Journal Article

Regulating the coordination structure of single-atom Fe-NxCy catalytic sites for benzene oxidation

Liu, Chenguang, Zheng, Lirong, Meng, Tao, Peng, Qing, Wang, Dingsheng, Chen, Zheng, Chen, Yinjuan, Liu, Shoujie, Wu, Konglin, Li, Jun, Luo, Jun, Chen, Chen, Cheong, Weng-Chon, Pan, Yuan, Cao, Xing

2019

Overview

Atomically dispersed metal-N-C structures are efficient active sites for catalyzing benzene oxidation reaction (BOR). However, the roles of N and C atoms are still unclear. We report a polymerization-regulated pyrolysis strategy for synthesizing single-atom Fe-based catalysts, and present a systematic study on the coordination effect of Fe-N x C y catalytic sites in BOR. The special coordination environment of single-atom Fe sites brings a surprising discovery: Fe atoms anchored by four-coordinating N atoms exhibit the highest BOR performance with benzene conversion of 78.4% and phenol selectivity of 100%. Upon replacing coordinated N atoms by one or two C atoms, the BOR activities decrease gradually. Theoretical calculations demonstrate the coordination pattern influences not only the structure and electronic features, but also the catalytic reaction pathway and the formation of key oxidative species. The increase of Fe-N coordination number facilitates the generation and activation of the crucial intermediate O=Fe=O species, thereby enhancing the BOR activity. Atomically dispersed metal-N-C are efficient active site for benzene oxidation but the roles of N and C atoms are still unclear. Here the authors report a highly-active single-atom Fe-based benzene oxidation catalyst and provide deep insights into the structure-activity relationship at atomic level.

• Publisher: Nature Publishing Group UK
• Subject: 119/118 / 140/146 / 147/143 / 639/638/77/885 / 639/638/77/887 / 639/925/357/551 / Humanities and Social Sciences / multidisciplinary / Science / Science (multidisciplinary)