Highly efficient degradation of phenol from wastewater an electro-catalytic oxidation approach with a CeO-CuO cathode.

The development of highly efficient cathode materials for the electro-catalytic oxidation of phenol from wastewater is of vital importance for environment protection. Herein, we develop an effective CeO-CuO electrocatalyst for 2-electron oxygen reduction reaction (ORR) to generate HO, and then applied it as the cathode for the electro-catalytic oxidation of phenol. Results showed that the CeO-CuO cathode with different contents of CuO exhibited a higher yield of HO than those of CuO and CeO, and the highest yield of HO (114 mg L) was achieved with a CuO content of 13.4%. The resultant CeO-CuO-13.4% cathode demonstrated a high degradation rate of 91% after 180 min, which was 1.82-fold and 1.52-fold higher than pure CuO (50%) and CeO (60%) electrodes, respectively. Furthermore, the degradation rate of phenol the electro-catalytic oxidation technology by using a CeO-CuO cathode significantly outperformed that of the chemical oxidation approach. The outstanding degradation performance of the CeO-CuO cathode is attributed to the high yield of HO and the strong interaction of CeO and CuO.