A one-dimensional network from the self-assembly of gold nanoparticles by a necklace-like polyelectrolyte template mediated by metallic ion coordination.
A new approach to one-dimensional organization of gold nanoparticles (2-4 nm) is described, using poly(4-vinylpyridine) (P4VP) molecular chain as a template with the mediation of free Cu2+ ion coordination. The assembly was conducted on freshly prepared mica surfaces and in aqueous solution, respectively. The surface assembly was characterized by tapping mode atomic force microscopy (AFM), observing the physisorbed molecules in their chain-like conformation with an average height of 0.4 nm. By the mediation of Cu2+ ions, gold nanoparticles modified by 3-mercaptopropionic acid were deposited onto the molecular chains, evidenced by a clear increase in height. Generation of the network in solution is time-dependent and pH reversible, characterized by UV-vis absorption spectra and transmission electron microscopy (TEM). No comparable network is obtained without Cu2+ ions, indicating the significance of ionic mediation. A mechanism for the self-assembly in solution is proposed, and the nature of the mediation of Cu2+ ions was identified by x-ray photoelectron spectroscopy (XPS).
Zhang
Jia
J
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, People's Republic of China.
Wang
Juan
J
Xu
Xiaowen
X
Zhu
Hui
H
Wang
Zhongjun
Z
Yang
Fan
F
Zhang
Bailin
B
Yang
Xiurong
X