Nanocrystalline Intermetallics and Alloys

Nanocrystalline intermetallics and alloys are novel materials with high surface areas which are potential low-cost and high-performance catalysts. Here, we report a general approach to the synthesis of a large variety of nanocrystalline intermetallics and alloys with controllable composition, size, and morphology: these include Au-, Pd-, Pt-, Ir-, Ru-, and Rh-based bi- or tri-metallic nanocrystals. We find that only those intermetallics and alloys whose effective electronegativity is larger than a critical value (1.93) can be prepared by co-reduction in our synthetic system. Our methodology provides a simple and convenient route to a variety of intermetallic and alloyed nanomaterials which are promising candidates for catalysts for reactions such as methanol oxidation, hydroformylation, the Suzuki reaction, cyclohexene hydroconversion, and the selective hydrogenation of acetylene.