Tunable surface plasmon resonance of Au@Ag2S core-shell nanostructures containing voids

A novel rodlike core-shell nanostructure containing voids between shell and core has been effectively synthesized by the Kirkendall effect. The Au@Ag2S nanoparticles exhibit preferable optical properties due to integrating the absorption behaviors of the Au cores and the Ag2S shells and existence of voids. When Ag is coated on the surface of Au nanorods, the SPR absorption of the Au nanorods shows a blue shift. While Ag is transformed to Ag2S, the SPR absorption of the Au nanorods shifts to high wavenumber. Different shells could adjust and control the SPR absorption of Au nanorods. Moreover, the voids endow the nanostructured materials with other new functions such as catalysis, drug delivery and so on.