Binding Energy Optimization Strategy Inducing Enhanced Catalytic Performance on MIL-100(FeNi) To Catalyze Water Oxidation Directly

Abstract

Metal–organic frameworks (MOFs) are recently reported with promising perspective to catalyze oxygen evolution reaction (OER) directly, while their wide applications are generally limited by its unsatisfied catalytic activity and stability during the reaction process. Herein, we synthesized Fe and Ni based bimetallic MOFs on 3D nickel foam (NF), i.e. MIL-100(FeNi)/NF, via a solvothermal process to serve directly as highly efficient OER electrocatalysts. The obtained MIL-100(FeNi)/NF requires a low overpotential of 243 mV to deliver the current density of 100 mA cm–2 under a small Tafel slope value of 30.4 mV dec–1. Density functional theory (DFT) calculations reveal that the metal–metal coupling effect plays a crucial role in determining the pronounced OER performance of the formed MIL-100(FeNi). Hopefully, the synthetic strategy and proposed model of bimetallic electrocatalysts (MIL-100(FeNi)) could simulate the exploration of more novel bimetallic or multimetallic MOFs toward energy storage/conversion application.