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 (C6H5NH3)BiI4 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 (C6H5NH3)BiI4 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 (C6H5NH3)BiI4 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 (C6H5NH3)BiI4 as a lead-free candidate for the direct storage of electric energy in solar cells.