3D Self-Supported FeOOH@C Hybrid Nanosheet Arrays as Electrocatalyst for Oxygen Evolution

FeOOH has attracted great research attention in the electrocatalytic oxygen evolution reaction (OER) because of its low cost, natural abundance, environmental friendliness, and high intrinsic activity. However, the practical utilization of FeOOH is seriously restricted by its inherent poor conductivity. Herein, the hybridization of FeOOH with N-doped porous carbon (NPC) nanosheets derived from metal–organic framework (MOF) supported on Ni foam (NF) has been proved to be an effective approach to improve the electrocatalytic OER activity of FeOOH. The MOF-derived porous NPC nanosheets have a unique interpenetrating three-dimensional (3D) network architecture, which can not only serve as a highly conductive layer to promote electron transfer but also improve the utilization rate of FeOOH and facilitate mass transport. Owing to the advantages in structure and composition, the as-obtained FeOOH@C/NF exhibits significantly enhanced electrocatalytic performance toward OER in alkaline media, with a current density of 10 mA cm–2 at an overpotential of 182 mV, a small Tafel slope of 27.9 mV dec–1, and excellent durability.