B4C/Ce co-modified Ti/PbO2 dimensionally stable anode: Facile one-step electrodeposition preparation and highly efficient electrocatalytic degradation of tetracycline

Abstract

The application of PbO2 for electrochemical oxidation technology is limited by its low electrocatalytic activity and short service life. Herein, based on the facile one-step electrodeposition, we prepared a boron carbide (B4C) and cerium (Ce) co-modified Ti/PbO2 (Ti/PbO2–B4C–Ce) electrode to overcome these shortcomings. Compared with Ti/PbO2 electrode, the denser surface is displayed by Ti/PbO2–B4C–Ce electrode. Meanwhile, electrochemical characterization indicates that the introduction of B4C and Ce significantly enhance the electrochemical performance of PbO2 electrode. In degradation experiments, under optimized conditions (current density 20 mA cm−2, pH 9, 0.15 M Na2SO4 and 30 °C), the fully degradation of tetracycline (TC) can be completed within 30 min. Furthermore, the trapping experiment demonstrates that ∙OH and SO4·- radicals have a synergistic effect in the degradation process of TC. Based on results of liquid chromatography-mass spectrometer, the generated ·OH preferentially attacks amides, phenols and conjugated double bond groups in TC. Importantly, Ti/PbO2–B4C–Ce electrode maintains a constant degradation efficiency even after 10 recycling tests, and its service life is 2.4 times of traditional Ti/PbO2 electrode. Hence, Ti/PbO2–B4C–Ce electrode is a promising electrode for degradation of organic wastewater containing amides, phenols, and conjugated double bond groups.