XRD and electrochemical measurements of RuO2 powder treated by using a mechanical grinding method

Atomization, crystallinity, and electrochemical characteristics of powdery RuO2 treated by mechanical grinding (MG) were examined. XRD analysis, N-2 adsorption/desorption measurements, and TEM observations showed that MG generated isotropic and rapid atomization of RuO2 particles in the initial stage of treatment (up to 190 h). Further MG resulted in gentle atomization with anisotropy in a and c axial directions. Electrochemical measurements showed that the specific capacitance of treated RuO2 increased with increasing MG time. By the MG 400 h treatment, the specific capacitance was 132 F/g, which was about 80-tinies greater than that of the untreated sample. This increment was attributed to the increase in the specific surface area of RuO2 powder owing to the isotropic atomization caused by MG treatment. (C) 2003 Elsevier B.V. All rights reserved.