The electron transport material has the great effect on the performance of hybrid perovskite solar cells. TiO2 is widely chosen as the electron transport layer due to its facile synthesis and excellent charge extraction capability. Here, for the first time, we utilize the hydrogen treated TiO2 as the electron transport layer for improving the performance of perovskite solar cells. The hydrogen treatment increases the Fermi level and conductivity of TiO2, and the device based on hydrogen treated TiO2 exhibits a power conversion efficiency of 13.15% compared with 9.45% for the reference device with untreated TiO2. The results highlight the importance of optimizing the electron transport material and provide a new route to fabricate highly efficient planar perovskite solar cells.

Graphical Abstract

Hydrogenated TiO2 as efficient electron transport layer of planar perovskite solar cell