Ag-Ion Doping Enables ZnO/MoS₂ Nanoarray Photoelectrochemical Photodetectors

In the present work, the exploration of photoelectrochemical (PEC) photodetectors (PDs) based on Ag-doped ZnO/MoS2 nanorod arrays is reported. Ag-ion doping optimizes the band structure of ZnO, reduces interface defect states, promotes the formation of an internal electric field, and significantly improves the photoelectric performance and stability of ZnO/MoS2 heterojunction PEC PDs. The PD exhibits excellent photodetection behavior, with a high photocurrent density (684.08 μA·cm–2), responsivity (2.207 mA W–1), and detectivity (11.3 × 108 Jones) under white-light illumination with an intensity of 310 mW cm–2 and a bias voltage of 0.6 V, which are approximately 2.7, 2.7, and 4.2 times higher than those of pure ZnO/MoS2, respectively. Furthermore, Ag doping significantly improves the self-powered photoelectric performance of the device, demonstrating excellent photoresponse characteristics under zero bias. This study reveals the mechanism by which Ag-ion doping improves the performance of ZnO/MoS2 photodetectors, providing fundamental support for the development of high-performance photoelectrochemical photodetectors.