Co-Mo/MgO催化剂上甲烷化学气相沉积制备高纯度多壁碳纳米管

Synthesis of high purity multiwalled carbon nanotubes over Co-Mo/ MgO catalyst by the catalytic chemical vapor deposition of methane

摘要: 以甲烷为碳源，Co-Mo/MgO为催化剂，通过气相化学沉积制备了直径均匀的多壁碳纳米管（MWCNTs）。采用溶胶－凝胶法所制双金属催化剂的组成为Co∶Mo∶MgO=5∶20∶75（质量比）。热重分析表明多壁碳纳米管产率高达313.67%。催化剂对于多壁碳纳米管生长的选择性是91.17%（其余为无定形碳）。透射电子显微镜分析显示：催化剂上生长的MWCNTs平均直径为6.2±0.5nm(平均±标准偏差)。通过稀酸的简单纯化处理，纯化样品的催化剂残存率降至0.72％。

Abstract: Nearly uniform diameter multiwalled carbon nanotubes (MWCNTs) were synthesized over a magnesia supported Co-Mo bimetallic catalyst through the catalytic chemical vapor deposition of methane. The bimetallic catalyst with a composition of Co∶Mo∶MgO=5∶20∶75 (mass ratio) was prepared by a sol-gel method. Thermagravimetric analysis shows that MWCNTs were synthesized in high yield. The selectivity of the catalyst for MWCNTs over undesired amorphous carbon was 91.17%. Transmission electron microscopy indicates that the MWCNTs grown on the catalyst have an average diameter of 6.2±0.5nm (mean±standard deviation). Through simple purification by mild acid treatment, the catalyst residue for the purified samples was reduced to 0.72%.