Water dynamics inside single-wall carbon nanotubes: NMR observations
Water dynamics inside single-wall carbon nanotubes: NMR observations
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DOI：
10.1103/physrevb.74.073415
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发表时间：
2006-08
影响因子：
3.7
通讯作者：
K. Matsuda;T. Hibi;H. Kadowaki;H. Kataura;Y. Maniwa
中科院分区：
文献类型：
--
作者：
K. Matsuda;T. Hibi;H. Kadowaki;H. Kataura;Y. Maniwa
用核磁共振方法研究了平均直径为$13.5\phantom{\rule{0.3em}{0ex}}\mathrm{\AA{}}$的单壁碳纳米管(SWCNT)中水分子(MATHROM{H})和MATHROM{O}分子在100~300美元范围内的吸附动力学.规则{0.3em}{0ex}}\mathm{K}$。在$220\phantom{0.3em}{0ex}}\mathm{K}$以上，核磁共振谱显著变窄，表明水处于类液体状态，具有平移和准自由旋转运动。当水在碳纳米管内部呈现长程有序性时，在${10}^{\ensuremath{-}6}\phantom{\rule{0.3em}{0ex}}\mathrm{s}$，的时间尺度内，大幅度的分子运动开始冻结，而低于120美元的幻影，几乎所有的质子都固定在每个原子位周围。计算结果支持了先前分子动力学计算所预测的动力学性质和冰-纳米管转变。
The dynamics of water (${\mathrm{H}}_{2}\mathrm{O}$ and ${\mathrm{D}}_{2}\mathrm{O}$) molecules adsorbed inside single-wall carbon nanotubes (SWCNTs) of average diameter $13.5\phantom{\rule{0.3em}{0ex}}\mathrm{\AA{}}$ were investigated by means of $^{2}\mathrm{H}$- and $^{1}\mathrm{H}$-NMR between 100 and $300\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. Above $220\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, the NMR spectra were substantially narrowed, and indicated that the water is in a liquidlike state with translational and quasifree rotational motions. Below $220\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, where water exhibits long range order inside SWCNTs, the large amplitude molecular motions start to freeze within a time scale of ${10}^{\ensuremath{-}6}\phantom{\rule{0.3em}{0ex}}\mathrm{s}$, while below around $120\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, almost all of the protons become fixed around each atomic site. The results support the dynamic properties and ice-nanotube transition predicted by previous molecular dynamics calculations.