The Structure of the Cobalt Oxide/Au Catalyst Interface in Electrochemical Water Splitting

• DOI: 10.1002/ange.201804417
• Publication Date: 2018-07-07T14:45:14Z
• Authors: Jakob Fester; Anton Makoveev; Doris Grumelli; Rico Gutzler; Zhaozong Sun; Jonathan Rodrígue...; Klaus Kern; Jeppe V. Lauritsen
• Keywords: Cobalt oxide; Oxygen evolution

Abstract The catalytic synergy between cobalt oxide and gold leads to strong promotion of the oxygen evolution reaction (OER)—one half‐reaction electrochemical water splitting. However, mechanism behind enhancement effect is still not understood, in part due a missing structural model active interface. Using novel interplay cyclic voltammetry (CV) for electrochemistry integrated with scanning tunneling microscopy (STM) X‐ray photoelectron spectroscopy (XPS) on an atomically defined oxide/Au(111) system, we reveal here that supporting substrate uniquely favors flexible cobalt‐oxyhydroxide/Au interface electrochemically potential window thus suppresses formation less bulk morphologies. findings substantiate why optimum obtained coverages close or below one monolayer, provide first morphological description phase during electrocatalysis.