Cerium modified rod-like ZnO graphene complex and its photocatalytic properties under visible-light irradiation

Abstract ZnO-based semiconductor photocatalysts have emerged from many catalysts and become research hotspots as non-toxic, odorless, and readily available raw materials. Ce-doped ZnO and graphene composites with different concentrations (0 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%) were only synthesized by hydrothermal method. The results show that Ce was successfully doped in ZnO by substituting zinc vacancy and compounded with graphene, and distributed uniformly in ZnO lattice. In terms of optical properties, compared with pure ZnO, the absorption of visible light is enhanced, the light response range is widened, the number of electrons that transition back to the ground state is reduced, which indicates that the photocarriers are effectively separated. Compared with the degradation efficiency of pure ZnO (20.28%), ZGCeO series samples showed superior photocatalytic performance, among which ZGCeO2 (2 wt%) samples had the highest photocatalytic activity and catalytic efficiency, and the degradation rate reached 99.12% within 80 min. In this experiment, 2 wt% is the best doping ratio.