Metal-Organic Framework-Derived FeS2/CoNiSe2 Heterostructure Nanosheets for Highly-Efficient Oxygen Evolution Reaction

Abstract Developing effective and low-cost catalysts toward oxygen evolution reaction (OER) is pivotal for hydrogen generation by water electrolysis. The preparation of transition metal based catalysts using the unique structure of metal-organic frameworks is considered a feasible approach. Herein, we have designed and synthesized a heterostructure electrocatalyst composed of FeS2 and MOF-derived CoNiSe2. The catalyst exhibits an extraordinary OER activity with a low overpotential of 230 mV to deliver the current density of 10 mA cm-2, a slight Tafel slope of 54 mV dec-1 in 1 M KOH, and robust durability up to 45 h. The result of density functional theory (DFT) calculations reveals that electronic coupling at the heterogeneous interface helps reduce reaction energy barriers and increase electrical conductivity. This work would provide some inspiration for explorations of advanced electrocatalysts with MOF-derived heterostructure.