KBrO3 and graphene as double and enhanced collaborative catalysts for the photocatalytic degradation of amoxicillin by UVA/TiO2 nanotube processes

In this study, we found a novel property of graphene and KBrO3 as double and enhanced collaborative catalysts to degrade amoxicillin (AMX) on the photocatalytic behavior of TiO2 nanotubes under UVA light irradiation. The synthesis of graphene-TiO2 nanotubes (GN-TNT) is a necessary first step. AMX can be photo-degraded with GN-TNT, but its degradation rate reaches nearly 100% with the addition of KBrO3, which has two roles in photo-degradation. Its first and more important function is the prevention of electron-hole recombination by acting as electron acceptor. Its second function is its direct participation as oxidant in the degradation of AMX. The effects of GN loading, KBrO3 initial concentration, and AMX concentration on photocatalytic activity are explored in this study. Results of the kinetic study also show that degradation can be expressed by a first-order reaction kinetic model. The degradation mechanism of photocatalytic activity and the role of KBrO3 are also discussed.