Boosting photocatalytic degradation efficiency of tetracycline by a visible-light-activated NiMoO4/g-C3N4 heterojunction photocatalyst in the water environment

Semiconductor photocatalytic technology is one of the potential ways to eliminate antibiotic pollution in the water environment. In this study, NiMoO4/g-C3N4 (NMCN) heterojunction photocatalyst was fabricated via an ultrasonic-assisted hydrothermal route. The synthesized monomer and heterojunction photocatalyst samples were characterized in terms of crystal structure, elementary composition, morphology, optical properties, and so on. Upon visible light irradiation, the prepared 30NMCN sample displayed prominent photocatalytic degradation efficiency (89%) of tetracycline within 3 h, which was 1.48 and 2.02 times of NiMoO4 and g-C3N4, respectively. In addition, the 30NMCN sample showed outstanding recyclability after multiple tetracycline photocatalytic degradation processes. Ultimately, the mechanism of the enhanced tetracycline degradation performance over NMCN photocatalysts was elucidated. The meliorative photocatalytic performance was ascribed to the expansion of the light-harvesting range and the alteration of migration pathways of photogenerated charge carriers.