Controlled synthesis of core-shell Fe@Au faceted nanoparticles

Core-shell Fe@Au crystalline NPs, particularly suitable for biomedical applications, have been successfully synthesized by sequential deposition from two elemental targets in a ultrahigh vacuum sputtering device. The size of the NPs, in the 8–15 nm range, is controlled by the deposited Fe volume. The obtained NPs adopt an original polyhedral core-shell morphology in which a Fe nanocube core acts as a nanosubstrate for the epitaxial growth of gold islands with a truncated pyramid shape. The morphological, structural and chemical properties of the NCs are studied through advanced TEM based techniques (HREM, STEM-HAADF, EDX) down to the atomic scale.