Cooperative interactions among CTA+, Br– and Ag+ during seeded growth of gold nanorods
gold nanorods, anisotropic nanostructure, surface plasmon resonance, seeded growth, cetyltrimethyl ammonium bromide (CTAB)
ABSTRACT We have carried out a comprehensive study on the formation mechanism of Au nanorods (AuNRs) in binary surfactant mixtures composed of quaternary ammonium halide and sodium oleate (NaOL). We identify the cetyltrimethyl ammonium (CTA)-Br-Ag+ complex as the key ingredient in directing the anisotropic growth of AuNRs. Based on the improved understanding of the cooperative interactions among CTA+, Br– and Ag+, we further demonstrate that AgBr, which is readily solubilized by the cetyltrimethyl ammonium bromide (CTAB) or cetyltrimethyl ammonium chloride (CTAC) micelles, can be employed as the combined source of Ag+ and Br– for the preparation of AuNRs. The growth of high-quality AuNRs can be completed within 15 min under extremely low bromide content (0.1 mM).
Tsinghua University Press
Yong Xu,Lei Chen,Xingchen Ye,Xuchun Wang,Jiaqi Yu,Yang Zhao,Muhan Cao,Zhouhui Xia,Baoquan Sun,Qiao Zhang, Cooperative interactions among CTA+, Br– and Ag+ during seeded growth of gold nanorods. NanoRes.2017, 10(6): 2146–2155