Mesoporous hexagonal nanorods of NiCo2O4 nanoparticles via hydrothermal route for supercapacitor application

Abstract

Binary metal oxide with a mesoporous microstructure has been considered a potential candidate electrode material for supercapacitor. The mesoporous microstructure of binary metal oxide improves electric conductivity. A mesoporous hexagonal microstructure of NiCo2O4 nanorods has been fabricated by a chemical hydrothermal method. Mesoporous hexagonal nanorods composed of small nanoparticles with an average thickness of 412 nm are prepared with a 14-hour hydrothermal reaction time. As synthesized, mesoporous hexagonal nanorods of NiCo2O4 as an electrode material show the highest specific capacitance of 1061 F/g and 184 mF/cm2 areal capacitance. The specific energy and specific power density of the NiCo2O4 electrode are 39 WhKg−1 and 683 Wkg−1. The equivalent charge resistance (Rs) and charge transfer resistance (Rct) of the NiCo2O4 electrode are 0.70 Ω and 43 Ω respectively. The NiCo2O4 electrode had an initial capacitance retention value of 81% after 3000 cycles.