A plasma-based gas-phase method for synthesis of gold nanoparticles

There are many applications for gold nanoparticles (AuNPs) due to their interesting optoelectronic properties such as tunable optical absorption and plasmonic resonance behavior. Although synthesis and stabilization of colloidal AuNPs are well established, new synthesis routes can lead to enhanced versatility of applications for AuNPs, particularly if the methods allow avoidance of solution processes or surfactants. Here, we introduce a plasma-based synthesis of AuNPs, using a consumable gold wire and a radiofrequency power source. The AuNPs are monodisperse, with an average diameter of 4 nm. Although production yield is low, the narrow size distribution of the AuNPs and the avoidance of solution processing in this method are promising for future syntheses of metal NPs based on plasmas.