Hydrothermal Synthesis of Graphene and Titanium Dioxide Nanotubes by a One-Step Method for the Photocatalytic Degradation of Amoxicillin

To improve the photocatalytic efficiency of titanium nanotubes (TNTs) for amoxicillin removal, we synthesized a composite catalyst, graphene (GN)-TNTs through an easy one-step hydrothermal method. Photocatalytic activity for amoxicillin (AMX) degradation was studied researched under near-ultraviolet light (365 nm). The effects of GN loading, catalyst concentration, AMX concentration, and pH on photocatalytic activity were explored. Results showed that the photocatalytic activity of GN-TNT was closely related to GN loading. The degradation efficiency of AMX can reach up to 95% within 3 h with 0.1 g/L 10% GN-TNT at pH 9. Furthermore, kinetic-study results showed that degradation can be expressed by a first-order-reaction kinetic model. This study also discussed the degradation mechanism of photocatalytic activity. By adding different capture agents, the electronhole acted as the main active substance during photocatalytic degradation activity.