Jump to main content
Jump to site search

Issue 15, 2017
Previous Article Next Article

Three dimensionally ordered mesoporous hydroxylated NixCo3−xO4 spinels for the oxygen evolution reaction: on the hydroxyl-induced surface restructuring effect

Author affiliations

Abstract

Surface restructuration upon potential cycling of three dimensionally ordered NixCo3−xO4 spinels for the oxygen evolution reaction (OER) in an alkaline medium is studied using structural, spectroscopic and electrochemical techniques. It was shown that the intrinsic activity of different catalysts depends on the incorporated amount of nickel and surprisingly correlates with the CoIII/CoIV peak potential. The electrochemical activity of the OER is amazingly improved upon potential cycling. It was observed that potential cycling induces an increase of active sites up to 45% on the most effective electrocatalyst. This unexpected increase in activity is very pronounced and becomes stable after 30 voltammetric cycles. Such a phenomenon is explained by the formation of a layered mixed nickel/cobalt oxyhydroxide active site whose oxidation potential is related to the nickel amount in the catalyst. The formation of this layer is promoted by the surface hydroxylation degree of non-cycled catalysts. In these catalysts, nickel modulates the electronic properties of the active site, which modifies the adsorption energies of key oxygenated intermediates. The synthesis route proposed herein allows an efficient way for obtaining high specific surface areas as well as highly hydroxylated surfaces, the latter being the key factor in the enhancement of the electrocatalytic activity of nickel cobaltites.

Graphical abstract: Three dimensionally ordered mesoporous hydroxylated NixCo3−xO4 spinels for the oxygen evolution reaction: on the hydroxyl-induced surface restructuring effect

Back to tab navigation
Please wait while Download options loads

Supplementary files

Publication details

The article was received on 06 Jan 2017, accepted on 17 Mar 2017 and first published on 17 Mar 2017


Article type: Paper
DOI: 10.1039/C7TA00185A
Citation: J. Mater. Chem. A, 2017,5, 7173-7183
  •   Request permissions

    Three dimensionally ordered mesoporous hydroxylated NixCo3−xO4 spinels for the oxygen evolution reaction: on the hydroxyl-induced surface restructuring effect

    I. Abidat, C. Morais, C. Comminges, C. Canaff, J. Rousseau, N. Guignard, T. W. Napporn, A. Habrioux and K. B. Kokoh, J. Mater. Chem. A, 2017, 5, 7173
    DOI: 10.1039/C7TA00185A

Search articles by author