E-Waste Based V₂O₅/RGO/Pt Nanocomposite for Photocatalytic Degradation of Oxytetracycline

The increasing prevalence of antibiotics in the environment has promoted the development of antibiotic resistant microorganisms, and novel approaches are needed to effectively remove antibiotics from water and mitigate this worldwide problem. A reduced graphene oxide-V₂O₅ (RGOV) nanocomposite was synthesized and used for photocatalytic degradation of the antibiotic oxytetracycline (OTC) in aqueous solution. The Sol–Gel method was employed for V₂O₅ synthesis from e-waste-based vanadium nitrate, and a one pot solvothermal method was used to synthesize RGOV. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM) with energy dispersive analysis of X-rays (EDAX) confirmed V-O-C bonds on the surface of the RGOV nanocomposites. A decrease in the band gap of V₂O₅ from 2.21 to 2.13 eV was supported by diffuse reflectance ultraviolet–visible spectrophotometry. OTC adsorption onto the nanocomposite increased with an increase in RGO concentration and saturated at 17% for RGOV with 30% graphene oxide. The composite degraded 90% of the OTC present in aqueous solution (50 mg/L). Platinum (1%) doping further increased OTC degradation by the nanocomposite to 98.7%. Optimum conditions for maximum OTC degradation are (1) an initial OTC concentration of 50 mg/L, (2) a RGOV nanocomposite dose of 0.5 g/L, and (3) a 40 min incubation time. Our results support the potential use of RGOV nanocomposite for OTC photodegradation.