Chao Jiayu, Yang Xiaoling, Zhu Yihua, Shen Jianhua
Shanghai Engineering Research Centre of Hierarchical Nanomaterials, Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
Shanghai Engineering Research Centre of Hierarchical Nanomaterials, Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
J Colloid Interface Sci. 2024 Nov;673:434-443. doi: 10.1016/j.jcis.2024.06.035. Epub 2024 Jun 6.
Electro-Fenton is an effective process for degrading hard-to-degrade organic pollutants, such as tetracycline (TC). However, the degradation efficiency of this process is limited by the activity and stability of the cathode catalyst. Herein, a temperature gradient pyrolysis strategy and oxidation treatment is proposed to modulate the coordination environment to prepare oxygen-doped cobalt monoatomic electrocatalysts (CoNOC). The CoNOC catalysts can achieve the selectivity of 93 % for HO with an electron transfer number close to 2. In the H-cell, the prepared electrocatalysts can achieve more than 100 h of HO production with good stability and the yield of 1.41 mol g h with an average Faraday efficiency (FE) of more than 88 %. The calculations indicate that the epoxy groups play a crucial role in modulating the oxygen reduction pathway. The O doping and unique N coordination of Co single-atom active sites (CoNNO) can effectively weaken the O/OOH* interaction, thereby promoting the production of HO. Finally, the electro-Fenton system could achieve a TC degradation rate of 94.9 % for 120 min with a mineralization efficiency of 87.8 % for 180 min, which provides a reliable option for antibiotic treatment. The significant involvement of OH in the electro-Fenton process was confirmed, and the plausible mineralization pathway for TC was proposed.
电芬顿是一种降解难降解有机污染物（如四环素，简称TC）的有效方法。然而，该方法的降解效率受阴极催化剂活性和稳定性的限制。在此，我们提出一种温度梯度热解策略和氧化处理方法来调节配位环境，以制备氧掺杂钴单原子电催化剂（CoNOC）。CoNOC催化剂能够以接近2的电子转移数实现对羟基自由基（HO）93%的选择性。在H型电解槽中，所制备的电催化剂能够稳定产生HO超过100小时，产率为1.41摩尔每克每小时，平均法拉第效率（FE）超过88%。计算结果表明，环氧基团在调节氧还原途径中起着关键作用。钴单原子活性位点（CoNNO）的氧掺杂和独特的氮配位能够有效减弱O/OOH*相互作用，从而促进HO的产生。最后，电芬顿体系在120分钟内对TC的降解率可达94.9%，180分钟内矿化效率可达87.8%，为抗生素处理提供了可靠选择。证实了羟基自由基（OH）在电芬顿过程中的重要作用，并提出了TC可能的矿化途径。
