【摘要】 利用范氏力将单壁碳纳米管样品组装到钨针尖上 ,用FEM/FIM对同一碳纳米管样品用热处理方法和场脱附方法进行了研究。场离子显微镜是具有原子级分辨能力的尖端表面分析工具 ,由场离子像推测这次组装的样品是由三根单壁碳纳米管突起组成的碳纳米管束。清洁碳纳米管束样品的场发射像和场离子像有极好的对应关系。场脱附后的碳纳米管束的场发射特性较好地符合Fowler Nordheim场发射模型。通过比较碳纳米管束吸附态和热处理后以及场脱附后的Fowler Nordheim曲线的斜率变化 ,得出碳纳米管束样品逸出功的变化 ,再结合场发射像的变化推断出场脱附与热处理结合是一种较理想的获得清洁碳纳米管表面的方法更多还原

【Abstract】 We assembled SWCNTs onto tungsten tips via Van der Waals force.The influence of heat treatment and field desorption on these SWCNTs was studied using a field emission microscope(FEM) and a field ion microscope(FIM),respectively.The obtained FIM images are believed to result from a thin bundle consisting of three individual SWCNTs.FEM images from clean state of the same sample were in very good agreement with its FIM images.After field desorption,field emission from SWCNTs followed the Fowler Nordheim equation more strictly.The change in the slope of Fowler Nordheim plots revealed that the heat treatment and field desorption resulted in changes of work function of the SWCNTs. This change in work function,as well as changes in FEM/FIM images, showed that a combination of heat treatment and field desorption may be a feasible way to obtain clean carbon nanotubes with better field emission properties.更多还原