Understanding photoelectrochemical degradation of methyl orange using TiO2/Ti mesh as photocathode under visible light

A better understanding of photoelectrochemical degradation of methyl orange (MO) on TiO2/Ti mesh photocathode is extremely important for improving the efficiency of dye degradation technology. The influence of morphology, crystallinity, anatase-rutile ratio and the active surface area of the photocathode have been analyzed using atomic force microscope (AFM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). CV, EIS studies along with product analysis reveal that, the photocathode calcined at 550 °C, having rutile:anatase ratio of 20:80, shows highest dye degradation because of favored catalytst morphology, enhanced adsorption of dye molecules and smallest charge-transfer resistance. The product analysis reveals that MO is degraded into simple and useful components such as hydrazine and acetic acid hydrazide.