Supercapacitor electrode with a homogeneously Co3O4-coated multiwalled carbon nanotube for a high capacitance.

Cobalt oxide (Co3O4) was homogeneously coated on multiwalled carbon nanotube through a simple chemical deposition method and employed in supercapacitor electrodes. SEM image indicated the uniform distribution of Co3O4 nanoparticles on the surface of the multiwalled carbon nanotube. A maximum specific capacitance of 273 Fg(-1) was obtained at the charge-discharge current density of 0.5 Ag(-1). After 500 cycles of continuous charge-discharge process, about 88% of the initial capacity could be retained.