Gold nanorod-seeded growth of silver nanostructures: from homogeneous coating to anisotropic coating.
Single crystalline gold nanorods (Au NRs) dominated by {110} side facets were employed as seeds to tailor the deposition of Ag. Apart from homogeneous coating, anisotropic coating of Ag was observed and resulted in an orange slice-like shape for the Au@Ag nanocrystal. Different growth rates for the {110} side facets were responsible for this shape: among the four {110} facets, two of the neighboring {110} facets grew more quickly and another two grew more slowly, thus inducing the anisotropic deposition of Ag around the Au NR. This growth behavior is believed to be a consequence of competition between the strong stabilization of cetyltrimethylammomium bromide (CTAB) molecules to the {110} facets of Ag and minimization of the overall surface energy. Although the reason for the anisotropic coating remains to be clarified, our results lead to one important conclusion: The interaction of CTAB and metal can be utilized to tune the shapes of bimetallic structures.
Xiang
Yanjuan
Y
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Graduate School of the Chinese Academy of Sciences, Beijing 100080, People's Republic of China.
Wu
Xiaochun
X
Liu
Dongfang
D
Li
Zhiyuan
Z
Chu
Weiguo
W
Feng
Lili
L
Zhang
Ke
K
Zhou
Weiya
W
Xie
Sishen
S
D000077286:Cetrimonium; D002593:Cetrimonium Compounds; D003460:Crystallization / Q000379:methods*; D006046:Gold; D053768:Metal Nanoparticles / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D043942:Nanotubes; D012834:Silver
D002593:Cetrimonium Compounds; D012834:Silver; D006046:Gold; D000077286:Cetrimonium