碳纳米管阵列的气相沉积制备及场发射特性

运用酞菁铁热解法气相沉积制备了碳纳米管阵列.所得碳纳米管呈多壁结构.单根碳纳米管的平均直径约为25 nm，长度约4～5 μm，且具有很好的准直性.研究了碳纳米管阵列的平面场发射特性，相应的开启电压和阈值电压分别为1.28和2.3 V•μm－1，表明碳纳米管具有很强的场发射能力.利用场发射显微镜观察了碳纳米管阵列的场发射像，发现碳纳米管阵列的场发射主要集中在样品薄膜的边缘部位.这是由于碳纳米管密度过大而产生的屏蔽效应所致.

Fabrication of Aligned Carbon Nanotubes by a Vapor-phase Deposition Technique and Their Field Emission Properties

Well-aligned carbon nanotubes with multiwall structure were fabricated by using a vapor-phase deposition technique based on the pyrolysis of iron phthalocyanine. The average diameter of single nanotube is about 25 nm, and the length of each is from 4 to 5 μm. The result of measure on the planar field emission of the aligned carbon nanotubes shows a very powerful ability of as-synthesized carbon nanotubes in the field emission with a turn-on voltage of 1.28 V•μm－1 and a threshold voltage of 2.3 V•μm－1. The field emission image of the aligned carbon nanotubes was also observed through using a field emission microscope, and it was found that the field emission of the carbon nanotubes was mainly centered on the edge of the thin film sample, which was attributed to the screening effect caused by the overlarge density of the carbon nanotubes.