Lin Ming, Ying Tan Joyce Pei, Boothroyd Chris, Loh Kian Ping, Tok Eng Soon, Foo Yong-Lim
Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602.
Nano Lett. 2006 Mar;6(3):449-52. doi: 10.1021/nl052356k.
The growth dynamics of a single-walled carbon nanotube (SWNT) is observed in real-time using an in situ ultrahigh vacuum transmission electron microscope at 650 degrees C. SWNTs preferentially grow on smaller sized catalyst particles (diameter <or= 6 nm) with three distinct growth regimes (incubation, growth, and passivation). All of the observed SWNTs grow via a base-growth mechanism with C diffusion on active Ni catalyst sites. Under the same experimental conditions, formation of carbon nanocages was observed on larger Ni catalyst particles. The evolution of SWNTs or nanocages is dependent on catalyst size, and this can be rationalized from both energetics and kinetics considerations.
在650摄氏度下，使用原位超高真空透射电子显微镜实时观察单壁碳纳米管（SWNT）的生长动力学。单壁碳纳米管优先在尺寸较小的催化剂颗粒（直径≤6纳米）上生长，具有三种不同的生长模式（潜伏期、生长期和钝化期）。所有观察到的单壁碳纳米管均通过在活性镍催化剂位点上的碳扩散，以基生长机制生长。在相同的实验条件下，在较大的镍催化剂颗粒上观察到了碳纳米笼的形成。单壁碳纳米管或碳纳米笼的演变取决于催化剂尺寸，这可以从能量学和动力学两方面进行合理解释。
