Graphene quantum dot-sensitized GaP@ZnO nanocomposite for high-performance UV photodetectors

Zinc oxide (ZnO) has the advantages of wide bandgap, rich resources, simple preparation, and environmental friendliness, which is a type of ultraviolet (UV) detector material with great potential for development. However, the complicated preparation processes and complex device structures limit the application of ZnO UV detectors. Therefore, in this study, a high-performance UV detector was successfully fabricated based on graphene quantum dot-sensitized GaP@ZnO nanocomposite (GQDs/GaP@ZnO) thin films deposited using a simple spin-coating method. The GQDs/GaP@ZnO device exhibits higher responsivity of 142.2 A W-1, excellent detectivity of 1.1 x 10(12) Jones, and a higher external quantum efficiency of 4.85 x 10(4)% under the conditions of 365 nm UV light (0.078 mW cm(-2)) and external voltage of 6 V. In addition, this study provides a new research method for the preparation of high-performance optoelectronic devices using the cumulative synergistic effect of material composites and surface modification.