Boosting Photocurrent via Heating BiFeO3 Materials for Enhanced Self‐Powered UV Photodetectors

Abstract BiFeO3 (BFO) is a potentially important Pb‐free ferroelectric with a narrow bandgap and is expected to become a novel photodetector. The photocurrent in BFO3 strongly depends on the temperature but only a few studies have investigated in detail the relationships between photocurrent and temperature. Here, the temperature‐dependent photocurrent and the corresponding photosensing properties of a Ag/BFO/indiumtin oxide (ITO) photodetector based on an optimized planar‐structured electrode configuration are investigated. The photocurrent and responsivity of the BFO3‐based photodetector can first be increased and then be decreased with increasing temperature. The largest photocurrent and responsivity can reach 51.5 µA and 6.56 × 10−4 A W−1 at 66.1 °C, which is enhanced 126.3% as compared with that at room temperature. This may be caused by the temperature‐modulated bandgap and barrier height in Ag/BFO/ITO device. This study clarifies the relationship between photosensing performance and the operating temperature of BFO‐based photodetector and will push forward the application of ferroelectric materials in photoelectric field.