Morphology-controlled fabrication of hierarchical mesoporous NiCo2O4 micro-/nanostructures and their intriguing application in electrochemical capacitors

Abstract

Hierarchical NiCo₂O₄ micro-/nanostructures constructed with mesoporous nanowire or nanosheet building blocks have been controllably fabricated via a facile two-step strategy involving a solvothermal route and a post-annealing treatment. The tunable morphologies can be easily achieved through simply altering the properties of the reaction solvents. The well-defined hierarchical NiCo₂O₄ micro-/nanostructures apparently possess intriguing structural advantages, such as fast electron and ion transport, high electroactive surface area, and excellent mechanical stability. As a result, the two hierarchical NiCo₂O₄ micro-/nanostructures demonstrate large specific capacitance coupled with excellent cycling stability when evaluated as striking electrode materials for high-performance electrochemical capacitors.