Precise coordination of high-loading Fe single atoms with sulfur boosts selective generation of nonradicals

• 成果类型: Article
• 署名作者: Jiang, Xunheng; Zhou, Binghui; Yang, Weijie; Chen, Jiayi; Miao, Chen; Guo, Zhongyuan; Li, Hao; Hou, Yang; Xu, Xinhua; Zhu, Lizhong; Lin, Daohui; Xu, Jiang
• 署名单位: Zhejiang University; North China Electric Power University; Zhejiang University; Tohoku University; Zhejiang University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12850
• DOI: 10.1073/pnas.2309102121
• 发表日期: 2024-01-23
• 关键词: peroxymonosulfate; catalysts; EVOLUTION; sites

摘要

Nonradicals are effective in selectively degrading electron-rich organic contaminants, which unfortunately suffer from unsatisfactory yield and uncontrollable composition due to the competitive generation of radicals. Herein, we precisely construct a local microenvironment of the carbon nitride-supported high-loading (similar to 9 wt.%) Fe single-atom catalyst (Fe SAC) with sulfur via a facile supermolecular self-assembly strategy. Short-distance S coordination boosts the peroxymonosulfate (PMS) activation and selectively generates high-valent iron-oxo species (Fe-IV=O) along with singlet oxygen (O-1(2)), significantly increasing the O-1(2) yield, PMS utilization, and p-chlorophenol reactivity by 6.0, 3.0, and 8.4 times, respectively. The composition of nonradicals is controllable by simply changing the S content. In contrast, long-distance S coordination generates both radicals and nonradicals, and could not promote reactivity. Experimental and theoretical analyses suggest that the short-distance S upshifts the d-band center of the Fe atom, i.e., being close to the Fermi level, which changes the binding mode between the Fe atom and O site of PMS to selectively generate O-1(2) and Fe-IV=O with a high yield. The short-distance S-coordinated Fe SAC exhibits excellent application potential in various water matrices. These findings can guide the rational design of robust SACs toward a selective and controllable generation of nonradicals with high yield and PMS utilization.