A novel facile and template-free method to prepare a nanoball-like NiO x material has been developed. The preparation involves the synthesis of an α-Ni(OH) 2 precursor by microwave heating and calcination of the precursor. The NiO x material possesses a nanoball-like structure with a large surface area. The pseudo-capacitive properties of the NiO x material were evaluated by cyclic voltammetry and electro-chemical impedance spectroscopy in 6 M KOH solution. The specific capacitances were 951, 796, 713 and 650 F g -1, corresponding to the scan rates of 2.0, 5.0, 10 and 20 mV s -1, respectively. The NiO x material also showed excellent cycling stability and maintained 92% of its maximum specific capacitance after 1000 cycles. The hybrid supercapacitor based on this NiO x material exhibited moderate energy density and power density.
Scopus Subject Areas
- Materials Chemistry