Designed Formation of Double-Shelled Ni-Fe Layered-Double-Hydroxide Nanocages for Efficient Oxygen Evolution Reaction.

Delicate design of nanostructures for oxygen-evolution electrocatalysts is an important strategy for accelerating the reaction kinetics of water splitting. In this work, Ni-Fe layered-double-hydroxide (LDH) nanocages with tunable shells are synthesized via a facile one-pot self-templating method. The number of shells can be precisely controlled by regulating the template etching at the interface. Benefiting from the double-shelled structure with large electroactive surface area and optimized chemical composition, the hierarchical Ni-Fe LDH nanocages exhibit appealing electrocatalytic activity for the oxygen evolution reaction in alkaline electrolyte. Particularly, double-shelled Ni-Fe LDH nanocages can achieve a current density of 20 mA cm-2 at a low overpotential of 246 mV with excellent stability.