Adsorption of 1-Decyl-3-methylimidazolium Bromide and Solvation Structure of Bromide at the Air/Water Interface
Adsorption of 1-Decyl-3-methylimidazolium Bromide and Solvation Structure of Bromide at the Air/Water Interface
复制标题
DOI：
10.2116/analsci.24.1279
复制
发表时间：
2008-10
影响因子：
1.6
通讯作者：
M. Aratono;Kei Shimamoto;A. Onohara;D. Murakami;H. Tanida;I. Watanabe;T. Ozeki;H. Matsubara;T. Takiue
中科院分区：
文献类型：
--
作者：
M. Aratono;Kei Shimamoto;A. Onohara;D. Murakami;H. Tanida;I. Watanabe;T. Ozeki;H. Matsubara;T. Takiue
用表面张力测量和全反射条件下X射线吸收精细结构方法(TRXAFS)研究了1-癸基-3-甲基咪唑溴(DeMIMB)在空气/水界面的吸附膜。通过表面张力的测定，确定了离子的表面过剩浓度。XAFS测量发现，溴离子在吸附膜中有两种溶剂化状态，分别为“自由-BR”和“结合-BR”。前者的水化数估计为6，后者的水化数估计为4。基于XAFS分析的结果提供了有关吸附膜中区域形成的重要信息，最可能的情况是吸附的分子肯定不是均匀分散的，但区域(岛或簇)分散在吸附的膜中。可以在结构域中形成规则且相当紧密的咪唑环堆积。
The adsorbed film of 1-decyl-3-methylimidazolium bromide (DeMIMB) at the air/water interface was investigated employing the surface tension measurement and the x-ray absorption fine structure method under the total reflection condition (TRXAFS). From the surface tension measurement, the surface excess concentrations of ions were determined. From the XAFS measurement, two solvation states of bromide ion were found in the adsorbed film, which were assigned to be “free-Br” and “bound-Br”. The hydration number of the former was estimated to be 6 while that of the latter was estimated to be 4. The results based on the XAFS analysis provided significant information on the formation of domains in the adsorbed film; the most conceivable situation is that the adsorbed molecules are definitely not homogeneously dispersed, but domains (islands or clusters) are dispersed in the adsorbed film. A regular and rather tight stacking of immidazolium rings may be formed in the domains.