title: Core/shell Au/CuPt nanoparticles and their dual electrocatalysis for both reduction and oxidation reactions.
abstract: We report a facile synthesis of monodisperse core/shell 5/1.5 nm Au/CuPt nanoparticles by coreduction of platinum acetylacetonate and copper acetylacetonate in the presence of 5 nm Au nanoparticles. The CuPt alloy effect and core/shell interactions make these Au/CuPt nanoparticles a promising catalyst for both oxygen reduction reaction and methanol oxidation reaction in 0.1 M HClO4 solution. Their specific (mass) reduction and oxidation activities reach 2.72 mA/cm(2) (1500 mA/mg Pt) at 0.9 V and 0.755 mA/cm(2) (441 mA/mg Pt) at 0.8 V (vs reversible hydrogen electrode), respectively. Our studies show that the existence of the Au nanoparticle core not only minimizes the Pt usage but also improves the stability of the Au/CuPt catalyst for fuel cell reactions. The results suggest that the core/shell design is indeed effective for optimizing nanoparticle catalysis. The same concept may be extended to other multimetallic nanoparticle systems, making it possible to tune nanoparticle catalysis for many different chemical reactions.
authors.affiliation: Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States.
authors.forename: Xiaolian
authors.initials: X
authors.lastname: Sun
authors.forename: Dongguo
authors.initials: D
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Ding
authors.forename: Wenlei
authors.initials: W
authors.lastname: Zhu
authors.forename: Shaojun
authors.initials: S
authors.lastname: Guo
authors.forename: Zhong Lin
authors.initials: ZL
authors.lastname: Wang
authors.forename: Shouheng
authors.initials: S
authors.lastname: Sun