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

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 MA-Ag-MB 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.