High-performance optimization and analysis of Cs₂CuSbCl₆-Based lead-free double perovskite solar cells with theoretical efficiency exceeding 27 %

The primary challenges in photovoltaic solar energy include toxicity, stability, and the cost of solar cells. To address these issues, we propose the use of noble metal halide double perovskites, which are lead-free. Cs2CuSbCl6 stands out as a popular absorber due to its huge bandgap, high absorption coefficient, and affordable price. Our research analyzes and simulates solar cells with Cs₂CuSbCl₆ as the absorber material, utilizing SCAPS-1D software. Along with AZnO for the electron transport layer (ETL), we assess the material's stability and suggest less expensive substitutes for hole transport materials (HTLs) such as Spiro-OMeTAD, MoO₃, NiO, Cu2O, and CuSCN. Our goal is to find the ideal values for important photovoltaic parameters to increase the efficiency of the suggested solar cells. This entails examining how the thickness, temperature, and doping level affect the properties of the solar cell. Furthermore, numerous feasible back electrodes are investigated and their impact on performance is assessed to replace the pricey gold (Au) electrode. We discovered that the optimal configuration for Cs2CuSbCl6 is C (metal back contact)/MoO3 (HTM)/Cs2CuSbCl6 (Absorber)/AZnO (ETM)/FTO, resulting in 300 K performance. PCE: 27.56 %, Voc: 1.47 V, Jsc: 20.66 mA/cm2, and FF 89.83 %.