The flower-like silver nanoparticles have been synthesized by reducing silver nitrate （AgNO3） with ascorbic acid （AA） as the reductant and polyvinyl pyrrolidone （PVP） as the capping agent under vigorous stirring...The flower-like silver nanoparticles have been synthesized by reducing silver nitrate （AgNO3） with ascorbic acid （AA） as the reductant and polyvinyl pyrrolidone （PVP） as the capping agent under vigorous stirring. Such flower-like nanoparticles are aggregates of small nanoplates and nanorods. They were tested as substrates for the surface-enhanced Raman scattering （SERS）, showing high sensitivity for detecting Rhodamine 6G （RBG） at a concentration as low as 10 7 mol/L. It has been found that replacing mechanical stirring with ultrasound sonication would drastically change the particle morphology, from flower-like nanoparticles to well-dispersed smaller nanoparticles. Furthermore, when trace amounts of NaC1 were added into the reagents, well-dispersed Ag nanoparticles formed even in vigorous stirring. These phenomena can be explained with the diffusion and reactant supply during nucleation and growth of Ag nanoparticles.展开更多
基金financial support for this work from the Natural Science Foundation for Young Scientists of Shanxi Province of China (No. 2015021078)International Cooperation of Science and Technology Project in Shanxi Province of China (No. 2014081006-2)
文摘The flower-like silver nanoparticles have been synthesized by reducing silver nitrate （AgNO3） with ascorbic acid （AA） as the reductant and polyvinyl pyrrolidone （PVP） as the capping agent under vigorous stirring. Such flower-like nanoparticles are aggregates of small nanoplates and nanorods. They were tested as substrates for the surface-enhanced Raman scattering （SERS）, showing high sensitivity for detecting Rhodamine 6G （RBG） at a concentration as low as 10 7 mol/L. It has been found that replacing mechanical stirring with ultrasound sonication would drastically change the particle morphology, from flower-like nanoparticles to well-dispersed smaller nanoparticles. Furthermore, when trace amounts of NaC1 were added into the reagents, well-dispersed Ag nanoparticles formed even in vigorous stirring. These phenomena can be explained with the diffusion and reactant supply during nucleation and growth of Ag nanoparticles.
