【摘要】 该文利用场发射显微镜对单壁碳纳米管的逸出功进行了研究和测量。未进行加热除气的单壁碳纳米管的表面吸附大量气体,此时测量的逸出功不是清洁表面单壁碳纳米管的逸出功。实验首先加热除气得到单壁碳纳米管的场发射清洁像,然后利用场发射显微镜测量I-V曲线,得到Fowler-Nordheim直线斜率;再利用透射电镜观测单壁碳纳米管微束形貌像,测量管束半径,通过三种公式估算比例因子β,最后计算得到单壁碳纳米管的逸出功。更多还原

【Abstract】 The work function of Single-Walled Carbon NanoTubes (SWCNTs) is investigated using Field Emission Microscopy (FEM). Since electron states of absorbed atoms and molecules dominate field emission from SWCNTs at room temperature, any measure prior to desorption could not obtain the work function of clean SWCNTs. So field emission patterns of clean SWCNTs are firstly achieved after SWCNTs are treated at high temperatures, then Ⅰ-Ⅴ behaviors of clean SWCNTs are measured. The radius of the bundle of SWCNTs is known from its image of Transmission Electron Microscopy (TEM) so that the ratio factor p could be calculated using 3 different formulas, hence the work function of clean SWCNTs is determined from the slope of Fowler-Nordheim plot.更多还原