Synergistic metal-oxide interaction for efficient self-reconstruction of cobalt oxide as highly active water oxidation electrocatalyst

Developing catalysts with outstanding performance for oxygen evolution reaction (OER) is crucial to advance energy conversion technologies. In these regards, catalysts based on 3d transition metals have recently attracted much attention, yet further development is required. Here, we present a new type of heterostructure catalyst in which CoO nanowire arrays are hybridized with tungsten nanoparticles (W-CoO), and are self-supported on conductive carbon cloth (CC). Electronic coupling effects at the W-CoO heterointerface promote electron transfer and OER kinetics to expedite the formation of oxyhydroxide species, which are the active sites for OER processes. A variety of in situ and ex situ characterization methods are employed to reveal deep insights into surface transformations and investigate the relationship between the conversion to oxyhydroxide moieties and OER performance. This report presents new understanding of the rational design and synthesis of catalysts that exhibit outstanding performance as electrochemical water splitting electrode for OER.