Emerging contaminants mineralization by a photo-electrochemical method based on WO3

Abstract

WO3 absorbs light up to 470 nm and when illuminated in the presence of water generates OH• radicals, which promote oxidation of organic pollutants, such as drugs. In the case of WO3 photoanodes, a considerable acceleration (4–5 times) of degradation kinetics is obtained through the application of a 1.5 V potential bias, which is instrumental to optimize the charge separation within the films and to maximize holes transfer rate to the electrolyte. Moreover, after sufficiently long irradiation, complete mineralization of the organics is achieved. Photoelectrocatalysis is observed even in diluted supporting electrolyte conditions, representing the average salinity of natural freshwater samples, demonstrating the practical feasibility of this approach.