Catalysts for Low-Temperature CO Oxidation Based on Platinum, CeO2, and Carbon Nanotubes

Nanocomposite catalysts based on highly dispersed platinum and ceria particles supported on carbon nanotubes were studied. The composites were prepared using the complex (\Me4N)(2)[Pt-2(mu-OH)(2)(NO3)(8)] as the platinum precursor. This approach ensured stabilization of platinum nanoparticles, clusters, and single atoms/ions on the surface of both ceria and the carbon nanomaterial. Study of the catalytic activity of the samples showed that highly dispersed metallic platinum species stabilized directly on the surface of carbon nanotubes can efficiently oxidize CO present in low concentrations in a reaction mixture at room temperature, in particular, in the presence of water vapor. However, low-temperature CO oxidation at higher CO concentrations requires formation of new active sites through interaction of platinum ions with ceria particles.