Controlled Alloying of Au@Ag Core–Shell Nanorods Induced by Femtosecond Laser Irradiation

Bimetallic nanoparticles display unique physical and chemical properties, including improved stability, enhanced optical or higher catalytic activity. Here, a synthetic methodology is described to obtain bimetallic heterostructures alloyed plasmonic nanocrystals through the irradiation of colloidal Au@Ag core–shell nanorods (Au@Ag NRs) with femtosecond laser pulses. Depending on energy deposited NRs, different morphologies degrees alloying are obtained, such as hot-dog-like rice-like (partially alloyed) well fully nanospheres. By using advanced electron microscopy techniques energy-dispersive X-ray spectroscopy (EDX) tomography, both morphology elemental distribution irradiated can be disclosed, correlated detailed investigations their properties electromagnetic simulations. The wide variety species provided by proposed approach clear indication potential combining methods fs-pulsed for fabrication multielemental nanoparticles. resulting control over size composition raises promising prospects catalytic, plasmonic, magnetic applications multimetallic nanocrystals.