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

BiFeO 3 (BFO) is a potentially important Pb‐free ferroelectric with a narrow bandgap and is expected to become a novel photodetector. The photocurrent in BFO 3 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 BFO 3 ‐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.