Electrocatalytic Degradation of Azo Dye by Vanadium-Doped TiO2 Nanocatalyst.

In this work, nano V/TiO₂ catalysts at different molar ratios were prepared and fabricated as the electrocatalytic electrodes for electrocatalytic degradation. The effect of the vanadium doping on the surface morphology, microstructural, and specific surface area of V/TiO₂ catalysts was probed by field emission scanning electron microscope (FESEM) x-ray diffractometer (XRD), and Brunauer–Emmett–Teller (BET), respectively. Afterward, the solution of Acid Red 27 (AR 27, one kind of azo dye) was treated by an electrocatalytic system in which the nano V/TiO₂ electrode was employed as the anode and graphite as the cathode. Results demonstrate that AR 27 can be effectively degraded by the nano V/TiO₂ electrodes; the highest removal efficiency of color and total organic carbon (TOC) reached 99% and 76%, respectively, under 0.10 VT (molar ratio of vanadium to titanium) condition. The nano V/TiO₂ electrode with high specific surface area facilitated the electrocatalytic degradation. The current density of 25 mA cm⁻² was found to be the optimum operation for this electrocatalytic system whereas the oxygen was increased with the current density. The electricity consumption of pure TiO₂ and nano V/TiO₂ electrode in this electrocatalytic system was around 0.11 kWh L⁻¹ and 0.02 kWh L⁻¹, respectively. This implies that the nano V/TiO₂ electrode possesses both high degradation and energy saving features. Moreover, the nono V/TiO₂ electrode shows its possible repeated utilization. [ABSTRACT FROM AUTHOR]