Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, Lindfield, New South Wales, 2070, Australia.
Nanoscale. 2011 Aug;3(8):3214-20. doi: 10.1039/c1nr10327j. Epub 2011 Jun 24.
Controlled synthesis of both single-walled carbon nanotube and carbon nanowire networks using the same CVD reactor and Fe/Al(2)O(3) catalyst by slightly altering the hydrogenation and temperature conditions is demonstrated. Structural, bonding and electrical characterization using SEM, TEM, Raman spectroscopy, and temperature-dependent resistivity measurements suggest that the nanotubes are of a high quality and a large fraction (well above the common 33% and possibly up to 75%) of them are metallic. On the other hand, the carbon nanowires are amorphous and semiconducting and feature a controlled sp(2)/sp(3) ratio. The growth mechanism which is based on the catalyst nanoisland analysis by AFM and takes into account the hydrogenation and temperature control effects explains the observed switch-over of the nanostructure growth modes. These results are important to achieve the ultimate control of chirality, structure, and conductivity of one-dimensional all-carbon networks.
通过略微改变氢气和温度条件，使用相同的 CVD 反应器和 Fe/Al(2)O(3)催化剂，成功地控制合成了单壁碳纳米管和碳纳米线网络。使用 SEM、TEM、拉曼光谱和温度相关电阻测量对结构、键合和电特性进行的研究表明，这些纳米管的质量很高，其中很大一部分（远高于常见的 33%，甚至可能高达 75%）是金属的。另一方面，碳纳米线是无定形的半导体，具有可控的 sp(2)/sp(3) 比。该生长机制基于 AFM 对催化剂纳米岛的分析，并考虑了氢气和温度控制的影响，解释了观察到的纳米结构生长模式的转换。这些结果对于实现一维全碳网络的手性、结构和导电性的最终控制非常重要。
