Reduction and morphology of silver nanoparticles via liquid-liquid method

1-Hexanethiol-capped silver nanoparticles of about 10-20 nm in diameter were prepared using a liquid-liquid two-phase method. With the UV-Vis absorbance spectra, it was found that large particles were formed at the beginning of reaction and then disintegrated into small ones. In late reaction stage, the small particles became a bit larger with time and kept its size after 5 h, which was stable in 3 weeks. The reaction rate was strongly influenced by initial silver salt concentration in a first-order fashion and by reaction temperature. The transmission electron microscopy (TEM) images showed that size distribution and the morphology of fabricated alkylthiol-capped silver particles were different when they were prepared under different solvent, indicating that the reduction and capping process may depend on various solvents. (C) 2003 Elsevier B.V. All rights reserved.