Solvothermal synthesis of mesoporous NiCo2O4 spinel oxide nanostructure for high-performance electrochemical capacitor electrode

NiCo2O4 nanostructure was successfully synthesized via a d-glucose-assisted solvothermal process. Spinel-type cubic phase and mesoporous microstructure of the sample for different calcination temperatures were confirmed by X-ray diffraction and transmission electron microscopy. Typical pseudocapacitance feature of the NiCo2O4 treated at different temperatures was then evaluated in aqueous 6 M KOH electrolyte solution. Electrochemical measurements showed that the spinel nickel cobaltite nanostructure heated at 300 A degrees C exhibits maximum specific capacitances of 524 F g(-1) at 0.5 A g(-1) and 419 F g(-1) at 10 A g(-1) with excellent cycle stability and only similar to 9 % of capacitance loss after 2,500 cycles. This demonstrates the potential application of the material for supercapacitors. The attractive pseudocapacitive performance of NiCo2O4 is mainly attributed to the redox contribution of the Ni and Co metal species, high surface area, and their desired mesoporous nanostructure.