In recent years, notable progress has been made in the field of perovskite-perovskite junctions, including the effective implementation of a structural assembly engineering technique to enhance the performance of perovskite solar cells (PSCs). A comprehensive investigation of a heterojunction structure consisting of absorber layers composed of CsPbI3 and CsPbBr3 was conducted via the implementation of SCAPS-1D simulation. The motivation for depositing CsPbBr3 onto CsPbI3 is to utilize it as a protective layer that inhibits or mitigates the ongoing degradation of CsPbI3. This study examines the influence of several factors on the performance of absorbers, including absorber thickness, band offset, trap-assisted defect density, working temperature, work function, series and shunt resistance, and doping level. The addition of a CsPbBr3 layer was shown to significantly boost the photovoltaic performance of CsPbI3 PSCs. Furthermore, the functioning of heterojunction PSCs is highly dependent upon the operating temperature and density of defects. The device with the FTO/ZnOS/CsPbI3/CsPbBr3/CZTS configuration demonstrated impressive power conversion efficiency (PCE), open-circuit voltage (VOC), current density voltage (JSC), and fill factor (FF) values of 22.12%, 1.26 V, 20.62 mA/cm2, and 84.86%, respectively. These findings will offer valuable theoretical insights into the enhancement and production of PSCs with improved efficiency and stability.

Optimizing the working mechanism of CsPbI3/CsPbBr3 heterojunction solar cells using SCAPS-1D