Preparation of AucoreAgshell nanorods and characterization of their surface plasmon resonances

The surface of gold nanorods is coated with thickness-controlled silver by reducing AgCl43- exclusively on the metallic surface to form AucoreAgshell nanorods and then restored by selectively removing the silver coating. AucoreAgshell nanorods show much sharper, stronger, and shorter-wavelengthed surface plasmon absorption than gold nanorods. However, the absorption wavelength is much longer than the one calculated for pure Ag nanorods. This means that the core-shell structure of AucoreAgshell nanorods must be explicitly taken into account in these calculations.