In Situ Fabrication of FeCoNi Layered Double Hydroxides as Efficient and Stable Catalysts for Oxygen Evolution Reaction

It is of major significance to develop efficient and durable electrocatalysts for oxygen evolution reactions (OER) to improve the electrochemical performance of various energy storage and conversion devices such as advanced metal-air batteries. Herein, we present a simple room-temperature stirring method for the manufacture of FeCoNi layered double hydroxide (FeCoNi-LDH) nanomaterials by utilizing a homemade metal-organic framework (CoNi-glycerate solid spheres) as a precursor. The FeCoNi-LDHs exhibit a hierarchical yolk-shell structure, with numerous ultra-thin hydroxide nanosheets forming the walls. Because of its unique structure and composition, FeCoNi-LDH-5 only requires an overpotential of 252 mV to drive a current density of 10 mA cm−2and exhibits excellent electrochemical stability. Enhanced activity can be explained by the high electrochemical surface area and low transfer resistance obtained. This work provides a feasible tactic to engineer LDHs as high-efficiency and promising OER electrocatalysts for advanced metal-air batteries.