Single atom manganese catalyst boosting selective oxidation of alcohols with activated peroxymonosulfate

Jiaquan Li; Shiyong Zhao; Claudia Li; Sibudjing Kawi; Kai Wang; Jun Huang; Shaomin Liu

doi:10.1016/j.jcis.2023.11.076

Single atom manganese catalyst boosting selective oxidation of alcohols with activated peroxymonosulfate

J Colloid Interface Sci. 2024 Feb 15:656:58-67. doi: 10.1016/j.jcis.2023.11.076. Epub 2023 Nov 15.

Authors

Jiaquan Li¹, Shiyong Zhao², Claudia Li³, Sibudjing Kawi⁴, Kai Wang⁵, Jun Huang⁶, Shaomin Liu⁵

Affiliations

¹ School of Chemical and Biomolecular Engineering, Sydney Nano Institute, The University of Sydney, Sydney, NSW 2037, Australia.
² Australian Carbon Materials Centre (A-CMC), School of Chemical Engineering, University of New South Wales, Sydney, NSW 2052, Australia. Electronic address: shiyong.zhao@unsw.edu.au.
³ Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 119260, Singapore.
⁴ Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 119260, Singapore. Electronic address: chekawis@nus.edu.sg.
⁵ WA School of Mines: Minerals, Energy and Chemical Engineering, Curtin University, WA 6102, Australia.
⁶ School of Chemical and Biomolecular Engineering, Sydney Nano Institute, The University of Sydney, Sydney, NSW 2037, Australia. Electronic address: jun.huang@sydney.edu.au.

PMID: 37984171
DOI: 10.1016/j.jcis.2023.11.076

Abstract

Selective oxidations are important reactions in organic synthesis for fine chemical industry and conventional methods are expensive and produce a lot of toxic wastes. Herein, we demonstrate a facile and environmentally benign technique for liquid phase selective oxidation based on graphene-supported Mn single-atom-catalyst (SAMn-G) for efficient peroxymonosulfate (PMS) activation. The active Mn component in the developed SAMn-G catalyst reached single-atomic dispersion on graphene substrate via the coordination of individual Mn atoms with the doped N from the graphene framework. SAMn-G activated PMS via a nonradical-dominated pathway, which could convert aromatic alcohols into aldehydes or ketones at a mild temperature. The SAMn-G catalyst exhibited superior conversion and aldehyde selectivity in alcohol oxidation in comparison with their counterpart catalysts possessing either homogeneous Mn ions or oxide particles. The high activation efficiency of SAMn-G is due to the synergistic effect between Mn atoms and graphene substrate, as well as the dominated reaction pathway from nonradical oxidation, which is more selective than these free radicals to oxidize the alcohols. Concerted experimental evidence indicates that the non-radical oxidation process was highly possible to follow the electron transfer mechanism by PMS/organic adsorption on the surface of the catalyst. This study provides a fundamental understanding of PMS activation mediated by single atom catalyst for organic synthesis and the achieved insights can also help the catalyst design for other liquid phase selective oxidation processes.

Keywords: Manganese; Mechanism; Peroxymonosulfate; Selective oxidation; Single atom catalyst.