Lead-Free Perovskite-Based Bifunctional Device for Both Photoelectric Conversion and Energy Storage

Integrating revolutionary perovskite solar cells with energy storage devices is a very promising technology to reduce the total cost of solar power utilization. Here, for the first time, lead-free (C 6 H 5 NH 3 )BiI 4 perovskite materials were used as light absorbers in low-cost triple-layer mesoscopic perovskite solar cells with a power conversion efficiency of 0.35%. We fabricated a dense and pinhole-free (C 6 H 5 NH 3 )BiI 4 perovskite film via homemade gas pump treatment equipment. We discovered storage characteristics in this carbon electrode-based, hole-conductor-free, and fully printable mesoporous solar cells infiltrated by (C 6 H 5 NH 3 )BiI 4 perovskite, which indicates that this type of device might work under dark conditions. This study may provide some useful inspiration for the further exploration of the potential of (C 6 H 5 NH 3 )BiI 4 as a lead-free candidate for the direct storage of electric energy in solar cells.