双壁碳纳米管的电子显微学研究  

An electron microscopy study of double-walled carbon nanotubes

作　　者：张婧娉[1] HAKAN Deniz 秦禄昌 刘庆丰[1] 任文才[1] 成会明[1] 

机构地区：[1]中国科学院金属研究所沈阳材料科学国家(联合)实验室 [2]W M Keck Laboratory for Atomic Imaging and Manipulation,University of North Carolina at Chapel Hill,Chapel Hill,NC 27599-3255,USA

出　　处：《电子显微学报》2007年第4期327-334,共8页Journal of Chinese Electron Microscopy Society

摘　　要：本文分析研究了甲酸镍二水合物作为催化剂前驱体,多壁管为原料,采用氢电弧放电法制得的双壁碳纳米管样品中不同管壁数目碳纳米管的分布及双壁碳管直径分布,发现样品中单壁和双壁碳管占主要地位,双壁管的内径主要分布在1.67 nm^3.67 nm之间,外径主要分布在2.33 nm^4.33 nm之间。此外,精确测定了三个双壁碳纳米管的螺旋指数,分别为[(28,3)(29,17)],[(19,8)(29,6)]及[(23,15)(28,22)],其电学性能分别为[半导体性,金属性],[半导体性,半导体性]及[半导体性,金属性]。同时,观察了在不同条件下的电子辐照效应。结果表明,经辐照碳管的最内层管壁先发生断裂,其形变速度逐渐变慢,单根碳管易依附于大块物质。在相同的辐照条件下,管壁数目越多碳管越稳定。当管壁数目相同时,直径小的管比直径大的管稳定。高加速电压能够加速碳管的变形。In this paper, the diameter distribution of 270 double-walled carbon nanotubes （DWNTs） and the distributions of 602 carbon nanotubes selected randomly with different number of shells in a carbon nanotube sample were examined. It was found that the single-walled carbon nanotubes （SWNTs） and DWNTs are dominant in the specimen. The inner tube diameter and the outer tube diameter of the DWNTs ranged from 1.67 to 3.67 nm and 2.33 to 4.33 nm, respectively. In addition, the chiral indices of three DWNTs were determined using electron diffraction： they were [（28, 3） （29, 17）], [（19, 8） （29, 6）] and [（23, 15） （28, 22）], respectively. Their respective metallicity was [semiconducting, metallic], [semiconducting, semiconducting], and [semiconducting, metallic]. When the composing shells of DWNTs was te in the axial direction, the electron diffraction patterns had 2mm symmetry, and the scattering distribution on each layer line can could described as a single Bessel function Jn . The irradiation effects in both SWNTs and DWNTs under 200 kV and 300 kV electron beam were also examined to reveal the structural collapse of the nanotubes. It was observed that the innermost shell of a carbon nanotube （CNT） would break firstly and the deformation slowed down after several minutes of irradiation. Under the same irradiation conditions, the CNTs showed a higher stability when they have more shells, smaller tube diameters, lower acceleration voltage and lower beam current density.

关 键 词：碳纳米管 透射电子显微术 电子衍射 电子辐照 螺旋度 

分 类 号：TB383.1[一般工业技术—材料科学与工程]