Boosting the fill factor and open-circuit voltage of carbon-based perovskite solar cells with a graphene co-doped P3HT/NiOx hole-transporting bilayer

A low-temperature and solution-processed graphene co-doped G-P3HT/G-NiO x hole-transporting bilayer with enhanced conductivity and matched cascade band alignment is designed for high-performance carbon electrode perovskite solar cells.