A core–shell templated approach to the nanocomposites of silver sulfide and noble metal nanoparticles with hollow/cage-bell structures

Abstract

The integration of semiconductor and noble metal nanoparticles with controlled structures into a nanosystem can effectively couple various effects specific to the different domains of the nanocomposite for greater application versatility. Herein, we demonstrate the general synthesis of nanocomposites of Ag₂S and noble metal nanoparticles with a hollow or cage-bell structure. The synthesis is based on the inside-out diffusion of Ag in core–shell nanoparticles. It begins with the preparation of core–shell Ag–M or core–shell–shell M_A–Ag–M_B nanoparticles in an organic solvent. The Ag is then removed from the core or from the internal shell and converted into Ag₂S by elemental sulfur or sodium sulfide. The Ag₂S forms the semiconductor domain in the nanocomposite and shares solid-state interfaces with the resultant hollow or cage-bell structured metal nanoparticle. The structural transformation from core–shell to heterogeneous nanocomposites may provide new opportunities to design and fabricate hybrid nanostructures with interesting physicochemical properties.