Patent ID: 8129306
Filing Date: 2012-03-06
Classification: B01J,H01M,Y02E

Abstract:
1. A method of preparing a metal alloy nanoparticle having enhanced catalytic properties, comprising: providing a first noble metal precursor including a first noble metal; providing a first base metal precursor including a first base metal, the first base metal selected based on the first noble metal to effect the electronic configuration of the first noble metal and to preferentially segregate the first noble metal to the surface of the metal alloy nanoparticle; combining a predetermined nominal molar ratio of between about 1:3 and about 3:1 of the first noble metal precursor and the first base metal precursor to form a mixture; and reducing the mixture to form a plurality of metal alloy nanoparticles having a surface shell consisting of the first noble metal and a core of the first noble metal and the base metal and forming a catalytically active surface layer on each of the plurality of metal alloy nanoparticles by further segregating the first noble metal to the surface by heat treating the mixture in a heated hydrogen-containing atmosphere substantially free of oxidizing gas, wherein the mixture is not exposed to a heated oxidizing atmosphere before heat treating the mixture.