Environmentally Friendly High-Efficiency Solar Cell Integrating Cu 2 SnS 3 and MASnI 3

This work presents the design and optimization of a new lead-free high-performance dual-absorber solar cell combining Cu2SnS3 and MASnI3. The remarkable performance results from the complementary bandgaps of the Cu2SnS3and MASnI3 absorber layers, which enable broader light absorption, and the favorable band alignment of absorber and transport layers, that facilitates efficient carrier separation and extraction. The proposed structure, FTO/ETL/Cu2SnS3/MASnI3/HTL/Pt, achieved a high PCE of 35.67%, with aVOCof 0.94V,JSCof 43.64 mA/cm2, and FF of 86.80%. Key optimization of transport layers, thickness, doping, and defect densities, along with resistive and thermal loss analysis, ensured practical applicability. This research demonstrates the strong potential of lead-free solar cell configurations for environmentally safe and high-performance photovoltaic technologies.