大面积N-掺杂定向碳纳米管阵列的制备与表征

The Fabrication and Characterization of N-doped Aligned Carbon Nanotube Arrays in Large Area

采用无模板的化学气相沉积(chemicalvapourdeposition,CVD)法,以二甲苯和乙二胺为反应物,二茂铁为催化剂,以石英玻璃为衬底,制备了大面积、垂直于石英衬底生长、掺杂N的定向碳纳米管阵列。扫描电镜检测表明制备的定向碳纳米管阵列具有很好的定向性,而且管身平直。高分辨透射电镜的检测表明制备的碳纳米管具有较好的石墨化程度和较高的纯度,首次在碳纳米管内腔中发现了原位生长的“类富勒烯”结构。拉曼光谱的检测表明制备的定向碳纳米管阵列中含有大量的单壁碳纳米管。X射线光电子能谱检测表明N原子成功地被掺进了碳纳米管中,而且N原子的百分比随着碳源中N原子浓度的增加而增加,当碳源中nC∶nN比为1∶1的时候,在掺杂的碳纳米管中N原子的物质的量分数可以达到2.51%。

Large-area N-doped aligned carbon nanotube (ACNT) arrays perpendicular to the quartz substrate were synthesized by the chemical vapor deposition method (CVD) without template. Xylene and Ethylenediamine were selected as carbon and nitrogen feedstock respectively. Ferrocene was taken as the catalyst. Scanning electron microscopy (SEM) characterizations showed that the highly aligned synthesized ACNT arrays were composed of fairly straight carbon nanotubes with good graphite structures and high purity as confirmed by high resolution transmission electron microscopy (HRTEM) characterizations. Moreover, HRTEM characterizations also revealed the in-situ growth of 'fullerene-like' structure in the carbon nanotubes for the first time. Raman spectrum revealed abundant single-walled carbon nanotubes in the ACNT arrays. X-ray photoelectron spectrum characterizations showed that N atom was incorporated in the ACNT arrays successfully and its percentage increased with the increase of nitrogen source in the feedstock. When the mole ratio of the N atom to C atom was equal to 1:1, the incorporated N atoms in the ACNT arrays could reach as high as 2.51% in mole unit.