Strong Catalyst-Support Interactions in Electrochemical Oxygen Evolution on Ni-Fe Layered Double Hydroxide

Strong catalyst-support interaction plays a key role in heterogeneous catalysis, as has been well-documented in high-temperature gas-phase chemistry, such as the water gas shift reaction. Insight into how catalyst-support interactions can be exploited to optimize the catalytic activity in aqueous electrochemistry, however, is still lacking. In this work, we show the rationally designed electrocatalyst/support interface can greatly impact the overall electrocatalytic activity of Ni-Fe layered double hydroxide (NiFeLDH) in water oxidation. In particular, the use of Co as a non-noble metal support greatly improves the activity of NiFeLDH 10-fold compared to the traditional electrocatalytic supports such as fluorine-/indium-doped tin oxide (FTO/ITO) and glassy carbon. We attribute the activity enhancement of NiFeLDH/Co to the in situ formation of a porous NiFeCoOxHy layer via Co incorporation, which dramatically promotes the redox chemistry of metal centers on the outer surface and enhances the electrical conductivity of the catalyst over 2 orders of magnitude. This new discovery highlights the importance of a rationally designed electrocatalyst/support interface and offers a new paradigm for designing and developing highly active electrocatalytic systems via marrying catalyst and support and creating synergy.