Electrocatalytic degradation of methylene blue on Co doped Ti/TiO2 nanotube/PbO2 anodes prepared by pulse electrodeposition

Co doped Ti/TiO2 nanotube/PbO2 (TiO2-NTs/Co-PbO2) was prepared by a pulse electrodeposition technique for methylene blue (MB) degradation. The TiO2-NTs/Co-PbO2 electrode was characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The results indicated that TiO2-NTs/Co-PbO2 electrodes (P) prepared by the pulse electrodeposition technique possess a more compact structure and finer grain size than TiO2-NTs/Co-PbO2 electrodes (D) prepared by direct electrodeposition. The electrochemical properties of electrodes were studied by steady-state polarization curves, cyclic voltammetry (CV) and eletrochemical impendence spectroscopy (EIS). The electrochemical measurements also demonstrate that TiO2-NTs/Co-PbO2 electrodes (P) have more excellent direct electrochemical oxidation performance. The electrocatalytic property of TiO2-NTs/Co-PbO2 electrodes was also examined for the electrochemical oxidation of methylene blue (MB). Bulk electrolysis showed that the methylene blue (MB) and chemical oxygen demand (COD) removal efficiency of TiO2-NTs/Co-PbO2 electrodes (P) reach 100% and 74.0% respectively after 120 min. The experimental results demonstrate that the TiO2-NTs/Co-PbO2 electrode (P) is a promising material for the treatment of organic pollutants.