Title: | Photoelectron Spectroscopy at the Graphene–Liquid Interface Reveals the Electronic Structure of an Electrodeposited Cobalt/Graphene Electrocatalyst |
Authors: | Juan J. Velasco-Velez;Verena Pfeifer;Michael Hävecker;Robert S. Weatherup;Rosa Arrigo;Cheng-Hao Chuang;Eugen Stotz;Gisela Weinberg;Miquel Salmeron;Robert Schlogl;and Axel Knop-Gericke |
Keywords: | electrodeposition;electrocatalysis;graphene/cobalt;photoelectron spectroscopy;X‐ray absorption spectroscopy |
Date: | 2015-10-23 |
Issue Date: | 2017-03-10 02:13:20 (UTC+8) |
Abstract: | Electrochemically grown cobalt on graphene exhibits exceptional performance as a catalyst for the oxygen evolution reaction (OER) and provides the possibility of controlling the morphology and the chemical properties during deposition. However, the detailed atomic structure of this hybrid material is not well understood. To elucidate the Co/graphene electronic structure, we have developed a flow cell closed by a graphene membrane that provides electronic and chemical information on the active surfaces under atmospheric pressure and in the presence of liquids by means of X-ray photoelectron spectroscopy (XPS). We found that cobalt is anchored on graphene via carbonyl-like species, namely Co(CO)x, promoting the reduction of Co3+ to Co2+, which is believed to be the active site of the catalyst. |
Relation: | Angewandte Chemie International Edition 54(48), p.14554-14558 |
DOI: | 10.1002/anie.201506044 全文 |
Appears in Collections: | [Graduate Institute & Department of Physics] Journal Article
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