Boosting electrocatalytic oxygen evolution by synergistically coupling layered double hydroxide with MXene

Oxygen evolution reaction (OER) is cornerstone reaction of many renewable energy technologies. Cost-effective yet efficient electrocatalysts are critical to overcome the high overpotential and sluggish kinetics of this process. The development of efficient non-precious metal catalysts is one of the crucial but very challenging steps to this end. Herein, we report a new type of non-precious metal electrocatalyst for OER by synergistically coupling layered double hydroxides (LDH) with two-dimensional (2D) MXene with high conductivity and active surface. Hierarchical FeNi-LDH/Ti3C2-MXene nanohybrids with excellent structural stability, electrical properties and interfacial junction are fabricated by ionic hetero-assembly of interconnected porous network of FeNi-LDH nanoplates on Ti3C2 MXene nanosheets. Strong interfacial interaction and electronic coupling with prominent charge-transfer between the FeNi-LDH and Ti3C2 MXene is identified, which not only improves the structural stability and electrical conductivity of the nanohybrids, but also greatly accelerates the redox process of FeNi-LDH for OER. As a result, the FeNi-LDH/Ti3C2-MXene catalyst could exhibit superior activity, reaction kinetics and durability to RuO2 and its graphene-based counterpart for OER in alkaline medium. This work may pave the way on the development of a new branch of advanced electrocatalysts for renewable energy applications.