Peapod Assemblies of Au and Au/Pt Nanoparticles Encapsulated within Hollow Silica Nanotubes

Abstract

Nanoparticle assemblies within hollow nanoshells represent versatile structures which enable efficient nanosystems with colligative properties of nanoparticles for a variety of applications. In this report, we present a simple and high yielding solution-based synthetic strategy for peapod-shaped Au nanoparticle assembly encapsulated within hollow silica nanotubes (pp multi-Au@SiO2 NTs). One-dimensional, [multiple Au nanodot] core-[silica] shell nanowires (multi-Au@SiO2 NWs) are preferentially synthesized based on reverse microemulsion (water-in-oil) techniques. By thermal treatment of multi-Au@SiO2 NWs in aqueous polyvinylpyrrolidone (PVP) solution, pp multi-Au@SiO2 NTs can be successfully fabricated. Further growth of Pt on the Au nanoparticles in pp multi-Au@SiO2 NTs can lead to the generation of [Au] core-[Pt] shell (Au/Pt) nanoparticle assembly surrounded by silica nanotubes (pp multi-Au/Pt@SiO2 NTs).