Facile Hydrothermal Synthesis and Electrochemical Performance of NiCo2O4 Nanoneedles

Abstract

NiCo2O4 nanoneedles on the surface of Ni foam were grown by a simple one step hydrothermal method, which is used as the working electrode for asymmetric supercapacitors. Its area specific capacitance is 981.64 C cm–2 at 1 mA cm–2, and the cycling stability can reach 100% after 10000 cycles at 4 mA cm–2. The spatial structure of the nanoneedle has important influence on the cyclic stability of NiCo2O4 electrode. The hybrid supercapacitors are prepared on the basis of the prepared NiCo2O4 nanoneedle electrodes. After 8000 cycles, its cycle life is stable and the capacitance retention rate reaches 100%.