Identification of Fenton-like active Cu sites by heteroatom modulation of electronic density

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 119; no. 8; pp. 1 - 8
• Main Authors: Zhou, Xiao, Huang, Gui-Xiang, Chen, Cai, Chen, Wenxing, Liang, Kuang, Qu, Yunteng, Yang, Jia, Wang, Ying, Li, Fengting, Yu, Han-Qing, Wu, Yuen
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 22.02.2022
• Subjects: Boron; Carbon sources; Catalysts; Copper; Density; Electronic structure; Electrons; Oxidation; Phosphorus; Physical Sciences; Single atom catalysts; Substrates; single-atom catalysts; Fenton-like process; reaction kinetics; heteroatom-doped engineering; electronic structure
• ISSN: 0027-8424; 1091-6490; 1091-6490
• DOI: 10.1073/pnas.2119492119

Developing heterogeneous catalysts with atomically dispersed active sites is vital to boost peroxymonosulfate (PMS) activation for Fenton-like activity, but how to controllably adjust the electronic configuration of metal centers to further improve the activation kinetics still remains a great challenge. Herein, we report a systematic investigation into heteroatom-doped engineering for tuning the electronic structure of Cu-N₄ sites by integrating electron-deficient boron (B) or electron-rich phosphorus (P) heteroatoms into carbon substrate for PMS activation. The electrondepleted Cu-N₄/C-B is found to exhibit the most active oxidation capacity among the prepared Cu-N₄ single-atom catalysts, which is at the top rankings of the Cu-based catalysts and is superior to most of the state-of-the-art heterogeneous Fenton-like catalysts. Conversely, the electron-enriched Cu-N₄/C-P induces a decrease in PMS activation. Both experimental results and theoretical simulations unravel that the long-range interaction with B atoms decreases the electronic density of Cu active sites and down-shifts the d-band center, and thereby optimizes the adsorption energy for PMS activation. This study provides an approach to finely control the electronic structure of Cu-N₄ sites at the atomic level and is expected to guide the design of smart Fenton-like catalysts.