W-doped TiO2 photoanode for high performance perovskite solar cell

Abstract

Titanium dioxide (TiO2) with dispersed W-doping shows its capability for efficient electron collection from perovskite to TiO2 in perovskite solar cell. The conduction band (CB) of TiO2 moves downward (positive shift) with increasing the tungsten (W) content, which enlarges the energy gap between the CB of TiO2 and the perovskite. Thus, the efficiency of electron injection from perovskite to TiO2 is increased. Due to the increased electron injection, W-doped TiO2 (≤0.2%W content) enhances the short-circuit photocurrent (Jsc) of perovskite solar cell and improves the performance of perovskite solar cell. Perovskite solar cell with 0.1% W-doped photoanode obtains the highest power conversion efficiency (η=10.6%), which shows enhancement by 13% in Jsc and by 17% in η, as compared with the undoped TiO2 perovskite solar cell.