Metal–Organic Framework-Derived Bimetallic NiFe Selenide Electrocatalysts with Multiple Phases for Efficient Oxygen Evolution Reaction

The development of efficient and stable transition bimetallic chalcogenides to replace precious metal electrocatalysts for alkaline oxygen evolution reaction (OER) remains an ongoing challenge. Here, a bimetallic NiFe selenide catalyst synthesized by facile selenization of NiFe Prussian blue analogue (PBA) metal–organic framework (MOF) nanoparticle precursors is reported for efficient OER in alkaline solutions. Through two-step electrodeposition and post-thermal pyrolytic selenization, mixed NiFe selenide supported by carbon fiber paper (NiFe-Se/CFP) can be facilely prepared. A low overpotential of 281 mV is required by the NiFe-Se/CFP electrode to deliver a current density of 10 mA cm–2; additionally, an accelerated electron-transfer kinetics is obtained with a Tafel slope of 40.93 mV dec–1 in 1 M KOH solution. The electrocatalytic current density shows negligible loss during 20 h continuous electrolysis, suggesting good stability during long-term alkaline OER. Using the MOF precursor and establishing an in situ phase transformation endow mixed NiFe selenide with highly active surface catalytic sites and high electrical conductivity for efficient water oxidation.