title: Stepwise Preparation of Spherical Gold Nanoparticles Passivated with Cationic Amphiphiles.
abstract: Spherical gold nanoparticles with cationic surfaces were prepared in hexadecyltrimethylammonium (CTA(+)) chloride (CTAC) and CTA(+) bromide (CTAB) solutions. In a CTAC solution, ascorbic acid reduction of gold ions (AuCl4(-)) induced spontaneous nucleation of gold clusters, which resulted in the formation of small gold nanoparticles (<5 nm). In a CTAB solution, the combination of ascorbic acid and AuBr4(-) induced low spontaneous nucleation, and therefore controllable crystal growth of seed particles was possible. To obtain uniform gold nanoparticles, seed particles (<5 nm) were first prepared in a CTAC solution using NaBH4 as a reducing agent. Subsequent growth reactions of the seeds in CTAB solutions were controllable to obtain gold nanoparticles with diameters ranging from 7 to 60 nm.
authors: Department of Chemistry and Bioscience, Graduate School of Science and Engineering, Kagoshima University.
authors: Yuki
authors: Y
authors: Inoue
authors: Yo
authors: Y
authors: Tsutamoto
authors: Daiki
authors: D
authors: Muko
authors: Kazuaki
authors: K
authors: Nanamura
authors: Tsuyoshi
authors: T
authors: Sawada
authors: Yasuro
authors: Y
authors: Niidome