Characterization of the Mixed Proton-Electron Conductivity of Nanostructured Hydrous Ruthenium Oxides by Electrochemical Impedance Spectroscopy

Abstract

Hydrous nanoparticulate and layered ruthenium oxides are candidates as high energy and high power electrochemical supercapacitor electrode materials. The mixed proton-electron conductivity of these hydrous materials has been postulated to be one of the reasons for the high energy capability. In this study, we explored the mixed conductivity of hydrous ruthenium oxides using electrochemical impedance spectroscopy and its relation with the supercapacitive behavior. The high capacitance of nanostructured hydrous ruthenium oxides was found to be due to the utilization of hydrated micropores and interlayer with the sacrifice of power capability. On the other hand, the variation in the electronic conductivity due to the change in water content or structure was insignificant.