Silver nanoparticles capped by oleylamine: formation, growth, and self-organization

Langmuir. 2007 May 8;23(10):5296-304. doi: 10.1021/la700553d. Epub 2007 Apr 11.


Nearly monodisperse silver nanoparticles have been prepared in a simple oleylamine-liquid paraffin system. Intensive study has found that the formation process of silver nanoparticles could be divided into three stages: growth, incubation, and Ostwald ripening stages. Ultraviolet-visible spectroscopy, transmission electron microscopy (TEM), and high-resolution TEM have all demonstrated the occurrence of Ostwald ripening, which could result in better control over the size and size distribution of silver nanoparticles. SAXS (small-angle X-ray scattering) results show that the as-obtained silver nanoparticles can self-assemble into ordered arrays. The possible reduction mechanism of silver ions by oleylamine is related to the Ag+-mediated conversion of primary amines to nitriles.