hide
Free keywords:
activation; Ag2O nanoclusters; iron incorporation; ordered mesoporous Co3O4; oxygen evolution reaction
Abstract:
Herein, we show that performance of mesostructured cobalt oxide electrocatalyst for oxygen evolution reaction (OER) can be significantly enhanced with coupling of silver species. Various analysis techniques including pair distribution function and Rietveld, X-ray absorption spectroscopy at synchrotron as well as advanced electron microscopy revealed that silver exists as metallic Ag particles and well-dispersed Ag2O nanoclusters within mesostructure. The benefits of this synergy are twofold for OER: highly conductive metallic Ag improves the charge transfer ability of the electrocatalyst while ultra-small Ag2O clusters provide the centers that can uptake Fe impurities from KOH electrolyte and boost the catalytic efficiency of Co-Ag oxides. The current density of mesostructured Co3O4 at 1.7 VRHE is increased from 102 to 211 mA cm-2 with incorporation of silver spices. This work presents the dual role of silver moieties and demonstrates a simple method to increase the OER activity of Co3O4.
