System and method for improving conversion efficiency of solar cell by using circularly polarized light

Abstract

The invention relates to a system and method for improving the conversion efficiency of a solar cell by using circularly polarized light, and belongs to the technical field of solar cell light energy conversion. Conventional non-polarized light is converted into circularly polarized light, and the spin direction of excited carriers in the solar cell is regulated and controlled to be matched with the spin selectivity of the cell, so that the transport efficiency of the carriers and the light energy conversion efficiency are improved. Experiments show that in a chiral dye-sensitized solar cell, an organic photovoltaic cell and a perovskite solar cell, the photoelectric conversion efficiency can be remarkably improved by adopting circular polarized light irradiation. The invention provides a novel optical regulation and control strategy for efficient light energy utilization of the solar cell.

Description

Technical Field

[0001] This invention relates to a system and method for improving the efficiency of solar cells using circularly polarized light, belonging to the field of solar cell technology, and particularly to a system and method for improving the photoelectric conversion efficiency of solar cells by controlling the spin state of charge carriers through optical polarization. Background Technology

[0002] Solar cells are key devices that directly convert light energy into electrical energy. Their efficiency is affected by many factors, including light absorption, carrier separation, and transport. In traditional solar cells, under unpolarized light irradiation, the excited carriers have random spin directions, causing some carriers to scatter or recombine during transport due to spin mismatch, thus reducing energy conversion efficiency. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a system and method for improving the conversion efficiency of solar cells by using circularly polarized light. This method converts unpolarized light into circularly polarized light through a polarization optical system, so as to match it with the spin selectivity of the solar cell, thereby improving the photoelectric conversion efficiency.

[0004] The technical solution of the present invention includes:

[0005] A system for improving the conversion efficiency of solar cells using circularly polarized light, the system comprising a solar simulator, a polarization optics system, a solar cell, and an efficiency evaluation system; A polarizing optical system consists of a linear polarizer and a quarter-wave plate, which can convert unpolarized light into left-handed or right-handed circularly polarized light; The solar simulator is used to simulate sunlight and output simulated sunlight to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate converts the received linearly polarized light into circularly polarized light for the solar cell. Solar cells convert received circularly polarized light into electrical energy and output the electrical energy to an efficiency evaluation system; The efficiency evaluation system assesses the performance of solar cells based on the received electrical energy.

[0006] The quarter-wave plate is an achromatic wave plate to reduce wavelength-dependent loss; The solar cell is at least one of dye-sensitized solar cells, organic photovoltaic cells, and perovskite solar cells; The solar cell has a spin-selective interface or a chiral structure, which can selectively transport charge carriers with a set spin direction. The dye-sensitized solar cell is a dye-sensitized solar cell modified with a chiral dye; The organic photovoltaic cell is a chiral organic photovoltaic cell; The perovskite solar cell is a chiral ligand-modified or chiral A-site perovskite solar cell; A method for improving the conversion efficiency of solar cells using circularly polarized light, the method comprising the following steps: The first step involves outputting simulated sunlight from a solar simulator to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate then converts the received linearly polarized light into circularly polarized light for use with the solar cell. The second step involves the solar cell converting the received circularly polarized light into electrical energy and then outputting that electrical energy to the efficiency evaluation system. The third step involves the efficiency evaluation system assessing the performance of the solar cells based on the received electrical energy.

[0007] The polarization direction of the circularly polarized light matches the spin selectivity direction of the solar cell; In the first step, the calibration method for the simulated sunlight intensity output by the solar simulator is as follows: The light intensity was calibrated to 100 mW·cm using a standard silicon cell. - ²; The intensity of circularly polarized light is also calibrated to 100 mW·cm using a standard silicon cell. - ²; The method for preparing the dye-sensitized solar cell is as follows: FTO glass is ultrasonically cleaned sequentially in water, ethanol, and acetone. Then, a TiO2 porous film is spin-coated onto the surface of the FTO glass, and the glass is sintered in a muffle furnace at 500 °C for 4 h. After natural cooling, the glass is immersed in a chiral dye solution (such as chlorophyll) for 24 h to obtain the photoanode. Finally, the photoanode is assembled with a platinum counter electrode and an iodine electrolyte, and then encapsulated to ensure stability. The organic photovoltaic cell is prepared based on an ITO / ZnO / PTB7-Th:(S,S)-IE4F / MoO3 / Ag structure. First, a ZnO precursor solution is spin-coated onto the ITO glass surface and annealed at 200 °C to form a ZnO electron transport layer. Then, the active layer materials PTB7-Th and (S,S)-IE4F are spin-coated in an inert atmosphere and annealed at 100 °C. Finally, MoO3 and Ag are vacuum-deposited, and encapsulation is performed to ensure stability. The perovskite solar cell employs a nip-type planar structure. The process involves sequentially spin-coating an electron transport layer material (dense TiO2 / SnO2) precursor solution onto an ITO / FTO substrate, followed by annealing of the TiO2 at 450 °C and the SnO2 at 150 °C; annealing of the MAPbI3 precursor solution at 100 °C; drying the hole transport layer material (Spiro-OMeTAD) at room temperature; and finally, vacuum-depositing gold electrodes to complete the device construction. Encapsulation is performed during assembly to ensure stability. The method for evaluating the performance of solar cells in the third step is as follows: First, the JV standard curve of the solar cell was measured under unpolarized light; Subsequently, by adjusting the angle of the quarter-wave plate to generate circularly polarized light with a set rotation direction, the JV test curve of the solar cell was measured again. The conversion efficiency of solar cells under unpolarized and polarized light conditions is obtained by calculating the JV standard curve and JV test curve, and the effect of circularly polarized light on improving the performance of solar cells is evaluated. Throughout the process, attention should be paid to the cleanliness of optical components, the collimation of the optical path, and the encapsulation protection of the devices to ensure the reliability of the test results.

[0008] Beneficial effects This invention relates to a system and method for improving the conversion efficiency of solar cells using circularly polarized light, belonging to the field of solar cell light energy conversion technology. By converting conventional unpolarized light into circularly polarized light, the spin direction of excited carriers in the solar cell is modulated to match the cell's spin selectivity, thereby improving carrier transport efficiency and light energy conversion efficiency. Experiments show that circularly polarized light irradiation can significantly improve the photoelectric conversion efficiency in chiral dye-sensitized solar cells (DSSC), organic photovoltaic (OPV), and perovskite solar cells. This invention provides a novel optical control strategy for the efficient utilization of solar energy in solar cells.

[0009] This invention significantly improves the photoelectric conversion efficiency of various solar cells through simple optical polarization modulation, and has the following advantages: simple system structure, easy to integrate; applicable to various solar cell systems; efficiency improvement is achieved solely through optical means without changing the cell structure or materials. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the system composition of the present invention; Figure 2 The JV standard curve for chlorophyll dye-sensitized solar cells; Figure 3 The JV test curve is for a chlorophyll dye-sensitized cell. Detailed Implementation

[0011] The present invention will be described in detail below with reference to the embodiments, but the scope of protection of the present invention is not limited thereto.

[0012] Example 1 like Figure 1 As shown, a system for improving the conversion efficiency of solar cells using circularly polarized light is described. The system includes a solar simulator, a polarization optics system, a solar cell, and an efficiency evaluation system. A polarizing optical system consists of a linear polarizer and a quarter-wave plate, which can convert unpolarized light into left-handed or right-handed circularly polarized light; The solar simulator is used to simulate sunlight and output simulated sunlight to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate converts the received linearly polarized light into circularly polarized light for the solar cell. Solar cells convert received circularly polarized light into electrical energy and output the electrical energy to an efficiency evaluation system; The efficiency evaluation system assesses the performance of solar cells based on the received electrical energy.

[0013] The quarter-wave plate is an achromatic wave plate to reduce wavelength-dependent loss; The solar cell is a chiral dye (chlorophyll) sensitized solar cell (DSSC), and its preparation method is as follows: (1) Prepare two FTO glass pieces, namely FTO glass A and FTO glass B. Both FTO glass pieces are ultrasonically cleaned in water, ethanol and acetone in sequence. After ultrasonic cleaning, UV-O3 treatment is performed. Then, nano TiO2 slurry is scraped or spin-coated on FTO glass A to form a porous layer with a thickness of 8-12 μm. Then, FTO glass A with the porous layer is placed in a muffle furnace. First, the temperature is raised to 100 ℃ for 20 min. Then, the temperature is raised to 500 ℃ for 1 h. Then, it is kept at the temperature for 4 h. After the temperature is kept at the temperature, it is naturally cooled to room temperature. FTO glass A is then taken out and soaked in an ethanol solution containing chlorophyll dye for 24 h. After rinsing and drying, it is ready for use. The concentration of chlorophyll dye is 0.3 mM. (2) H2PtCl6 solution was drop-coated onto the conductive surface of FTO glass B, and then the FTO glass B with H2PtCl6 solution was thermally decomposed at 400 °C to obtain a catalyst layer. (3) The FTO glass A obtained in step (1) and the FTO glass B with a catalyst layer obtained in step (2) are encapsulated with a hot melt adhesive frame, the thickness of which is 25–60 μm; then, the hot melt adhesive is hot-pressed into a cavity at 100 °C, and then I is injected using the vacuum back injection method. - / I3 - Electrolytes are used to obtain solar cells; I - / I3 - The electrolyte is a mixed acetonitrile solution containing I2, LiI, DMII, and tBP, wherein the concentration of I2 is 0.05 M, the concentration of LiI is 0.5 M, the concentration of DMII is 0.6 M, and the concentration of tBP is 0.5 M. A method for improving the conversion efficiency of chiral dye (chlorophyll) sensitized solar cells using circularly polarized light, the method comprising the following steps: The first step involves outputting simulated sunlight from an AM 1.5G solar simulator to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The fast axis of the quarter-wave plate makes an angle of +45° with the polarization direction, generating right-hand circularly polarized light (RCP). The light is then adjusted to 100 mW·cm using a calibration Si standard. - ²; The second step involves the solar cell converting the received circularly polarized light into electrical energy and then outputting that electrical energy to the efficiency evaluation system. The third step involves the efficiency evaluation system performing a J-V scan of the solar cell based on the received electrical energy, resulting in a J-V test curve; the horizontal axis of the J-V test curve is scanned within this range. 0.1 to 1 V; The method for obtaining the J–V standard curve is as follows: The light intensity was adjusted to 100 mW·cm using a calibrated Si standard wafer. - ², simulated sunlight is output to the solar cells via an AM 1.5G solar simulator. The solar cells convert the received sunlight into electrical energy and output the electrical energy to an efficiency evaluation system. The efficiency evaluation system performs a J-V scan of the solar cells based on the received electrical energy to obtain a J-V standard curve; the horizontal axis of the J-V standard curve scans within a certain range. 0.1 to 1 V; The conversion efficiency, calculated based on the obtained J–V standard curve, is 1.5%. The conversion efficiency was calculated to be 1.8% based on the obtained J-V test curve, representing a relative improvement of approximately 20%.

[0014] Example 2 A system for improving the conversion efficiency of solar cells using circularly polarized light, the system comprising a solar simulator, a polarization optics system, a solar cell, and an efficiency evaluation system; A polarizing optical system consists of a linear polarizer and a quarter-wave plate, which can convert unpolarized light into left-handed or right-handed circularly polarized light; The solar simulator is used to simulate sunlight and output simulated sunlight to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate converts the received linearly polarized light into circularly polarized light for the solar cell. Solar cells convert received circularly polarized light into electrical energy and output the electrical energy to an efficiency evaluation system; The efficiency evaluation system assesses the performance of solar cells based on the received electrical energy.

[0015] The quarter-wave plate is an achromatic wave plate to reduce wavelength-dependent loss; The solar cell is an organic photovoltaic (OPV) based on indenopythiophene chiral acceptor material, and its preparation method is as follows: First, the ITO glass was ultrasonically cleaned and treated with UV-O3 sequentially in water, ethanol, and acetone. Then, a ZnO precursor solution was spin-coated and annealed at 200 °C to deposit a ZnO electron transport layer. A PTB7-Th:(S,S)-IE4F mixed solution was spin-coated in a nitrogen glove box and annealed at 100 °C to form an active layer (approximately 100 nm). MoO3 (5–10 nm) and Ag (80–120 nm) were deposited using a shadow mask to define the effective area and perform simple encapsulation.

[0016] The ZnO precursor solution used zinc acetate dihydrate as the zinc source, ethylene glycol methyl ether as the solvent, and ethanolamine as the stabilizer, with both zinc acetate dihydrate and ethanolamine at a concentration of 0.2 M; the concentration of the PTB7-Th:(S,S)-IE4F mixed solution was 18 mg·ml. -1 The mass ratio of PTB7-Th to (S,S)-IE4F is 1:1, and the solvent is chlorobenzene containing 0.5% (v / v) 1,8-diiodooctane. A method for improving the conversion efficiency of organic photovoltaic cells using circularly polarized light, the method comprising the following steps: The first step involves outputting simulated sunlight from an AM 1.5G solar simulator to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The fast axis of the quarter-wave plate forms an angle of -45° with the polarization direction, generating left-handed circularly polarized light (LCP). The light is then adjusted to 100 mW·cm using a calibration Si standard. -²; The second step involves the solar cell converting the received circularly polarized light into electrical energy and then outputting that electrical energy to the efficiency evaluation system. The third step involves the efficiency evaluation system performing a J-V scan of the solar cell based on the received electrical energy, resulting in a J-V test curve; the horizontal axis of the J-V test curve is scanned within this range. 0.1 to 1 V; The method for obtaining the J–V standard curve is as follows: The light intensity was adjusted to 100 mW·cm using a calibrated Si standard wafer. - ², simulated sunlight is output to the solar cells via an AM 1.5G solar simulator. The solar cells convert the received sunlight into electrical energy and output the electrical energy to an efficiency evaluation system. The efficiency evaluation system performs a J-V scan of the solar cells based on the received electrical energy to obtain a J-V standard curve; the horizontal axis of the J-V standard curve scans within a certain range. 0.1 to 1 V; The conversion efficiency was calculated to be 7.9% based on the obtained J–V standard curve. The conversion efficiency was calculated to be 9.4% based on the obtained J-V test curve, representing a relative improvement of approximately 19%.

[0017] Example 3 A system for improving the conversion efficiency of solar cells using circularly polarized light, the system comprising a solar simulator, a polarization optics system, a solar cell, and an efficiency evaluation system; A polarizing optical system consists of a linear polarizer and a quarter-wave plate, which can convert unpolarized light into left-handed or right-handed circularly polarized light; The solar simulator is used to simulate sunlight and output simulated sunlight to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate converts the received linearly polarized light into circularly polarized light for the solar cell. Solar cells convert received circularly polarized light into electrical energy and output the electrical energy to an efficiency evaluation system; The efficiency evaluation system assesses the performance of solar cells based on the received electrical energy.

[0018] The quarter-wave plate is an achromatic wave plate to reduce wavelength-dependent loss; The solar cell is a chiral organic amine-induced (R / S-MBA)2PbI4 perovskite solar cell (PSC), and its preparation method is as follows: First, the ITO glass was ultrasonically cleaned and treated with UV-O3 sequentially in water, ethanol, and acetone. Then, a SnO2 precursor solution was spin-coated onto the ITO glass and annealed at 200 °C to form an electron transport layer. A (R / S-MBA) 2PbI4 precursor solution was spin-coated and annealed at 100 °C on a heating stage to obtain an absorption layer. A Spiro-OMeTAD doping solution was spin-coated. An Au electrode (with an area limited to 0.1 cm²) was vacuum evaporated and then encapsulated.

[0019] The SnO2 precursor solution was an ethanolic solution of SnCl4 with a concentration of 0.1 M; the (R / S-MBA)2PbI4 precursor solution was PbI2 and (S)-MBA dissolved in a DMF / DMSO mixed solvent (volume ratio 7:3) at a molar ratio of 1:2 with a concentration of 0.2 M; the Spiro-OMeTAD doping solution was Spiro-OMeTAD dissolved in chlorobenzene with a concentration of 80 mg / ml. -1 .

[0020] A method for improving the conversion efficiency of (R / S-MBA) 2PbI4 perovskite solar cells using circularly polarized light, the method comprising the following steps: The first step involves outputting simulated sunlight from an AM 1.5G solar simulator to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The fast axis of the quarter-wave plate forms an angle of -45° with the polarization direction, generating left-handed circularly polarized light (LCP). The light is then adjusted to 100 mW·cm using a calibration Si standard. - ²; The second step involves the (S-MBA)2PbI4 perovskite solar cell converting the received circularly polarized light into electrical energy and outputting the electrical energy to the efficiency evaluation system. The third step involves the efficiency evaluation system performing a J-V scan of the solar cell based on the received electrical energy, resulting in the J-V test curve A; the horizontal axis of the J-V test curve is scanned within this range. 0.1 to 1 V; The fourth step involves adjusting the angle between the fast axis of the quarter-wave plate and the polarization direction to +45° to generate right-hand circularly polarized light (RCP), and then adjusting the light to 100 mW·cm using a calibration Si standard plate. - ²; The J–V test curve B was obtained by testing (R-MBA)2PbI4 perovskite solar cells using the same method; the horizontal axis scan range of the J–V test curve. 0.1 to 1 V; The method for obtaining the J–V standard curve is as follows: The light intensity was adjusted to 100 mW·cm using a calibrated Si standard wafer. - ², simulated sunlight is output to a (S-MBA) 2PbI4 perovskite solar cell via an AM 1.5G solar simulator. The solar cell converts the received sunlight into electrical energy and outputs the electrical energy to an efficiency evaluation system. The efficiency evaluation system performs a J-V scan of the solar cell based on the received electrical energy, obtaining the J-V standard curve A; the horizontal axis of the J-V standard curve scans within a certain range. 0.1 to 1 V; The standard J-V curve B for (R-MBA) 2PbI4 perovskite solar cells was obtained using the same method; the x-axis range of the J-V test curve is shown. 0.1 to 1 V; The conversion efficiency was calculated to be 16.9% based on the obtained J–V standard curve A. The conversion efficiency was calculated to be 20.4% based on the obtained J-V test curve A, representing a relative improvement of 21%.

[0021] The conversion efficiency, calculated based on the obtained J–V standard curve B, is 17.0%. The conversion efficiency was calculated to be 20.9% based on the obtained J-V test curve B, representing a relative improvement of 23%.

[0022] Example 4 A system for improving the conversion efficiency of solar cells using circularly polarized light, the system comprising a solar simulator, a polarization optics system, a solar cell, and an efficiency evaluation system; A polarizing optical system consists of a linear polarizer and a quarter-wave plate, which can convert unpolarized light into left-handed or right-handed circularly polarized light; The solar simulator is used to simulate sunlight and output simulated sunlight to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate converts the received linearly polarized light into circularly polarized light for the solar cell. Solar cells convert received circularly polarized light into electrical energy and output the electrical energy to an efficiency evaluation system; The efficiency evaluation system assesses the performance of solar cells based on the received electrical energy.

[0023] The quarter-wave plate is an achromatic wave plate to reduce wavelength-dependent loss; The solar cell is a chiral ligand post-treatment MAPbI3 perovskite solar cell, and the preparation method is as follows: First, the ITO glass was ultrasonically cleaned and treated with UV-O3 in water, ethanol, and acetone in sequence. A TiO2 precursor solution was spin-coated and sintered at 400 °C to form a dense TiO2 layer. Then, a PbI2 precursor solution and a MAI precursor solution were spin-coated sequentially and annealed at 100 °C. Next, a chiral amine solution was drop-coated, cleaned, and dried. A Spiro-OMeTAD doping solution was spin-coated and dried at room temperature to form a film. An Au electrode (with an area limited to 0.1 cm²) was vacuum-evaporated and then encapsulated.

[0024] The TiO2 precursor solution was an ethanol solution of tetrabutyl titanate at a concentration of 0.1 M; the MAPbI3 precursor solution was [missing information]; the chiral amine solution was a saturated ethyl acetate solution of S-MBA:Br; and the Spiro-OMeTAD doping solution was Spiro-OMeTAD dissolved in chlorobenzene at a concentration of 80 mg / ml. -1 .

[0025] A method for improving the conversion efficiency of MAPbI3 perovskite solar cells by utilizing circularly polarized light after chiral ligand post-treatment, the method comprising the following steps: The first step involves outputting simulated sunlight from an AM 1.5G solar simulator to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The fast axis of the quarter-wave plate forms an angle of -45° with the polarization direction, generating left-handed circularly polarized light (LCP). The light is then adjusted to 100 mW·cm using a calibration Si standard. - ²; The second step involves the solar cell converting the received circularly polarized light into electrical energy and then outputting that electrical energy to the efficiency evaluation system. The third step involves the efficiency evaluation system performing a J-V scan of the solar cell based on the received electrical energy, resulting in a J-V test curve; the horizontal axis of the J-V test curve is scanned within this range. 0.1 to 1 V; The method for obtaining the J–V standard curve is as follows: The light intensity was adjusted to 100 mW·cm using a calibrated Si standard wafer. - ², simulated sunlight is output to the solar cells via an AM 1.5G solar simulator. The solar cells convert the received sunlight into electrical energy and output the electrical energy to an efficiency evaluation system. The efficiency evaluation system performs a J-V scan of the solar cells based on the received electrical energy to obtain a J-V standard curve; the horizontal axis of the J-V standard curve scans within a certain range. 0.1 to 1 V; The conversion efficiency, calculated based on the obtained J–V standard curve, is 16.0%. The conversion efficiency was calculated to be 19.5% based on the obtained J-V test curve, representing a relative improvement of approximately 22%.

[0026] Example 5 A system for improving the conversion efficiency of solar cells using circularly polarized light, the system comprising a solar simulator, a polarization optics system, a solar cell, and an efficiency evaluation system; A polarizing optical system consists of a linear polarizer and a quarter-wave plate, which can convert unpolarized light into left-handed or right-handed circularly polarized light; The solar simulator is used to simulate sunlight and output simulated sunlight to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate converts the received linearly polarized light into circularly polarized light for the solar cell. Solar cells convert received circularly polarized light into electrical energy and output the electrical energy to an efficiency evaluation system; The efficiency evaluation system assesses the performance of solar cells based on the received electrical energy.

[0027] The quarter-wave plate is an achromatic wave plate to reduce wavelength-dependent loss; The solar cell is an L-cysteine-induced chiral FAPbI3 perovskite solar cell, and its fabrication method is as follows: First, the FTO glass was ultrasonically cleaned and treated with UV-O3 sequentially in water, ethanol, and acetone. A SnO2 precursor solution was spin-coated and annealed at 200 °C to form an electron transport layer. A FAPbI3 precursor was spin-coated and annealed at 100 °C for 10 min. An L-cys solution was spin-coated, treated, cleaned, and dried. A Spiro-OMeTAD doping solution was spin-coated and dried at room temperature to form a film. An Au electrode (area limited to 0.1 cm²) was vacuum-evaporated and encapsulated if necessary.

[0028] The SnO2 precursor solution was an ethanolic solution of SnCl4 with a concentration of 0.1 M; the FAPbI3 precursor solution was a 1:1 molar ratio of FAI to PbI2 dissolved in DMF with a concentration of 0.8 M; the L-cys solution was L-cysteine ​​and HI dissolved in ethanol, with L-cysteine ​​at a concentration of 0.1 M and HI at a concentration of 15 mM; the Spiro-OMeTAD doping solution was Spiro-OMeTAD dissolved in chlorobenzene with a concentration of 80 mg / mL. -1 .

[0029] A method for improving the conversion efficiency of L-cysteine-induced chiral FAPbI3 perovskite solar cells using circularly polarized light, the method comprising the following steps: The first step involves outputting simulated sunlight from an AM 1.5G solar simulator to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The fast axis of the quarter-wave plate forms an angle of -45° with the polarization direction, generating left-handed circularly polarized light (LCP). The light is then adjusted to 100 mW·cm using a calibration Si standard. - ²; The second step involves the solar cell converting the received circularly polarized light into electrical energy and then outputting that electrical energy to the efficiency evaluation system. The third step involves the efficiency evaluation system performing a J-V scan of the solar cell based on the received electrical energy, resulting in a J-V test curve; the horizontal axis of the J-V test curve is scanned within this range. 0.1 to 1 V; The method for obtaining the J–V standard curve is as follows: The light intensity was adjusted to 100 mW·cm using a calibrated Si standard wafer. - ², simulated sunlight is output to the solar cells via an AM 1.5G solar simulator. The solar cells convert the received sunlight into electrical energy and output the electrical energy to an efficiency evaluation system. The efficiency evaluation system performs a J-V scan of the solar cells based on the received electrical energy to obtain a J-V standard curve; the horizontal axis of the J-V standard curve scans within a certain range. 0.1 to 1 V; The conversion efficiency, calculated based on the obtained J–V standard curve, is 17.5%. The conversion efficiency was calculated to be 21.0% based on the obtained J-V test curve, representing a relative improvement of 20%.

[0030] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A system for improving the conversion efficiency of solar cells using circularly polarized light, characterized in that: The system includes a solar simulator, a polarization optics system, solar cells, and an efficiency evaluation system; The polarization optical system consists of a linear polarizer and a quarter-wave plate, which can convert unpolarized light into left-handed or right-handed circularly polarized light. The solar simulator is used to simulate sunlight and output simulated sunlight to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate converts the received linearly polarized light into circularly polarized light for the solar cell. The solar cell converts the received circularly polarized light into electrical energy and outputs the electrical energy to the efficiency evaluation system; The efficiency evaluation system evaluates the performance of the solar cell based on the received electrical energy.

2. The system for improving the conversion efficiency of solar cells using circularly polarized light according to claim 1, characterized in that: The quarter-wave plate is an achromatic wave plate; The solar cell is at least one of dye-sensitized solar cells, organic photovoltaic cells, and perovskite solar cells; The dye-sensitized solar cell is a dye-sensitized solar cell modified with a chiral dye; The organic photovoltaic cell is a chiral organic photovoltaic cell; The perovskite solar cell is a chiral ligand-modified or chiral A-site perovskite solar cell.

3. A method for improving the conversion efficiency of solar cells using circularly polarized light, characterized in that... The steps of this method include: The first step involves outputting simulated sunlight from a solar simulator to a linear polarizer. The linear polarizer polarizes the received simulated sunlight and outputs linearly polarized light to a quarter-wave plate. The quarter-wave plate then converts the received linearly polarized light into circularly polarized light for use with the solar cell. The second step involves the solar cell converting the received circularly polarized light into electrical energy and then outputting that electrical energy to the efficiency evaluation system. The third step involves the efficiency evaluation system assessing the performance of the solar cells based on the received electrical energy.

4. The method for improving the conversion efficiency of a solar cell using circularly polarized light according to claim 3, characterized in that: The polarization direction of the circularly polarized light matches the spin selectivity direction of the solar cell.

5. A method for improving the conversion efficiency of a solar cell using circularly polarized light according to claim 3, characterized in that: In the first step, the calibration method for the simulated sunlight intensity output by the solar simulator is as follows: The light intensity was calibrated to 100 mW·cm using a standard silicon cell. - ²; The intensity of circularly polarized light was calibrated to 100 mW·cm using a standard silicon cell. - ².

6. The method for improving the conversion efficiency of a solar cell using circularly polarized light according to claim 3, characterized in that: The fabrication method of the dye-sensitized solar cell is as follows: FTO glass is ultrasonically cleaned sequentially in water, ethanol, and acetone. Then, a TiO2 porous film is spin-coated on the surface of the FTO glass, and the glass is sintered in a muffle furnace at 500 °C for 4 h. After natural cooling, the glass is immersed in a chiral dye solution for 24 h to obtain a photoanode. Finally, the photoanode is assembled with a platinum counter electrode and an iodine electrolyte, and then encapsulated to ensure stability.

7. A method for improving the conversion efficiency of a solar cell using circularly polarized light according to claim 3, characterized in that: The organic photovoltaic cell is prepared as follows: Based on the ITO / ZnO / PTB7-Th:(S,S)-IE4F / MoO3 / Ag structure, firstly, a ZnO precursor solution is spin-coated onto the surface of ITO glass and annealed at 200 °C to form a ZnO electron transport layer. Then, active layer materials PTB7-Th and (S,S)-IE4F are spin-coated in an inert atmosphere and annealed at 100 °C. Finally, MoO3 and Ag are vacuum-deposited and encapsulated to ensure stability.

8. A method for improving the conversion efficiency of a solar cell using circularly polarized light according to claim 3, characterized in that: The perovskite solar cell adopts a nip-type planar structure. It is constructed by sequentially spin-coating an electron transport layer material, a dense TiO2 / SnO2 precursor solution, onto an ITO / FTO substrate, followed by annealing of the TiO2 at 450 °C and the SnO2 at 150 °C; and then annealing the MAPbI3 precursor solution at 100 °C. Spiro-OMeTAD, a hole transport layer material, is dried to form a film at room temperature; finally, gold electrodes are vacuum-deposited to complete the device construction, and encapsulation is performed during assembly to ensure stability.

9. A method for improving the conversion efficiency of a solar cell using circularly polarized light according to claim 3, characterized in that: The method for evaluating the performance of solar cells in the third step is as follows: First, the JV standard curve of the solar cell was measured under unpolarized light; Subsequently, by adjusting the angle of the quarter-wave plate to generate circularly polarized light with a set rotation direction, the JV test curve of the solar cell was measured again. The conversion efficiency of solar cells under unpolarized and polarized light conditions was calculated by using the JV standard curve and JV test curve, and the effect of circularly polarized light on improving the performance of solar cells was evaluated.

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