Novel degradation of amoxicillin by WO3/Ag3VO4 Z-scheme heterojunction deposited on rGO

Abstract

In this work, Ag3VO4 was successfully hybridized with WO3 to form Ag3VO4/WO3 (AW) Z scheme heterojunction. Then, rGO was used as a substrate for deposition of the synthesized AW to further improve its electron-hole separation efficiency and surface area. The synthesized AW deposited on rGO (AW/rGO) was used for degradation residual amoxicillin upon visible light excitation. The synthesized samples were deeply characterized by XRD, HR-TEM, BET, UV–Vis, PL and Mott–Schottky plots. Scavenger experiments were also conducted to investigate photocatalytic mechanism. The obtained results indicated well hybridizing and matching band potentials between Ag3VO4 and WO3. Thus, the photo-excited electrons (e−) at WO3 conduction band (CB) would be transported from boundary to Ag3VO4 valence band (VB) and combined with its holes (h+) to inhibit charge recombination in each material resulting in accumulation of huge amounts of available e− at Ag3VO4 CB and h+ in WO3 VB. The generated e− and h+, which were high redox potentials, effectively participated in degradation of amoxicillin. The used rGO effectively increased surface area for amoxicillin adsorption and electron transfer for charge separation of the AW. Thus, the synthesized AW/rGO sample exhibited novel amoxicillin photocatalytic degradation. Finally, the regenerating experiment results indicated novel recycling ability of the AW/rGO photocatalyst.