Unveiling the metallic size effect on O2 adsorption and activation for enhanced electro-Fenton degradation of aromatic compounds

Yanchi Yao; Jingyi Yang; Chao Zhu; Lun Lu; Qile Fang; Chao Xu; Zhiqiao He; Shuang Song; Yi Shen

doi:10.1016/j.jhazmat.2023.132739

Unveiling the metallic size effect on O2 adsorption and activation for enhanced electro-Fenton degradation of aromatic compounds

J Hazard Mater. 2024 Jan 15:462:132739. doi: 10.1016/j.jhazmat.2023.132739. Epub 2023 Oct 6.

Authors

Yanchi Yao¹, Jingyi Yang¹, Chao Zhu¹, Lun Lu², Qile Fang³, Chao Xu¹, Zhiqiao He¹, Shuang Song¹, Yi Shen⁴

Affiliations

¹ Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China.
² State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510655, PR China.
³ Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai 519087, PR China.
⁴ Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China. Electronic address: shenyi@zjut.edu.cn.

PMID: 37856960
DOI: 10.1016/j.jhazmat.2023.132739

Abstract

Metal-atom-modified nitrogen-doped carbon materials (M-N-C) have emerged as promising candidates for electro-Fenton degradation of pollutants. Nonetheless, a comprehensive exploration of size-dependent M-N-C catalysts in the electro-Fenton process remains limited, posing challenges in designing surface-anchored metal species with precise sizes. Herein, a heterogeneous-homogeneous coupled electro-Fenton (HHC-EF) system was designed and various M-N-C catalysts anchored with Co single atoms (CoSA-N-C), Co clusters (CoAC-N-C), and Co nanoparticles (CoNP-N-C) were successfully synthesized and employed in an HHC-EF system. Intriguingly, CoAC-N-C achieved outstanding removal efficiencies of 99.9% for BPA and RhB within 10 and 15 min, respectively, with the fastest reaction kinetics (0.70 min^-1 for BPA and 0.34 min^-1 for RhB). Electron spin resonance and trapping experiments revealed that·OH played a crucial role in the HHC-EF process. Moreover, experiments and theoretical calculations revealed that the unique metallic size effect facilitate the in-situ electro-generation of H₂O₂. Specifically, the atomic interaction between neighboring Co atoms in clusters enhanced O₂ adsorption and activation by strengthening the Co-N bond and transforming O₂ adsorption configuration to the Yeager-type. This study provides valuable insights that could inspire the size-oriented metal-based catalyst design from the perspective of the potential atomic distance effect.

Keywords: Carbon-based catalysts; Co clusters; Electro-Fenton; Hydroxyl radicals; Metallic size effect.