低压下酞菁裂解法制备定向碳纳米管阵列

Preparation of Vertically Aligned Carbon Nanotubes by Pyrolysis of Phthalocyanine at Lower Pressure

在低压条件下以酞菁铁为原料,采用独立双温控加热系统在石英玻璃基底上气相沉积制备了大面积准直性好和管径均匀的碳纳米管.利用扫描电子显微镜(SEM/FESEM)和透射电子显微镜(TEM)研究了定向碳纳米管的生长形态和结构.详细讨论了系统真空度、反应温度、气体流速及氢气和氩气的体积比例等参数对碳纳米管生长的影响,并测试了该碳纳米管的场发射性能及超电容性能.

Large scale vertically aligned carbon nanotubes（ACNTs） with a uniform length and diameter were prepared by the pyrolysis of iron （ Ⅱ ） phthalocyanine at a low pressure. The pyrolysis was performed in a dual furnace fitted with independent temperature controller. The morphology and microstructure of ACNTs were analyzed by SEM, FESEM and TEM. The ACNTs have a cylindrical and bamboo-like structure and are multiwalled carbon nanotubus. The influences of parameters such as gas pressure, growth temperature, gas flow rate and the volume ratio of Ar to H2 were studied. We foufid that ACNTs with best quality could been prepared at a pressure of 5 × 10^4 Pa and a higher temperature above 950 ℃. Some properties, such as field emission, capacitor, and sensor electrode of ACNTs were studied and discussed. The results showed a very powerful ability of electron emission with a lower turn-on voltage of 0.67 V · μm^-1 （ I = 1 μA） , a significant performance of power capacitor and electrical conductivity, which indicated that ACNTs are new highly efficient materials for practical devices application.