Mn-Doped NiFe Layered Double Hydroxide Nanosheets Decorated by Co(OH)2 Nanosheets: A 3-Dimensional Core–Shell Catalyst for Efficient Oxygen Evolution Reaction

Abstract Exploiting highly active and robust non-noble-metal electrocatalysts for oxygen evolution reaction (OER) occupies an important position in alleviating energy crisis and maintaining social sustainability. Herein, we have grown Co(OH) 2 nanoarrays in situ on Mn-doped NiFe LDH nanosheets to construct Mn-doped NiFe LDH@Co(OH) 2 /NF (MNF@Co(OH) 2 /NF) with core–shell structure. Due to the optimized electronic structure by manganese ion doping and the high density exposure of active sites induced by cobalt hydroxide coating, the MNF@Co(OH) 2 /NF exhibits excellent OER performances, which possesses ultralow overpotentials of 193 and 244 mV at the current densities of 10 and 100 mA cm −2 separately, and possesses a small Tafel slope of 48.4 mV dec −1 . This work offers a new perspective for the rational construction of efficient OER electrocatalysts with multi-dimensional nanostructures to improve the catalytic activity. Graphic Abstract