Computational Study on Enhanced Conversion Efficiency of MAPbI3/$${\mathbf{CuIn}_{x}}{\mathbf{Ga}_{{1 - x}}}{\mathbf{Se}_{2}}$$ Heterojunction Solar Cells

This study focuses on optimizing the performance of MAPbI3/ $${\text{CuI}}{{{\text{n}}}_{x}}{\text{G}}{{{\text{a}}}_{{1 - x}}}{\text{S}}{{{\text{e}}}_{2}}$$ heterojunction solar cells to achieve enhanced efficiency through computational simulations using SCAPS-1D. We investigated the influence of variations in the Ga/Ga + In ratio within $$~{\text{CuI}}{{{\text{n}}}_{x}}{\text{G}}{{{\text{a}}}_{{1 - x}}}{\text{S}}{{{\text{e}}}_{2}}$$ the absorber layer on device performance. The simulation results revealed a direct correlation between the gallium content and the J–V parameters; we identified an optimum ratio that maximized the efficiency. Subsequently, we explored the effect of absorber layer thickness, acceptor density, interface defects, and operating temperature on device performance, focusing on the optimum gallium content in the $${\text{CuI}}{{{\text{n}}}_{x}}{\text{G}}{{{\text{a}}}_{{1 - x}}}{\text{S}}{{{\text{e}}}_{2}}$$ layer. Under optimized conditions, the results indicate that adjusting the gallium content can significantly enhance the designed solar cell performance, resulting in impressive characteristics, including an open-circuit voltage of 1.2847 V, a short-circuit current density of 25.2992 mA/cm2, a fill factor of 89.54%, and an overall efficiency of 29.10%. These findings highlight the crucial significance of the gallium content and provide valuable insights for advancing sustainable photovoltaic technologies.