Robertson J, Hofmann S, Cantoro M, Parvez A, Ducati C, Zhong G, Sharma R, Mattevi C
Department of Engineering, University of Cambridge, Cambridge CB3 0FA, UK.
J Nanosci Nanotechnol. 2008 Nov;8(11):6105-11. doi: 10.1166/jnn.2008.sw08.
We have recently been able to grow single-walled carbon nanotubes by purely thermal chemical vapour deposition (CVD) at temperatures as low as 400 degrees C. This has been achieved by separating the catalyst pre-treatment step from the growth step. In the pre-treatment step, a thin film catalyst is re-arranged into a series of nano-droplets, which are then the active catalysts. Both steps have been studied by in-situ environmental transmission electron microscopy and X-ray photoemission spectroscopy. We have also studied the catalyst yield, the weight of nanotubes grown per weight of transition metal catalyst. Using very thin layers of Fe on Al2O3 support in a remote plasma-assisted CVD, we have achieved yields of order 100,000. This may be due to control of catalyst poisoning by ensuring an etching path.
我们最近能够通过纯热化学气相沉积（CVD）在低至400摄氏度的温度下生长单壁碳纳米管。这是通过将催化剂预处理步骤与生长步骤分开实现的。在预处理步骤中，将薄膜催化剂重新排列成一系列纳米液滴，这些纳米液滴随后成为活性催化剂。这两个步骤都通过原位环境透射电子显微镜和X射线光电子能谱进行了研究。我们还研究了催化剂产率，即每单位重量的过渡金属催化剂生长的纳米管重量。在远程等离子体辅助CVD中，使用在Al2O3载体上的非常薄的铁层，我们实现了约100,000的产率。这可能是由于通过确保蚀刻路径来控制催化剂中毒。
