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.