V2O5 nanodot-decorated laminar C3N4 for sustainable photodegradation of amoxicillin under solar light

Innovative solar-driven heterostructure photocatalysts are promising for removing deleterious antibiotics residues in the water environment. Herein, we prepared a vanadium pentoxide/graphitic carbon nitride (V2O5/C3N4) S-scheme with a facile approach. The heterostructure provides larger surface areas, promotes the separation and transfer of charge carriers, and offers abundant active sites for photocatalytic redox reactions. The composites were used to degrade amoxicillin (AMX) under solar light which attained a high removal efficiency (91.3%) and stability. Meanwhile, the photodegradation pathway of AMX was revealed by HPLC-MS/MS analysis and density functional theory (DFT) computations. Superoxide radicals evolved from conduction band of C3N4 and oxidative holes were generated from valence band of V2O5, which were confirmed by electron spin resonance experiments and selective radical quenching experiments. The V2O5/C3N4 S-scheme structure provides an internal electron channel at the interface and maintains the active sites with high potentials for photodegradation. Our work affords a robust V2O5/C3N4 S-scheme nanocomposites for sustainable water purification.