An efficient TiO2 electron transport layer for compact TiO2/polycrystalline BiFeO3 heterostructure thin film with enhanced photovoltaic performance

In this letter, high-performance TiO2/BiFeO3 heterostructure thin film is successfully prepared by introducing sol-gel derived-TiO2 (SG-TiO2) electron transport layer. A significant improvement of photovoltaic performance has been achieved. 3.674% power conversion efficiency of the thin film is obtained with open-circuit voltage (Voc) of 1.64 V, short-circuit photocurrent (Jsc) of 3.5 mA/cm2 and fill factor (FF) of 64%, which implies that the introduction of a TiO2 would improve the photovoltaic performance under visible light illumination. Our work demonstrates that the TiO2/BFO heterostructure thin film possesses the potential for better use in the solar energy devices applications.