Rapid Synthesis of Rhodium-Palladium Alloy Nanocatalysts

The chemistry of metastable RhPd alloys is not well understood, and well-characterized nanoparticle (NP) examples remain rare. Well-defined and near-monodisperse RhPd NPs were prepared in a simple one-pot approach by using microwave-assisted or conventional heating in reaction times as short as 30s. The catalytic hydrogenation activity of supported RhPd NP catalysts revealed that short synthesis times resulted in the most-active and most-stable hydrogenation catalysts, whereas longer synthesis times promoted partial Rh-Pd core-shell segregation. Relative to Rh NPs, RhPd NPs resisted deactivation over longer reaction times. Density functional theory (DFT) was employed to estimate the binding energies of H and alkenes on (111) Rh, Pd, and Rh0.5Pd0.5 surfaces. The DFT results concurred with experiment and concluded that the alkene hydrogenation activity trend was of the order Pd