Abstract: A system and method to tailor the optical properties of nanomaterials using a core-alloy-shell nano-ultrastructure. Atomic diffusion is used at the nanoscale in order to process as-synthesized nanomaterials into core-alloy-shell architectures. The alloy formation is controlled by the deposition of the alloy solute atoms, and then by alloy interdiffusion of the solute into the core nanoparticle. By controlling temperature, it is possible to control how far the solute diffuses into the core, which in turn allows the tailoring of the optical response of the particle itself. The alloy formation and subsequent interdiffusion allows tailoring of the nanoparticle composition and ultrastructure, resulting in a dramatic tunability of the metal nanostructures surface plasmon response.

Abstract: A method of preparing carbon-loaded, gold-based nanoparticle catalysts useful as anode catalysts for the electrocatalytic methanol oxidation reaction (MOR) as well as the oxygen reduction reaction (ORR). AumPtnM100-m-n catalysts may be prepared by either a two-phase protocol or by a thermal decomposition/reduction protocol. The prepared nanoparticles having different bimetallic ratios are assembled on carbon black support materials and activated by thermal treatment. This approach provides good control of nanoparticle size, composition and/or surface properties. Electrocatalytic MOR activities of the prepared and activated AuPt nanoparticle provided in accordance with the methods of the invention are present in both acidic and alkaline electrolytes.

Abstract: A method of synthesizing highly monodispersed Au nanoparticles having diameters in the range of 30-90 nm. Seed nanoparticles in a controlled concentration are combined with a precursor, also in a controlled concentration, a reducing and capping agent (e.g., sodium acrylate) in aqueous solution. Under controlled conditions of pH, temperature, and time, highly monodispersed nanoparticles having diameters in the range of 30-100 nm are produced. A relative size standard deviation of the size distribution of the resulting nanoparticles is as low as 2%.