Preparation of high-performance antimicrobial agent based on ZnO/GODs-PEI composites. Nano ZnO is regarded as the effective antibacterial agents because of its distinctive photocatalytic properties. However, the fast recombination of photo-generated electrons and holes on the surface of ZnO seriously affects antibacterial activities. Therefore, numerous methods such as controlling the size and morphology of ZnO, doping metal and nonmetal ions, coupling semiconductor, constructing heterojunction and surface modification have been used to increase the activity of ZnO. The application aims to synthesize a stable low-dimensional ZnO/GQD aqueous with excellent dispersity and enhanced absorption to further improve its antibacterial activities. Hence, amphiphilic polyethylenimine-functionalized graphene quantum dots (GQD-PEI) was prepared firstly, which was then used to transfer ZnO NPs to water to obtain water-soluble ZnO/GODs-PEI composites.