Intrinsic quantum conductances and capacitances of nanowires and nanocables

Here we calculate the intrinsic quantum capacitance of RuO2 nanowires and RuO2/SiO2 nanocables (filled interiors, or nanotubes, which are empty), based upon available ab initio density of states values, and their conductances allowing determination of transmission coefficients. Comparisons are made to the intrinsic quantum capacitance of carbon nanotubes, and to RuO2 and RuO2/SiO2 Schottky and p-n junction capacitances. We find that the intrinsic quantum capacitance of RuO2 based nanostructures dominates over its junction capacitances by an order of magnitude or more, having important implications for energy and charge storage.