Evaluation of the photocatalytic activity of ZnFe2O4-TiO2 composite coating elaborated by flame spraying process

Among various techniques which have been used for degradation of chemical pollutants, advanced oxidation processes (such as photocatalytic process) have received attention due to their specific properties. In this investigation, ZnFe2O4-10wt% TiO2 composite film was elaborated using flame spraying process. Powders of titania (TiO2: 75vol. % anatase, 25vol. % rutile) and zinc ferrite (ZnFe2O4), which was synthesized by mechanical alloying process, were mixed together (weight ratio of 1:9) and deposited on stainless steel 316 substrate. In order to evaluate the structure, morphology, and photo-adsorption ability of the coating, X-ray diffractometer (XRD), scanning electron microscopy (SEM), and UV-VIS-NIR spectroscopy were used, respectively. Photocatalytic performance of the deposited film was studied by bleaching of aquatic methylene blue solution with the concentration of 5 mg/Lit. The results showed that the composite coating, which was elaborated by flame spraying, possesses relatively good photo-adsorption ability as well as photocatalytic activity for photodegradation of methylene blue (under visible light irradiation).