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Indexed by:期刊论文

Date of Publication:2018-06-29

Journal:iScience

Included Journals:PubMed

Volume:4

Page Number:144-152

ISSN No.:2589-0042

Key Words:Electrocatalysis,Energy Materials,Inorganic Chemistry,Surface Science

Abstract:Identifying surface active intermediate species is essential to reveal the catalytic mechanism of water oxidation by metal-oxides-based catalysts and to develop more efficient catalysts for oxygen-oxygen bond formation. Here we report, through electrochemical methods and ex situ infrared spectroscopy, the identification of a MnVII = O intermediate during catalytic water oxidation by a c-disordered δ-MnOx with an onset-potential-dependent reduction peak at 0.93 V and an infrared peak at 912 cm-1. This intermediate is proved to be highly reactive and much more oxidative than permanganate ion. Therefore, we propose a new catalytic mechanism for water oxidation catalyzed by Mn oxides, with involvement of the MnVII = O intermediate in a resting state and the MnIV-O-MnVII = O as a real active species for oxygen-oxygen bond formation.Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.