低电阻率多壁碳纳米管粉体的制备和表征

Preparation and characterization of multiwalled carbon nanotube with low resistivity

利用高温空气氧化处理和酸洗相结合的工艺对多壁碳纳米管进行提纯,提纯后粉体经过SEM和热重表征(TGA)证明基本上消除了多壁碳纳米管中的金属催化剂粒子和无定形碳等杂质,碳纳米管纯度得到大幅度提升。随后在纯化后的多壁碳纳米管表面进行卤族元素的热掺杂,制备得到卤素掺杂多壁碳纳米管粉体。结果表明:经卤族元素的掺杂后,多壁碳纳米管粉体表面含有双卤族元素(Cl、I)。通过对各阶段粉体进行方片电阻测量发现:原始多壁碳纳米管电阻为9?,提纯后多壁碳纳米管电阻为5.7?;经卤素掺杂后多壁碳纳米管电阻为3?,电阻明显下降,经过各阶段处理后最终多壁碳纳米管电阻较原始多壁碳纳米管电阻降低66.7%。

Purified multiwalled carbon nanotubes were prepared by the combinative technology of high temperature air oxidation treatment and acid pickling. Metal catalyst particles and amorphous carbon were mostly removed by the representation of SEM and TGA, resulting in a high purity of the purified multiwalled carbon nanotubes. Subsequently, the surfaces of purified multiwalled carbon nanotubes were doped by halogen elements through high temperature diffusion to obtain the doped multiwalled carbon nanotubes. The results show that Cl and I elements are detected on the surfaces of the doped multiwalled carbon nanotubes. The resistances of pristine MWCNT, purified MWCNT and halogen doped MWCNT are 9Ω, 5.7Ω and 3Ω, respectively, through testing their square slice resistance, their resistances obviously decrease, reducing to 66.7% of that of the original multiwalled carbon nanotube.