Synthesis and electrochemical capacitor performance of mesostructured nickel oxide/carbon composites by a co-casting method

We present a new co-casting method to synthesize novel mesostructured NiO/C composites with NiO nanoparticles studded in the wall of ordered mesoporous carbon materials. Ni2+ ions were captured by the framework of partially polymerized sucrose in the channel of mesoporous silica; during the carbonization process, Ni(NO)2.6H2O was decomposed and NiO nanoparticles was formed and confined in the carbon framework. Thermogravimetric analysis (TG), X-ray diffraction (XRD), nitrogen sorption, transmission electron microscopy (TEM), and cyclic voltammetry (CV) were employed to characterize the composite materials. Increasing the NiO content does not decrease the specific surface area dramatically and it remains ∼1000 m2/g when the NiO content reaches 15.2 wt%. Such composites have a large specific capacitance over 243 F/g and the specific capacitance for NiO reaches 456 F/g.