Electrocatalytic removal of persistent organic contaminants at molybdenum doped manganese oxide coated TiO2 nanotube-based anode

Abstract

Electrooxidation is an attractive technique that can be effectively applied for the treatment of persistent organic contaminants, but its implementation in practice is limited by the lack of efficient and low-cost anode material that would not lead to the generation of chlorinated by products. Herein, we developed a novel anode based on TiO2 nanotube array (NTA) coated with Mo-doped MnxOy, and applied it for electrooxidation of persistent organic contaminants. The Ti/TiO2 NTA–MnxOy-Mo anode outperformed the commercial Ti/IrOx-Pt anode and effectively oxidized organic contaminants, with a significantly reduced electric energy per order, and avoiding chlorine evolution reaction. Mo doping played a key role in the excellent performance of the synthesized anode as it favored the formation of oxygen vacancies in the host lattice and Mn and Mo species redox couples, which increased the oxidizing power of the anode and ensured its complete stability.