Photocatalytic degradation of levofloxacin by GO-TiO2 under visible light

Abstract

The utilisation of graphene oxide (GO)-modified titanium dioxide (TiO2) for the photocatalytic degradation of levofloxacin (LEV) under visible light exposure represents a promising solution for mitigating the growing concern surrounding pharmaceutical contaminants in water bodies. Levofloxacin, a commonly used antibiotic, has been detected in aquatic environments, raising ecological and human health apprehensions due to its potential to foster antibiotic resistance and provoke adverse effects. A carbon-doped titanium dioxide catalyst was synthesised via the sol–gel method by introducing graphene oxide. Various characterization techniques were employed to assess the resulting catalyst, including XRD, FTIR, BET, DLS, CHNS, and UV–vis. The doping process significantly increased the catalyst's surface area and enhanced its capacity to absorb visible light. Photocatalytic experiments demonstrated that the degradation of levofloxacin followed pseudo-first-order kinetics and adhered to the Langmuir-Hinshelwood model. Specifically, the doped catalyst containing approximately 3 % carbon achieved an impressive 74 % degradation of levofloxacin within a mere 3-hour exposure to visible light (LED), with a rate constant of roughly 0.015 min−1. This approach holds great potential for combatting the persistent problem of antibiotic contamination in water, thereby promoting the sustainability and safety of aquatic ecosystems and human well-being. Further investigation is essential to assess this innovative photocatalytic technology's practical applicability and scalability in real-world scenarios.