Oxygen vacancy enhancing the Co3O4-CeO2 nanosheets as the cathode to activate peroxymonosulfate for degradation of ceftiofur sodium

Herein, the bimetallic oxides Co3O4-CeO2 with abundant oxygen vacancy (VO) were successfully prepared and applied to activate peroxymonosulfate (PMS) for degradation of ceftiofur sodium (CEF). By optimizing the molar ratio of Co and Ce, nanosheet structures were obtained, which had large surface area and rich oxygen vacancies. The degradation efficiency of CEF can reach 94.3 % and the corresponding TOC removal is as high as 50.3 % after 40 min under the optimum conditions with 10 mA−1 cm−2 current density, pH 3, 5 mM PMS and 25 ℃. 1O2 is the main reactive species and its formation is related with VO in the process of degradation CEF. In details, the abundant VO on the catalyst surface can not only accelerate electron transfer to promote the conversion of PMS → ·SO5-· → 1O2 but also act as electron transport channels to facilitate Co3+/Co2+ redox cycle. This study is of far-reaching significance for oxygen vacancy-activated PMS to promote the efficient degradation of refractory organic pollutants.