▎ 摘　　要

Flexible photodetectors (PDs) have become the latest research interest owing to their potential applications in future implantable sensors and foldable/wearable optoelectronics. Ga2O3, an emerging ultrawide band gap semiconductor, is considered as the native photosensitive material for solar-blind PDs. The reported fabrication temperature of Ga2O3 films is usually above 600 degrees C, which hinders its practical application for flexible devices. In this work, flexible PDs based on graphene/amorphous Ga2O3 van der Waals heterojunctions are fabricated, which demonstrate promising photoresponse to solar-blind ultraviolet light. The device yields a high photo-to-dark current ratio (similar to 10(5)) and large responsivity (22.75 A/W) under 254 nm light illumination, which could be ascribed to the efficient photogenerated electron-hole pair separation by the strong built-in field. Moreover, flexible PDs also show long-term environmental stability and outstanding mechanical flexibility without any encapsulation. Our work provides a new potential candidate for realizing cost-effective high-performance flexible optoelectronic applications.