Synthesis of CQDs@FeOOH nanoneedles with abundant active edges for efficient electro-catalytic degradation of levofloxacin: Degradation mechanism and toxicity assessment

Abstract

The occurrence of antibiotics in water environment has drawn great concerns in recent years. In this work, CQDs@FeOOH electro-catalyst with abundant active edges was synthesized and applied to the degradation of antibiotics. About 99.6 % levofloxacin (LEVO) and 53.7 % TOC could be efficiently removed by CQDs@FeOOH after 60 min degradation. The high LEVO degradation performance of CQDs@FeOOH was demonstrated to be attributed to the high mass transfer ability and the high OH generation ability of the special needles structure. The OH was found to be the main radical for LEVO degradation, and the highest OH generation ability of CQDs@FeOOH was found to be resulted from the moderate adsorption energy of the exposed (1 1 0) facets (needles) toward OH. A possible LEVO degradation pathway has been proposed and toxicity changes during LEVO degradation were detailed investigated. This study offers an efficient method to reduce the amount and toxicity of antibiotics in water.