Modifying perovskite solar cells with l(+)-cysteine at the interface between mesoporous TiO2 and perovskite

A typical trifunctional amino acid, l(+)-cysteine, is employed to modify the interface between mesoporous TiO₂ and perovskite film, and promotes the power conversion efficiency of perovskite solar cells from 11.5% to 14.4%.