Utilization of laser ablation in aqueous solution for observation of photoinduced shape conversion of silver nanoparticles in citrate solutions

Photoinduced shape conversion of silver nanoparticles in citrate solutions was examined using silver nanoparticles prepared by laser ablation. Nowadays, photoinduced shape conversion of silver nanoparticles in citrate solution attracts much attention as a novel technique to produce anisotropic-shaped nanocrystals in a simple manner. So far, the observations of the shape conversion have been carried out using source silver nanoparticles prepared by chemical synthesis. In this work, we demonstrate that silver nanoparticles prepared by laser ablation in liquids are an appropriate system to investigate the photoinduced shape conversion due to the simple preparation method and absence of unnecessary components in colloidal solution. Using this system, we have confirmed that particle size plays a critical role in the shape conversion. In addition, some novel information was obtained: the adsorption conditions of citrate are also important, and polyvinylpyrrolidone promote the conversion rate. (C) 2011 Elsevier B.V. All rights reserved.