Abstract
Ruthenium-Carbon (Ru-C) nano-composite films were prepared by plasma-enhanced chemical vapor deposition (PECVD) and the effects of deposition conditions on the microstructure and electrical properies were investigated. The films consisted of agglomerated grains of 10 to 20 nm in diameter, in which Ru particles of 2.5 to 3.5 nm in diameter were dispersed in a C matrix. The C content of the films was about 90 vol%. The electrical properties of Ru-C nano-composite films as a catalytic electrode for an yttria-stabilized zirconia (YSZ) solid electrolyte were evaluated by AC impedance spectroscopy. The interfacial electrical conductivity at the Ru-C/YSZ interface was 0.2×10−3 Sm−1 at 500 K and increased with increasing temperature. The activation energy of the interfacial electrical conductivity was about 70 kJ/mol, implying an oxygen diffusion limited process at the interface.