常压下电弧法合成无定型纳米碳管和纳米碳纤维(英文)

Formation of Amorphous Carbon Nanotubes and Nanofibers at Atmospheric Pressure by Arc Discharge

以镍为催化剂,在常压条件下,乙炔和氦气气氛中,利用电弧法合成无定型纳米碳管(ACNT)和纳米碳纤维(ACNF)。采用透射电镜(TEM)和拉曼光谱(Raman)对产物进行表征,并采用发射光谱(OES)对等离子体的形成过程进行在线诊断。TEM电镜观察结果表,ACNT和ACNF的直径在60～100 nm之间,而且ACNF可能转化成ACNT。Raman分析结果表明,阴极上形成的ACNT的石墨化程度要高于阳极上形成的ACNT或ACNF。OES结果表明,等离子体中有C2和CH活性物种生成,它们可能是形成ACNT和ACNF的前驱体。

Amorphous carbon nanotubes （ACNTs） and amorphous carbon nanofibers （ACNFs） were synthesized at atmospheric pressure with Ni as catalyst in the medium of C2H2 and He by arc discharge. The microstructure of ACNTs and ACNFs was characterized by transmission electronic microscopy （TEM） and Raman spectroscopy. The plasma was diagnosed in situ by optical emission spectroscopy （OES） to investigate the formation process of ACNTs. The TEM observation results show that the diameter of ACNTs as well as ACNFs is in the range of 60- 100 nm and ACNFs can become ACNTs. Raman analysis results reveal the amorphous nature of ACNTs and ACNFs. The graphitization degree of ACNTs from the cathode is higher than that of ACNTs or ACNFs from the anode. The OES analysis shows that C2 and CH species might be the precursors for the formation of ACNTs and ACNFs.