Ultrastable cobalt-based chainmail catalyst for degradation of emerging contaminants in water

Developing stable and efficient cobalt-based catalysts for degradation of emerging contaminants (ECs) in water is deemed as a practical strategy to avoid secondary pollution in advanced oxidation processes (AOPs). Herein, we developed a ultrastable cobalt-based chainmail catalysts (Co-NC900) using 2, 2'-bipyridine-assistant pyrolysis method. More than 96.6 % of imidacloprid (IMD) in water could be degraded within 5 min in the presence of Co-NC900 and peroxymonosulfate (PMS). Amazingly, Co-NC900 still give 95 % degradation efficacy for IMD after15 runs. And only 0.083 mu g L-1 of Co could be detected in the reaction mixture after continuous using 7 d. Density Functional Theory (DFT) calculations demonstrated that Co-NC900 can efficiently activate PMS through unique ping-pong mechanism (C-N bond breaking and re-forming process), and further degrade ECs. This study presents a novel approach for the development of efficient and stable metal-based catalysts for the removal of ECs from water.