Fabrication of Ru/Ir doped TiO₂ electrode for electrocatalytic degradation of phenol

Abstract

Electrocatalytic oxidation technology has been proved as an efficient method for degradation in organic wastewater. The service lifetime and degradation efficiency of the electrode, one crucial struggle, limits the broad application of electrocatalytic oxidation technology. Herein, a Ru/Ir doped TiO2 electrode with a long service lifetime was developed. Accelerated life experiment showed that the service life of an electrode was 33 h when the concentration of sulfuric acid was 1 M and the current density was 2000 mA·cm−2. The influence on the phenol degradation was evaluated by researching the operating parameters. In particular, the possible mechanism of phenol removal at different pH is elucidated. It is found that acidic environment is favorable for chemical oxygen demand (COD) and phenol removal at a current density of 20 mA·cm−2, pH 3 at 800 ppm NaCl, which can make the removal rates of phenol and COD with Ru/Ir doped TiO2 anode up to 97.21% and 100%. In addition, it was demonstrated that the hydroxyl radicals play a foremost role in the degradation of phenol. Given the well stability and high service life, the Ru/Ir doped TiO2 electrode holds promise for further industrial application in wastewater treatment.