Synthesis of CuPt nanorod catalysts with tunable lengths.

Solution chemistry methods have been used to synthesize bimetallic CuPt alloy nanoparticle catalysts with controllable sizes and shapes. By variation of the relative ratios of the oleylamine and oleic acid stabilizers, solvent, and reduction rate, the nanoparticles could be tuned from approximately 2 nm spherical particles to nanorods with diameters of approximately 2.5 nm and aspect ratios tunable from 5:1 to 25:1. These mixed-metal nanoparticles show excellent catalytic properties for CO oxidation, with light-off temperatures that are nearly 200 K below those of conventional supported Pt catalysts.