Temperature-induced Hollow Hierarchical NiCo2O4 Microspheres for High Performance Pseudocapacitors

Abstract

Spinel nickel cobaltite (NiCo2O4) has been proved to be one of the most promising electrode materials for high performance supercapacitors due to its high theoretic specific capacitance, excellent electronic conductivity and good environmental benignity. In this work, the unique NiCo2O4 structure was fabricated hydrothermally via the induction of the reaction temperature and investigated electrochemically as supercapacitor electrode material. The resultant NiCo2O4 electrode with hollow hierarchical microspherical structure as supercapacitor displays excellent capacitive characteristic with higher specific capacitance, better cycling stability and rate capability compared to those with various morphologies, revealing the morphology dependence of the capacitive properties of NiCo2O4 electrode owing to the discrepant electronic conductivity and ion diffusion behavior. Thus, the temperatureinduced changes in morphology are potential in the large-scale fabrication of NiCo2O4 electrode materials as supercapacitors.