Mechanism and Performance of Electrocatalytic Oxidation on RuO-IrO@Ti Anode in Alkaline Phenol Wastewater.

Phenol, a highly biotoxic organic pollutant, is widely present in alkaline wastewater from industries such as petrochemical and coking plants. However, its efficient degradation remains challenging with existing technologies. In this study, a RuO-IrO@Ti electrode was fabricated by a coating method, achieving an oxygen evolution potential of 2.0 V vs RHE (Reversible Hydrogen Electrode). Under alkaline conditions (pH = 10) with optimized operating parameters (38 mA/cm current density and 0.25 M NaCl electrolyte), the degradation efficiency of 125 mg/L phenol reached 92.33% within 180 min. Mechanistic investigations, including radical quenching experiments, GC-MS analysis of intermediates, and Fukui function-based reactive site analysis, confirmed that indirect oxidation dominated the degradation process. The primary degradation pathway involved electrophilic substitution by ClO, synergistically enhanced by oxidation via superoxide radicals (O ). The electrode exhibited outstanding stability, maintaining a degradation efficiency of 90% after 30 consecutive cycles, while the electrochemically active surface area (ECSA) increased from 0.17 cm to 0.44 cm, demonstrating its potential for industrial applications.