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Monolayer films of highly catalytically active Pd@CeO2 core-shell nanocomposites were grafted onto a planar YSZ(100) (yttria-stabilized zirconia, YSZ) single crystal support that was functionalized with a CVD-deposited layer of triethoxy(octyl)silane (TEOOS). The resulting monolayer films were found to exhibit exceptionally high thermal stability compared to bare Pd nanoparticles with the Pd@CeO2 nanostructures remaining intact and highly dispersed upon calcining in air at temperatures in excess of 1000 K. The CeO2 shells were also shown to be more easily reduced than bulk CeO2, which may partially explain their unique activity as oxidation catalysts. The use of both TEOOS and tetradecylphosphonic acid (TDPA) as coupling agents for dispersing Pd@CeO2 core-shell nanocomposites onto a high surface area γ-Al2O3 support is also demonstrated.

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Submonolayer films of highly catalytically active Pd@CeO2 nanocomposites, consisting of a Pd nanoparticle core coated with a porous CeO2 shell, were deposited onto porous solid oxide fuel cell (SOFC) anodes that were functionalized with triethoxy(octyl)silane (TEOOS). SEM results show that in contrast to bare Pd particles, Pd@CeO2 particles grafted onto the surface of the ceramic anode remained highly dispersed, even after calcination in air at 1373 K. SOFC with anodes that were modified with very low loadings (0.01 wt %) of the Pd@CeO2 nanocomposites were shown to exhibit good electrochemical performance when operating with either H2 or CH4 fuels at 973 K. This performance was also maintained after annealing the anode in air at 1173 K. These results demonstrate a strategy for using very low loadings of highly active metal catalysts to enhance the activity of ceramic anodes while maintaining long-term stability.

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