Carbon nitride quantum dots control RuO2-TiO2/Ti coated anodes for degradation of high concentration phenol

In this study, nitrogen-doped carbon quantum dots (N-CQDs) were fabricated by a one-step hydrothermal method , and RuO 2 -TiO 2 -N-CQDs/Ti composite-coated anodes were fabricated using a sol-gel method. The results indicate that the doping of N-CQDs generates many vacancy defects on the surface of the composite coating . As the content of N-CQDs increases, the width and depth of surface cracks on the coating gradually decrease, and the crystal size decreases. The doping of N-CQDs can effectively improve the electrochemical performance of the anode. When the doping amount of N-CQDs is 9.7 %, the surface charge capacity is increased by 243.5 %, the polarisation potential is decreased by 160 mV, and the self-corrosion potential is increased by 87.1 %. Compared to the traditional RuO 2 -TiO 2 /Ti anode, when the content of N-CQDs is increased to 9.7 %, the removal efficiency of phenol on the RuO 2 -TiO 2 -N-CQDs/Ti composite-coated electrode is increased by 93.2 %. In comparison, the removal efficiency of chemical oxygen demand within 1 h is increased by 48.7 %. In this study, we fully utilised the effective electron transfer and structural changes induced by N element doping to improve the electrocatalytic performance of the electrode, providing a new approach for mineralising high-concentration phenol in Ru/Ti electrodes.