To meet the increasing demand for high power energy storage systems, supercapacitors have been intensively developed in recent years. Supercapacitors have attracted great interest among researchers because they have higher power density than batteries and higher energy density than conventional dielectric capacitors. Supercapacitors can be divided into two types: electrochemical double layer capacitance and pseudocapacitance (i.e. transition metal oxides). Transition metal hydroxides exhibit high pseudocapacitance, and nanostructured carbon materials have high electrochemical double layer capacitance as well as high electronic conductivity. Therefore, transition metal hydroxide/nanostructured carbon hybrid material can enhance the specific capacitance and electronic conductivity thus increase both energy density and power density.
In this research, we used a facile hydrothermal method to synthesize a novel ternary metal hydroxide/nanostructured carbon hybrid material as electrode for supercapacitors. This hybrid material exhibited high specific capacitance (> 1000 F g-1) which was mainly contributed from ternary metal hydroxide, while showed good capacitance retention which was benefited from nanostructured carbon. The crystallinity and microstructure of this ternary metal hydroxide/nanostructured carbon hybrid material were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemical properties were characterized by cyclic voltammetry and galvanostatic charge/discharge cycle measurements.