Confined propagation of covalent chemical reactions on single-walled carbon nanotubes
Confined propagation of covalent chemical reactions on single-walled carbon nanotubes
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DOI：
10.1038/ncomms1384
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发表时间：
2011-07-01
影响因子：
16.6
通讯作者：
Wang, YuHuang
中科院分区：
文献类型：
--
作者：
Deng, Shunliu;Zhang, Yin;Wang, YuHuang
共价化学通常在碳纳米管的石墨烯晶格上随机发生，因为电子在数千个原子位置上离域，并迅速破坏纳米管的电学和光学性质。在这里，我们表明，比卢普斯-伯奇还原烷基化，近百年历史的伯奇还原的变体，发生在单壁碳纳米管上的缺陷激活和传播完全从sp（3）缺陷网站，估计概率超过1,300倍，否则随机键合到“π电子海”。这种机制迅速导致反应前沿在管状方向上的限制。限制引起了一系列有趣的现象，包括聚集分布的官能团和恒定的传播速率为18 +/- 6纳米每个反应周期，允许直接控制的空间图案的功能团在纳米长度尺度上。
Covalent chemistry typically occurs randomly on the graphene lattice of a carbon nanotube because electrons are delocalized over thousands of atomic sites, and rapidly destroys the electrical and optical properties of the nanotube. Here we show that the Billups-Birch reductive alkylation, a variant of the nearly century-old Birch reduction, occurs on single-walled carbon nanotubes by defect activation and propagates exclusively from sp(3) defect sites, with an estimated probability more than 1,300 times higher than otherwise random bonding to the 'pi-electron sea'. This mechanism quickly leads to confinement of the reaction fronts in the tubular direction. The confinement gives rise to a series of interesting phenomena, including clustered distributions of the functional groups and a constant propagation rate of 18 +/- 6 nm per reaction cycle that allows straightforward control of the spatial pattern of functional groups on the nanometre length scale.