Fe-Mo/MgO催化剂CVD法制备碳纳米管

Preparation of Carbon Nanotube by CVD Method with Fe-Mo/MgO Catalyst

研究了Fe-Mo/MgO催化剂裂解乙炔制备碳纳米管的反应条件。结果表明,反应气氛对碳纳米管的生长具有明显的影响,在H2或Ar气氛下,所得碳纳米管的质量较差,而在N2-H2(1:1体积比)和Ar-H2(5.5:1体积比)气氛下乙炔裂解可制得纯度好、收率较高的碳纳米管。电镜观察发现在Ar-H2气氛下所制备碳纳米管的直径(平均直径为18nm)明显小于在N2-H2气氛下所制备碳纳米管(平均直径为30nm),这便于通过反应气氛的调节来控制碳纳米管的直径。用Fe-Mo/MgO做催化剂、乙炔为碳源,Ar-H2反应气氛下,850℃左右、反应30min所得碳纳米管的质量、产率最佳。

The effect of the preparation conditions on the carbon nanotube prepared with Fe-Mo/MgO as catalyst and acetylene as carbon resource by chemical vapor deposition (CVD) method was investigated. The results showed that the growth of carbon nanotubes is heavily influenced by the reaction ambience. The quality of CNTs prepared in N2-H2 or Ar-H2 ambience is better than that of prepared in H2 or Ar ambience. The outer diameter of CNTs prepared in Ar-H2 ambient is 18 nm, which is much smaller than that of CNTs prepared in N2-H2 ambience as 30nm. The CNTs prepared at around 850°C in Ar-H2 ambience, with Fe-Mo/MgO as catalyst and with acetylene as carbon resource is of high quality and high productivity.