Fabrication of ZnO:Ga nanoplates-rGO composite for high-performance self-powered ultraviolet photodetector application

• High-quality GZONSs-rGO composites were synthesized by the hydrothermal treatment and surface modification technique. • Three low-cost and simple-structure UV photodetectors based on ZnONSs, GZONSs and GZONSs-rGO composites were fabricated. • The GZONSs-rGO composites UV photodetector showed self-powered behaviour. • At 0 V bias, a high responsivity of 0.12 A/W and short decay time of 4.47 s for GZONSs-rGO composites UV photodetector were achieved. Self-powered ultraviolet (UV) photodetectors have evoked extensive interest due to their ultralow power consumption, sustainability and light weight. In this work, gallium-doped ZnO nanoplates (GZONSs) were first synthesized by a hydrothermal method, the GZONSs-reduced graphene oxide (rGO) composite was successfully fabricated via the hydrothermal treatment and surface modification technique. Using GZONSs-rGO composite as the photosensitive layer, an UV photodetector was constructed. The results demonstrated that GZONSs are uniformly anchored onto the surface of rGO, a good composite was obtained. This photodetector showed self-powered behaviour with excellent detection capability to 365 nm light. At zero bias, a high responsivity of 0.12 A/W and short decay time of 4.47 s were achieved. This work provides an efficient and straightforward approach for the fabrication of high-performance self-powered UV photodetectors.