Modified carbon felt made using Ce(x)A(1-x)O(2) composites as a cathode in electro-Fenton system to degrade ciprofloxacin

摘要

Carbon felt (CF) was modified by Ce(x)A(1-x)O(2) (A = Zr, Cu and Ni) and the role of these Ce(x)A(1-x)O(2)CF (A = Zr, Cu and Ni) cathode materials in the oxidative degradation of antibiotic ciprofloxacin (CIP) was investigated in the electro-Fenton system. SEM, BET, TEM, XPS, TOC, HPLC-MS, CV and EIS were used to understand the characteristics of these cathode materials. The CIP degradation efficiency of the Ce(x)A(1-x)O(2)/CF (A = Zr, Cu and Ni) cathode was better than that of pure CF, and 2.0 wt% Ce0.75Zr0.25O2/CF was the most effective cathode material for degradation of CIP. It reached 100% degradation efficiency of CIP after 1 h and almost total mineralization (97.45%) after 6 h, owing to synergistic effects from the predominant role of homogeneous (OH)-O-center dot produced electrocatalytically through the Fenton reaction of Fe2+ and H2O2 and heterogeneous (OH)-O-center dot produced via the Fenton-like reaction of Ce3+ and H2O2 and the electrocatalytic activity of Ce0.75Zr0.25O2 composite and the strong electrosorption of carbon felt. A possible path of CIP degradation was proposed in the paper.