Pan Xiulian, Fan Zhongli, Chen Wei, Ding Yunjie, Luo Hongyuan, Bao Xinhe
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023, PR China.
Nat Mater. 2007 Jul;6(7):507-11. doi: 10.1038/nmat1916. Epub 2007 May 21.
Carbon nanotubes (CNTs) have well-defined hollow interiors and exhibit unusual mechanical and thermal stability as well as electron conductivity. This opens intriguing possibilities to introduce other matter into the cavities, which may lead to nanocomposite materials with interesting properties or behaviour different from the bulk. Here, we report a striking enhancement of the catalytic activity of Rh particles confined inside nanotubes for the conversion of CO and H2 to ethanol. The overall formation rate of ethanol (30.0 mol mol(-1)Rh h(-1)) inside the nanotubes exceeds that on the outside of the nanotubes by more than an order of magnitude, although the latter is much more accessible. Such an effect with synergetic confinement has not been observed before in catalysis involving CNTs. We believe that our discovery may be of a quite general nature and could apply to many other processes. It is anticipated that this will motivate theoretical and experimental studies to further the fundamental understanding of the host-guest interaction within carbon and other nanotube systems.
碳纳米管（CNTs）具有明确的中空内部结构，并展现出非凡的机械稳定性、热稳定性以及电子导电性。这为将其他物质引入其空腔开辟了引人入胜的可能性，进而可能产生具有有趣特性或不同于整体材料行为的纳米复合材料。在此，我们报道了限制在纳米管内部的铑颗粒对于一氧化碳和氢气转化为乙醇的催化活性有显著增强。尽管纳米管外部更容易接触反应物，但纳米管内部乙醇的总生成速率（30.0 mol mol⁻¹Rh h⁻¹）比纳米管外部高出一个多数量级。在涉及碳纳米管的催化过程中，这种具有协同限制作用的效应此前尚未被观察到。我们相信我们的发现可能具有相当普遍的性质，并且可能适用于许多其他过程。预计这将激发理论和实验研究，以进一步深入理解碳及其他纳米管系统中的主客体相互作用。
