Synergistic visible-light photocatalytic degradation of amoxicillin and ciprofloxacin using Ag/AgO-integrated 2D/2D g-C3N4/Ni3V2O8 S-scheme heterostructure

Abstract

Employing a Step-scheme (S-scheme) configuration combined with a cocatalyst offers an effective approach to boost the photocatalytic efficiency of nano-heterostructures. In this study, Ag/AgO nanoparticles were integrated into a 2D/2D heterojunction (g-C₃N₄/Ni₃V₂O₈) for the photocatalytic degradation of amoxicillin and ciprofloxacin under visible light exposure. Various comprehensive investigative techniques were utilized to verify the composition, formation, and band structure of the g-C₃N₄/Ni₃V₂O₈–Ag/AgO heterostructure. The embedded Ag/AgO nanoparticles play a dual role: capturing carriers of charge and encouraging electron-hole separation, thus creating a heterojunction of the p-n S-scheme that improves the electrons and holes redox potential for surface reactions. The 2D/2D morphology enables substantial interfacial contact, while Ag/AgO nanoparticles act as cocatalysts, improving electron extraction, affecting product selectivity, and boosting catalytic activity. The optimized g-C₃N₄/Ni₃V₂O₈–Ag/AgO composite exhibits significant photocatalytic degradation of ciprofloxacin (CIP) and amoxicillin (AMX) under the influence of visible light, reaching elimination rates of 58.8% and 62.1% within 270 min, respectively. Additionally, •O₂⁻ and h⁺ are the primary active species, with •O₂⁻ leading the photocatalytic elimination of CIP and AMX. This study highlights a potential strategy to developing photocatalysts with a high elimination efficiency of antibiotics by harnessing the enhanced reducing and oxidizing capabilities of S-scheme heterojunctions through meticulous structural configuration.