Gold-spiked coating of silver particles through cold nanowelding

Herein, we present a method to obtain particles composed of a segregated alloy of silver coated with gold. These particles are achieved through the controlled Ostwald ripening of small gold nanoparticles (NPs) on the surfaces of larger silver particles. The prepared segregated nanoalloyed colloids benefit from the advantages of gold and silver with none of their drawbacks. These platforms provide optical efficiencies which are superior to those of silver with the chemical resistance and biocompatibility of gold.