical bath solution, and then place the beaker containing the substrate and chemical bath solution in an 85°C water bath for 5 h. After heating, ultrasonically clean the substrate with deionized water and isopropanol for 3 min each, and then anneal the substrate on an annealing station at 180°C for 1 h to obtain the SnO2 electron transport layer.
[0016] 3. Add TFBSA to the perovskite precursor solution and prepare a perovskite layer.
[0017] (1) First, a 0.9 mg / ml trifluorobenzenesulfonamide (TFBSA) solution was prepared by diluting 1500 μL of dimethylformamide (DMF) using the solution dilution method and stirred at 70°C for 12 h.
[0018] (2) Then, weigh 900 mg lead iodide (PbI2), 180 mg FAI, 18 mg MABr and 18 mg MACl in sequence and dissolve them in 3 ml isopropanol (IPA). Stir at 70 °C for 12 h to obtain a perovskite precursor solution; add TFBSA solution to the perovskite precursor solution.
[0019] (3) In a nitrogen atmosphere in a glove box, place the PEN / ITO substrate with the prepared electron transport layer on a spin coater, drop 80 μL of perovskite precursor solution onto the substrate, spin coat at 1500 rpm for 10 s, then spin coat at 5000 rpm for 30 s. At the 30th s of spin coating, quickly add chlorobenzene solution. Immediately after spin coating is completed, use tweezers to place the substrate on an annealing station at 100°C for 45 min.
[0020] 4. Preparation of hole transport layer
[0021] (1) Dissolve 72.3 mg of 2,2',7,7'-tetratetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene (spiro-OMeTAD) in 1 ml of chlorobenzene, then add 28.8 μL of tert-butylpyridine (tBP) and 17.5 μL of lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) acetonitrile solution (520 mg / ml). -1 (Li-TFSI / acetonitrile), after preparation, stir the solution at room temperature for 4 hours;
[0022] (2) After annealing, 55 μL of the above solution was dropped onto the substrate and spin-coated at 3000 rpm for 30 s to prepare the hole transport layer.
[0023] (3) After preparation, all substrates were placed in glass petri dishes lined with tin foil, and then the petri dishes were placed in a drying tank for 24 hours.
[0024] 5. Preparation of Ag Electrode
[0025] Ag electrodes were sputtered onto the device using a magnetron sputtering deposition method.
[0026] 6. Testing and Characterization
[0027] The fabricated device undergoes a series of tests, including JV curve testing, XRD testing, scanning electron microscopy testing, and thin film stability testing.
[0028] Compared with the prior art, the present invention has the following beneficial effects:
[0029] This invention provides a method for enhancing the self-healing capability of flexible perovskite solar cells. By adding trifluorobenzenesulfonamide (TFBSA) to the perovskite precursor solution, the prepared flexible perovskite solar cells not only possess higher photoelectric conversion efficiency but also exhibit excellent self-healing ability. This provides an important reference for the commercial application of flexible perovskite solar cells. Attached Figure Description
[0030] Appendix Figure 1 XRD patterns of the control group and perovskite-TFBSA films;
[0031] Appendix Figure 2 SEM images of the control group and perovskite-TFBSA films;
[0032] Appendix Figure 3 JV curves of flexible perovskite solar cells doped with optimal TFBSA and the control group.
[0033] Appendix Figure 4 Comparison of bending resistance performance of devices with a bending radius of 5mm and after 3000 bends;
[0034] Appendix Figure 5 The self-healing performance of the device in a dark environment after 3000 bending cycles;
[0035] Appendix Figure 6 Stability comparison chart of flexible perovskite solar cells in glove boxes; Detailed Implementation
[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0037] I. Testing of the Perovskite Active Layer in Flexible Perovskite Solar Cells
[0038] Appendix Figure 1The XRD patterns of the control group and the perovskite-TFBSA film are shown in the figure. As we can see from the figure, after adding 0.6 mg / ml TFBSA, the intensity of the (110) and (220) planes of the perovskite is significantly enhanced, while the intensity of the related peak of Pbl2 decreases, indicating that TFBSA has a significant promoting effect on the vertical growth of perovskite crystals.
[0039] Appendix Figure 2 These are SEM images of the control group and the perovskite-TFBSA film. SEM was used to observe the top grain morphology of the perovskite in both groups. The average grain size of the flexible perovskite film in the control group was only 285 nm, while the average grain size of the TFBSA-doped flexible perovskite film was 337 nm, which is more conducive to charge transfer. Therefore, the addition of TFBSA is more beneficial for improving crystal quality, promoting carrier migration, and reducing leakage current.
[0040] II. Photoelectric Performance Testing of Flexible Perovskite Solar Cells
[0041] We will test the flexible perovskite solar cells prepared through the above steps under standard conditions (1000 W / m). 2 The photoelectric performance of the battery was tested and analyzed using a solar irradiance (AM1.5, test temperature 25℃) with the aid of a solar simulator, an electrochemical workstation, a computer, and related software.
[0042] (1) JV curve test of perovskite solar cells
[0043] Appendix Figure 3 This is a comparison of the JV curves of flexible perovskite solar cells. Compared with the control group, we can see that the flexible perovskite solar cells prepared with optimal TFBSA doping exhibit better photoelectric conversion performance, with both short-circuit current and open-circuit voltage being quite good. The specific performance parameters of the cells are shown in the table below.
[0044] Standard film 21.74 1.099 68.80％ 16.44％ TFBSN 23.46 1.103 74.60％ 19.29％
[0045] As shown in the table above, our fabricated flexible perovskite solar cell exhibits superior photoelectric conversion efficiency compared to the control group. The modified device demonstrates higher open-circuit voltage and higher short-circuit current, while the photoelectric conversion efficiency is increased to 19.29%, resulting in a highly efficient and stable flexible solar cell device.
[0046] (2) Stability testing of flexible perovskite solar cells
[0047] Appendix Figure 4This figure shows the bending resistance and self-healing stability of flexible perovskite solar cells in the control and experimental groups with a bending radius of 5 mm. To verify the effect of bending on the flexibility of flexible perovskite solar cells, the photoelectric conversion efficiency of the flexible perovskite solar cells was measured after 3000 bending cycles with a curvature radius of 5 mm. As can be seen from the figure, after 3000 bending cycles, the flexible perovskite solar cell with added TFBSA exhibited excellent bending resistance, maintaining an initial conversion efficiency of 82%, while the control group only maintained 11%. This is because the introduction of TFBSA significantly improved the crystal strength of the perovskite crystals, thus allowing the perovskite film to bond tightly together during bending.
[0048] From the appendix Figure 5 It can be observed that after the device undergoes 3000 bending cycles and is then placed in a dark environment for 7 days, the PCE of the TFBSA-modified device recovers from 82% of its original value to 98%. After being placed in a dark glove box for 56 days, the improved device still maintains more than 90% of its initial efficiency, while the original device, placed in a dark glove box at room temperature for 7 days, only recovers from 11% to 19%, and drops to 12% after 56 days. This indicates that the self-healing performance of the device is greatly improved.
[0049] Appendix Figure 6 This is a comparison of the glove box stability of flexible perovskite solar cells. The graph shows that the TFBSA-doped FPSC retains 90% of its initial PCE after 1500 hours, while the PCE of the control group drops to 74%, indicating that the long-term stability of the TFBSA-modified FPSC is improved. This phenomenon directly reflects that TFBSA-modified flexible perovskite solar cells enhance the self-healing ability of perovskite, providing a new approach for the fabrication of commercial flexible perovskite solar cell devices.
[0050] For those skilled in the art, various modifications and improvements can be made to the present invention without departing from its principles, and these modifications and improvements also fall within the protection scope of the present invention.
Claims
1. A method for fabricating a flexible perovskite solar cell with improved self-healing performance, comprising: Cleaning of the ITO / PEN substrate at room temperature; A chemical bath solution was prepared by dissolving urea, SnCl2·2H2O, and HCl in deionized water. This solution was used to treat an ITO / PEN substrate with ultraviolet ozone. The PEN / ITO substrate was then placed in the chemical bath solution to prepare a SnO2 electron transport layer, followed by annealing. A trifluorobenzenesulfonamide solution was prepared by dissolving trifluorobenzenesulfonamide in dimethylformamide solution and heating with stirring. Lead iodide, FAI, MABr, and MACl were weighed and dissolved in isopropanol, and stirred at room temperature to obtain a perovskite precursor solution. A TFBSA solution was then mixed with the perovskite solution. In a nitrogen atmosphere, a perovskite precursor solution was spin-coated and annealed; the solute spiro-OMeTAD was dissolved in chlorobenzene, and then tBP and Li-TFSI acetonitrile solution were added and stirred at room temperature for 4 hours; the solution was transferred by pipette and spin-coated to prepare a hole transport layer; Ag electrode was prepared by vacuum magnetron sputtering.
2. The preparation method according to claim 1, characterized in that, In a natural environment, the order of rinsing the PEN / ITO substrate is: detergent, deionized water, and anhydrous ethanol. The order of ultrasonic cleaning of PEN / ITO is: anhydrous ethanol, deionized water, isopropanol, and anhydrous ethanol. The ultrasonic cleaning is performed for 15 minutes.
3. The preparation method according to claim 1, characterized in that, A 0.9 mg / ml trifluorobenzenesulfonamide solution was prepared by dilution with 1500 μL dimethylformamide and stirred at 70 °C for 12 h.
4. The preparation method according to claim 1, characterized in that, Weigh 900 mg lead iodide, 180 mg FAI, 18 mg MABr, and 18 mg MACl and dissolve them in 3 mL isopropanol. Stir at 70 °C for 12 h to obtain a perovskite precursor solution.
5. The preparation method according to claim 1, characterized in that, The TFBSA solution was mixed with the perovskite precursor solution and stirred for 4 h.
6. The preparation method according to claim 1, characterized in that, In a nitrogen atmosphere in a glove box, the PEN / ITO substrate with the prepared electron transport layer was placed on a spin coater. 80 μL of perovskite precursor solution was dropped onto the substrate, and the substrate was spin-coated at 1500 rpm for 10 s, and then at 5000 rpm for 30 s. At the 30th s of spin coating, chlorobenzene solution was quickly added. Immediately after spin coating was completed, the substrate was placed on an annealing station at 100℃ for 45 min using tweezers.
7. The preparation method according to claim 1, characterized in that, Dissolve 72.3 mg of 2,2',7,7'-tetratetra[N,N-di(4-methoxyphenyl)amino]-9,9'spirodifluorene in 1 ml of chlorobenzene, then add 28.8 μL of tert-butylpyridine and 17.5 μL of lithium bis(trifluoromethanesulfonyl)imide acetonitrile solution. After preparation, stir the solution at room temperature for 4 hours.