Metal halide perovskite solar cells (PSCs) have gained significant attention in thin-film photovoltaic research for their high power conversion efficiency (PCE) and facile fabrication processes. This study presents the use of inkjet printing to fabricate thin films of combinatorial mixed formamidinium tin-lead perovskites and evaluates their layer quality and device performance. Our findings demonstrate that incorporating Pb up to 50% into FASnI3 films enhances lattice stability. The investigation focused on optimizing the composition ratio for improved photovoltaic performance with FASn0.5Pb0.5I3-based PSCs achieving the highest PCE of 10.26%. Additionally, these cells exhibited an absorption spectrum extending beyond 1000 nm, corresponding to a 1.25 eV bandgap. The results suggest that inkjet printing can effectively enhance the efficiency of tin-lead-based PSCs, supporting scalability in device manufacturing.
Keywords: NIR-region solar cells; band gap tuning; inkjet printing; low bandgap solar cells; tandem applications; tin−lead perovskites.