Flexible and Self‐Powered Photoelectrochemical‐Type Solar‐Blind Photodetectors Based on Ag Nanowires‐Embedded Amorphous Ga₂O₃ Films

Abstract

The development of flexible electronics for detecting solar‐blind deep ultraviolet (UV‐C) light holds great promise for emerging technologies. Here, flexible photoelectrochemical photodetectors (PEC‐PDs) are demonstrated for self‐powered solar‐blind UV‐C sensing based on one‐step radio frequency sputtered amorphous gallium oxide (a‐Ga2O3) thin films on indium tin oxide‐coated polyethylene naphthalate (ITO/PEN) substrates in a simple and low‐cost manner. Surface functionalization of the ITO/PEN substrates with silver nanowires (Ag NWs) successfully embedded within the a‐Ga2O3 films significantly enhances the optoelectronic performance. Incorporating Ag NWs reduces charge transfer resistance and potential barrier, while enhancing built‐in electric field at the Ag NWs/a‐Ga2O3 interface, synergistically facilitating efficient electron transport. Consequently, the Ag NW‐modified PEC‐PDs exhibit approximately two‐fold increases in key metrics including responsivity (11.23 mA W−1) and response times (0.07/0.09 s rise/decay) under 254 nm illumination compared to pristine devices. Moreover, the Ag NW‐functionalized PEC‐PDs demonstrate superb mechanical flexibility and fatigue durability, maintaining ≈95% of the initial photoresponse current and responsivity after 500 bending cycles. This work provides valuable insights into designing high‐performance flexible self‐powered PEC‐PDs through ingenious photoanode engineering.