Interface Synergistic Effect of NiFe-LDH @ 3D GA Composites towards Efficient Electrocatalytic Water Oxidation

Currently, NiFe-LDH exhibits excellent oxygen evolution reaction (OER) due to the interaction of the two metal elements on the LDH platform. However, such interaction is still insufficient to compensate for its poor electrical conductivity, limited active sites and sluggish dynamics. Herein, a feasible two-step hydrothermal strategy is proposed by coupling low-conductivity NiFe-LDH with 3D porous graphene aerogel (GA). Consequently, the optimized NiFe-LDH/GA (1:1) possess a 257 mV (10 mA cm-2) overpotential and could continuously operate for 56 h in OER. Our investigation validates that the NiFe-LDH/GA has a three-dimensional mesoporous structure, synergistic interaction between LDH and GA, and interfacial reconstruction of NiOOH. Such interface synergistic coupling effect promotes fast mass transfer and facilitates OER kinetics, and this work offers new sights into designing efficient and stable GA-based electrocatalysts.