Photoelectron spectroscopy at the graphene–liquid interface reveals the electronic structure of an electrodeposited cobalt/graphene electrocatalyst

DOI: 10.1002/anie.201506044
PMID: 26463455

Authors: Juan J. Velasco-Velez (Max Planck Institute) , Verena Pfeifer (Fritz-Haber-Institut der Max-Planck-Gesellschaft) , Michael Hävecker (Max Planck Institute) , Robert S. Weatherup (Lawrence Berkeley National Laboratory) , Rosa Arrigo (Diamond Light Source) , Cheng-Hao Chuang (Tamkang University) , Eugen Stotz (Fritz-Haber-Institut der Max-Planck-Gesellschaft) , Gisela Weinberg (Fritz-Haber-Institut der Max-Planck-Gesellschaft) , Miquel Salmeron (Lawrence Berkeley National Laboratory) , Robert Schlögl (Fritz-Haber-Institut der Max-Planck-Gesellschaft) , Axel Knop-Gericke (Fritz-Haber-Institut der Max-Planck-Gesellschaft)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Angewandte Chemie International Edition , VOL 54 (48) , PAGES 14554 - 14558

State: Published (Approved)
Published: November 2015

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.

Journal Keywords: Electrocatalysis; Electrodeposition; Graphene; Cobalt; Photoelectron Spectroscopy; X-Ray Absorption; Spectroscopy

Subject Areas: Chemistry, Energy, Materials

Facility: ISISS at BESSY II

Added On: 06/01/2016 12:05

Discipline Tags:

Earth Sciences & Environment Sustainable Energy Systems Energy Climate Change Physical Chemistry Catalysis Energy Materials Chemistry Materials Science

Technical Tags: