BiVO4 ternary photocatalyst co-modified with N-doped graphene nanodots and Ag nanoparticles for improved photocatalytic oxidation: A significant enhancement in photoinduced carrier separation and broad-spectrum light absorption

Abstract

The efficient removal of antibiotics in water is essential to protect aquatic environment as antibiotics are some of the most hazardous pollutants in water. Herein, we report the synthesis of a novel N-GNDs/Ag/BiVO4 ternary photocatalyst consisting of BiVO4 coupled with Ag nanoparticles (Ag-NPs) and nitrogen-doped graphene nano dots (N-GNDs) to degrade and mineralize tetracycline hydrochloride (TC center dot HCl) in water. The ternary photo catalyst shows higher photocatalytic degradation of TC center dot HCl under full spectrum light than pure BiVO4. Based on the morphology, crystalline structure, physicochemical properties, and photoelectrochemical behavior of the ternary photocatalyst, the enhanced photocatalytic performance is attributed to the upconversion effect of NGNDs and the localized surface plasmon resonance (LSPR) effect of Ag-NPs. Thus, the synergetic effects expand the absorption range of light and significantly promotes the separation of photoexcited carriers. Further, a possible photocatalytic reaction mechanism of TC center dot HCl degradation over N-GNDs/Ag/BiVO4 is discussed via through investigation of the charge carrier migration, active species, and intermediates in the degradation processes.