Synthesis and characterization of Co(OH)2/TiO2 nanotube composites as supercapacitor materials

A novel composite of Co(OH)(2) and TiO2 nanotubes was synthesized by a chemical precipitation method. Co(OH)(2)/TiO2 nanotube composites and its microstructure were characterized by transmission electron microscopy (TEM), X-ray diffraction pattern (XRD). The electrochemical capacitance performance of this composite was investigated by cyclic voltammetry and charge-discharge tests with a three-electrode system in 6 M KOH solution. We synthesized different weight ratios of Co(OH)(2)/TiO2 nanotubes, a maximum specific capacitance of 229 F/g was obtained for the composite. Based on these tests, we propose that TiO2 nanotubes provide the three-dimensional nanotube network structure for the composite and make the Co(OH)(2) dispersed. For these reasons, the TiO2 nanotubes used as a framework for Co(OH)(2) improve the utilization of Co(OH)(2) greatly.