Comparison of nanotube structures constructed from α-, β-, and &gamma

2019-07-29 17:21:59

potential alpha beta gamma CYD

责任者: Ohira, Akihiro;Sakata, Masayo;Taniguchi, Isao;Hirayama, Chuichi;Kunitake, Masashi 单位: Department of Applied Chemistry, Faculty of Engineering, Kumamoto University, Kumamoto 860-8555, Japan 来源出处: Journal of the American Chemical Society,2003,125(17):5057-5065 摘要: Nanotube structures of the α-, β-, and γ-cyclodextrins (CyDs), which are similar to that of CyD-polyrotaxane, were constructed by potential-controlled adsorption onto Au(111) surfaces in sodium perchlorate solution without a threaded polymer. CyD molecules adsorbed randomly on bare Au(111) surfaces without potential control and the desorption of CyDs from Au surfaces was observed at a negative potential of less than -0.60 V versus SCE. On the other hand, in the specific range between these potentials, ordered molecular arrays with nanotube structures of the CyDs (α-, β-, and γ-CyD) were observed on Au(111). The range of potentials for formation of the nanotube structures of α-, β-, and γ-CyD was from -0.15 to -0.20 V, from -0.25 to -0.45 V, and from -0.22 to -0.45 V, respectively. β- and γ-CyD require a more negative potential for adsorption-induced self-organization (AISO) than α-CyD in order to weaken adsorption and induce self-organization. Furthermore, we have succeeded in the visualization of the dynamic process in solution, such as the self-ordering, and the destruction of the nanotube structure. These results indicate that control of the electrode potential facilitates management of the delicate balance of various interactions, resulting in the formation of two-dimensional supramolecular structures on the substrates. 关键词: Nanotubes;Adsorption;Polymers;Desorption;Electrodes;Supramolecular chemistry;Molecular arrays