Enhanced photocatalytic degradation of ofloxacin by co-doped titanium dioxide under solar irradiation

摘要

The photocatalytic degradation of Ofloxacin (OFL) was studied in aqueous solution using co-doped TiO2 nanoparticles. The catalyst samples were synthesized by sol-gel method from Titanium isopropoxide using different concentration of Bi and Ni metal as dopant. The co-doped catalysts were characterized by (X-ray Diffraction) XRD, (Brunauer-Emmett-Teller) BET, (Scanning electron microscope) SEM and (Energy Dispersive Spectroscopy) EDS. The results revealed that the catalyst possessed spherical morphology and excellent crystalline properties. The surface area of the catalyst was found to be 74, 55 and 18.66 m(2)/g for 0.25 wt%, 0.5 wt% and 1.0 wt% dopant concentration, respectively. Photocatalytic capability of Bi/Ni co-doped TiO2 nanoparticles were estimated by means of OFL degradation under different light sources. Parameters affecting the photocatalytic process such as type of catalyst, dopant concentration, catalyst concentration, different light sources and solution pH have been explored. The photo degradation kinetics follows a pseudo first-order reaction. Bi-Ni co-doped TiO2 showed higher activity for photocatalytic degradation of OFL under solar light compared to Degussa TiO2. The photo-degradation process was optimized using 25 mg/L Ofloxacin with dopant concentration of 0.25 wt% and catalyst dose of 1.5 g/L. Degradation efficiency of 86% was attained at pH 3 after 6 h of solar irradiations. (C) 2016 Elsevier B.V. All rights reserved.