Template Synthesis of Tubular Ruthenium Oxides for Supercapacitor Applications

Nanotubular ruthenium oxides were prepared by using manganite nanorods as a morphology sacrificial template. Experimental results showed that the template dissolved away completely during the formation of the ruthenium oxide nanotubes. A mechanism was proposed to interpret the formation of the ruthenium oxide nanotubes. The electrochemical capacitive properties of the ruthenium oxide nanotubes were investigated using cyclic voltammetry and charge/discharge techniques with H2SO4 and Na2SO4 solutions as the electrolytes, respectively. The specific capacitance of the nanotubular ruthenium oxide electrode was measured to be as high as 860 F/g at a current density of 500 mA/g in the H2SO4 electrolyte, which was higher than that obtained in the Na2SO4 electrolyte. In addition, the ruthenium oxide nanotubes were observed to exhibit a good capacitive retention at high current loads.