Hydrothermal Synthesis of NiCo2O4/Activated Carbon Composites for Supercapacitor with Enhanced Cycle Performance

Owing to the advantages of the good conductive AC and high capacitive NiCo2O4, We prepared a series of NiCo2O4/AC composites by a hydrothermal method. The morphology of NiCo2O4/AC composites indicate the NiCo2O4 nanoplates with diameters of about 0.5 similar to 1 mm and thickness of about 20 nm are coated on AC. The electrochemical investigation demonstrate that the specific capacitances of NCO-AC-3 (containing 47% NiCo2O4) are 273.5 Fg(-1) and the capacity retention still retains at 96% (262.6 Fg(-1)) after 3000 cycles at current density of 1 Ag-1, especially, the cycling stability maintain more stable at high current density. Therefore, the low-cost NiCo2O4/AC composites can serve as a promising electrode material for high performance supercapacitors due to the synergistic effect between the electric double-layer capacitance of porous AC and the pseudocapacitance of NiCo2O4 nanoplates.