A promising electrode material modified by Nb-doped TiO2 nanotubes for electrochemical degradation of AR 73

A distinctive SnO2Sb electrode with highly ordered Nb doped TiO2 nanotubes sheet as a new substrate, obtained by NbTi alloy anodization, is prepared by pulse electrochemical deposition for the first time as electrocatalytic oxidation anode for wastewater treatment. The novel electrode has a larger surface area and smaller crystallite particles than conventional SnO2Sb electrodes as obtained from the analysis of scanning electron microscopy and X-ray diffraction. Compared with Ti/SnO2Sb and Ti/TiO2-NTs/SnO2Sb prepared by pulse electrochemical deposition, the electrode modified by NbTiO2-NTs has the higher oxygen evolution potential of 2.29 V (vs. Ag/AgCl), and the lower charge transfer resistance, which decreased by 65% and 79%. The service lifetime of NbTi/NbTiO2-NTs/SnO2Sb is 4.9 times longer than that of Ti/SnO2Sb and 1.9 times longer than that of Ti/TiO2-NTs/SnO2Sb. The new electrode is proved to have an excellent electrochemical oxidation and degradation ability using Acid Red 73 as a target organic pollutant. The AR 73 removal, chemical oxygen demand removal and kinetic rate constant are increased obviously due to the introduction of NbTiO2-NTs. Besides, the energy consumption reduces 37.2% and 31.4% in contrast with Ti/SnO2Sb and Ti/TiO2-NTs/SnO2Sb. Hence, the Ti/SnO2Sb modified by NbTiO2-NTs is a very promising anode material for the electrochemical treatment of dye wastewater. •The new substrate is of highly ordered Nb doped TiO2 nanotubes array formed by NbTi alloy anodization.•A novel SnO2Sb electrode was successfully prepared by pulse electrochemical deposition.•The novel electrode exhibited excellent electrochemical performance, electro-catalytic oxidation ability and stability.•The energy consumption was decreased obviously owing to the good conductivity and high electro-catalytic efficiency.