Highly efficient planar perovskite solar cells with a TiO2/ZnO electron transport bilayer

Abstract

A TiO₂/ZnO electron transport bilayer, which combines the advantages of high electron extraction and low interfacial recombination together, has been designed for planar perovskite solar cells. With this bilayer, the front surface recombination in the cell is significantly suppressed, and a high efficiency exceeding 17% has been achieved. These results suggest a promising and simple approach to further design photovoltaic devices from the aspect of charge transport and recombination.