title: Composition-controlled synthesis of bimetallic gold-silver nanoparticles.
abstract: This paper reports findings of an investigation of the synthesis of monolayer-capped binary gold-silver (AuAg) bimetallic nanoparticles that is aimed at understanding the control factors governing the formation of the bimetallic compositions. The synthesis of alkanethiolate-capped AuAg nanoparticles was carried out using two related synthetic protocols using aqueous sodium borohydride as a reducing agent. One involves a two-phase reduction of AuCl(4)(-), which is dissolved in organic solution, and Ag(+), which is dissolved in aqueous solution. The other protocol involves a two-phase reduction of AuCl(4)(-) and AgBr(2)(-), both of which are dissolved in the same organic solution. AuAg nanoparticles of 2-3 nm core sizes with different compositions in the range of 0-100% Au have been synthesized. The two synthetic routes were compared in terms of bimetallic composition and size properties. Our new findings have allowed us to establish the correlation between synthetic feeding of metals and metal compositions in the bimetallic nanoparticles, which have important implications to the exploration of gold-based bimetallic nanoparticles for constructing sensing and catalytic nanomaterials.
authors.affiliation: Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902, USA.
authors.forename: Nancy N
authors.initials: NN
authors.lastname: Kariuki
authors.forename: Jin
authors.initials: J
authors.lastname: Luo
authors.forename: Mathew M
authors.initials: MM
authors.lastname: Maye
authors.forename: Syed A
authors.initials: SA
authors.lastname: Hassan
authors.forename: Tanya
authors.initials: T
authors.lastname: Menard
authors.forename: H Richard
authors.initials: HR
authors.lastname: Naslund
authors.forename: Yuehe
authors.initials: Y
authors.lastname: Lin
authors.forename: Chongmin
authors.initials: C
authors.lastname: Wang
authors.forename: Mark H
authors.initials: MH
authors.lastname: Engelhard
authors.forename: Chuan-Jian
authors.initials: CJ
authors.lastname: Zhong
mesh_terms: D006046:Gold / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D012834:Silver; D006046:Gold