纳米材料微结构的原位电子显微学研究  

In Situ TEM Study of Nanostructures

作　　者：谭玉[1] 夏明霞[1] 李红星[1] 王岩国[1] 王岩国 

机构地区：[1]湖南大学微纳技术中心,长沙 410082 [2]中国科学院物理研究所,北京 100080

出　　处：《现代科学仪器》2008年第1期30-33,共4页Modern Scientific Instruments

基　　金：国家自然科学基金;项目批准号60571044;10774174。

摘　　要：利用电子显微学方法原位研究了外场作用下纳米材料的微结构稳定性,进行了微结构修饰和纳米材料间联结。结果显示外电场使多壁碳纳米管端部碳原子间的π键分解,外部碳原子与端部碳原子结合形成σ键。在端部电场的作用下,外部碳原子定向生长成非晶态碳纳米线,形成碳纳米管-纳米线复合结构。采用电子束诱导沉积的方法对二个多壁碳纳米管端部之间进行了焊接,实现了纳米材料间的几乎无损伤的联结。电子显微镜作为新纳米结构构建工具有位置选择精确、可实时监测、对纳米材料几乎无损伤、重复性和可靠性高,以及加工尺度可人为控制的优点。Stability and modification of nanomaterial＇ s microstructures as well as junction of the carbon nanotubes have been conducted using in situ transmission electron microscopy. π type bonds between the carbon atoms at the tip of carbon nanotube were broken by the applied voltage,σ bonds formed due to the foreign carbons incorporated into the tip of carbon nanotube and resulted in amorphous carbon nanowires initialized on the top of multi-walls carbon nanotube, orientational growth lead to the amorphous carbon nanowires with fr＇actal characteristic and the carbon nanotube-nanowire nanostructure. Solid junction between two carbon nanotubes has also been fabricated by in situ electron beam deposition. Buckling test showed that the weld junction with a strong me chanical binding between the two nanotubes formed an integrated structure. The advantage of in situ electron beam deposition is that joint dimension was determined by the size of electron beam, which results in a sound junction with the well-defined geometry and minimum junction size.

关 键 词：纳米结构 原位研究 电子显微学 

分 类 号：TB383.1[一般工业技术—材料科学与工程]