RuO₂ nanoparticle-modified (Ce,Mn,Fe)O₂/(La,Sr) (Fe,Mn)O₃ composite oxide as an active anode for direct hydrocarbon type solid oxide fuel cells

Composite oxide anodes have recently attracted great attention as alternative materials for solid oxide fuel cell anodes because of their potential to overcome the serious performance deterioration associated with the traditional Ni-based cermet. In particular, oxide anodes show a greater tolerance to coke and reoxidation than existing Ni-based cermets. In this study, the anodic performance of a (Ce,Mn,Fe)O₂/(La,Sr) (Fe,Mn)O₃ composite oxide modified with additional amounts of catalytically active RuO₂ nanoparticles was investigated. Heat treatment resulted in highly dispersed RuO₂ particles (ca. 10 nm). Anodes containing 10 wt% added RuO₂ exhibited fairly high maximum power densities of 0.3 and 1.5 W cm^-2 in H₂ and C₃H₈, respectively, at 800 °C. The cells showed stable power density and negligible carbon formation even after 50 h of operation at 1 A cm^-2. The increased power density was assigned to decreased anodic overpotential and internal resistance losses because RuO₂ nanoparticles contribute to the increase in electrical conductivity.