Fast extraction of electron across the interface of nanowire CH3NH3PbI3/ZnO on flexible PET substrate

Nanowire perovskite CH3NH3PbI3 was successfully grown on cheap commercial PET substrate by a modified two-step spin-coating procedure, in which CH3NH3I solution with small amount of DMF was used. It was found that morphology and crystallization behavior of the nanowire perovskites depended strongly on the amount of DMF. Interfaced with ZnO thin films, the nanowire perovskites showed faster extraction of electron than the usual thin film perovskites, possibly due to the larger surface-to-volume ratio and better contact with ZnO. The specific charge injection rate Ket as high as 1.684 × 109/s was achieved, which could have the potential to enhance the performance of flexible perovskite solar cell.