Nitrogen-Coordinated Cobalt Embedded in a Hollow Carbon Polyhedron for Superior Catalytic Oxidation of Organic Contaminants with Peroxymonosulfate
Nitrogen-Coordinated Cobalt Embedded in a Hollow Carbon Polyhedron for Superior Catalytic Oxidation of Organic Contaminants with Peroxymonosulfate
复制标题
嵌入中空碳多面体中的氮配位钴可用于过一硫酸盐对有机污染物的出色催化氧化
DOI：
10.1021/acsestengg.0c00039
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发表时间：
2021-01-08
影响因子：
7.1
通讯作者：
Hu, Chun
中科院分区：
文献类型：
--
作者：
Gao, Yaowen;Zhu, Yue;Hu, Chun
寻找高效、耐久的材料对去除水中有机污染物具有重要意义。本文采用核壳结构的ZIF-8@ZIF-67的热转化方法合成了一种嵌于中空碳多面体中的氮配位钴(标记为NCoHCP)。X射线光电子能谱(XPS)、X射线吸收光谱(XAS)和理论计算证实了NCoHCP中一个Co原子与一个N原子的配位。实验数据和理论计算表明，Co-吡啶基N部分的形成不仅产生了具有较高电子密度的Co物种作为活性中心，而且增加了与具有较低电子密度的吡啶N相邻的C原子作为PMS的结合中心，从而使PMS转化为活性氧物种，从而氧化有机污染物。另一方面，有机污染物向毗邻吡啶N的C原子提供电子也会引起有机污染物的氧化。NCoHCP对有机物的催化氧化作用优于NCoHCP。这项研究为开发面向广泛环境应用的高性能和坚固的金属/碳杂化材料提供了一种有效的策略。
The search for high-active and long-lasting materials is of paramount significance for elimination of aqueous organic contaminants. Herein, a nitrogen-coordinated cobalt embedded in hollow carbon polyhedron (marked as NCoHCP) has been synthesized by thermal transformation of core-shell-architectured ZIF-8@ZIF-67. X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), and theoretical calculations confirmed the coordination of a Co atom with one N atom in NCoHCP. The resultant NCoHCP catalyst delivers extremely superior catalytic performance in peroxymonosulfate (PMS) decomposition into active species toward complete oxidation of organic pollutants in less than 45 s. Experimental data and theoretical computations disclosed the formation of Co-pyridinic N moiety not only creates the Co species with higher electron density as active sites but also increases the C atom neighboring pyridinic N with lower electron density as binding sites for PMS conversion toward reactive oxygen species generation to oxidize organic pollutant. On the other hand, the donation of electron from organic contaminant toward the C atom adjacent to pyridinic N also induces organic contaminant oxidation. The dual-pathway degradation contributes to superior catalytic oxidation of organics over NCoHCP. This study furnishes an effective strategy for developing high-performance and robust metal/carbon hybrid materials toward wide environmental applications.