Coupling of the electrochemical oxidation (EO-BDD)/photocatalysis (TiO2-Fe-N) processes for degradation of acid blue BR dye

Abstract

We report on the successful preparation of Fe-N codoped Titania powders, using TiO2 Degussa P25, salt of Fe (II), and Urea. Modified Titania-based materials were characterized by SEM, EDS, BET, Raman, XRD diffraction and diffuse reflectance UV–vis spectroscopy measurements. The doping of TiO2 induced a shift in the absorption threshold toward the spectral range, obtaining catalysts with a greater photoactivity than the one of pure Degussa P25. The degradation of 200mL of a solution with 50mgL−1 acid blue BR dye in sulfate medium at pH3.0 has been comparatively studied by electrochemical oxidation using a boron doped diamond anode (EO-BDD), Photocatalysis TiO2-Fe-N, and coupled material of EO-BDD/Photocatalysis TiO2-Fe-N. The solution was slowly degraded by EO-BDD (25%) and single Photocatalysis TiO2-Fe-N because of the low rate of dye degradation and its colored by-products with hydroxyl radicals generated at the BDD anode and catalyst surface from water oxidation (29%), whereas the solution was more rapidly degraded using coupled material of EO-BDD/Photocatalysis TiO2-Fe-N (82%), owing to the additional generation of hydroxyl radicals from the photocatalysis of TiO2-Fe-N and BDD anode.