Bimetallic nanocobs: Decorating silver nanowires with gold nanoparticles

Abstract

A study was conducted to demonstrate a novel design of hybrid and bimetallic silver-gold core-double-shell nanowires with greatly enhanced surface-enhanced Raman scattering (SERS) ability. The study demonstrated the novel design, in which gold nanoparticles decorate the surface of silver nanowires, utilizing a three-arm star polymer with functional terminal groups as a linker. It was found that the gold nanoparticles form an effective and hybrid shell of 13 nm thickness with 4 nm gold nanoparticles embedded within the polymer shell around a 65 nm silver core. It was also demonstrated that such hybrid silver-gold nanowires possess significant SERS activity, exceeding the Raman scattering observed from isolated silver nanowires. The SERS is also observed to be much higher than that at the gap between two neighboring silver nanowires.