单壁碳纳米管的场发射特性研究

A study on field emission patterns of single-walled carbon nanotubes

利用场发射显微镜 (FEM)和四极质谱计分别研究了经过热处理的单壁碳纳米管的场发射图像和热处理过程中样品脱附的残气质谱 .当热处理温度达到 10 0 0℃左右时得到了单壁碳纳米管的场发射像 ,此像可能是顶端开口的单根 (16 ,0 )锯齿形单壁碳纳米管的具有原子可分辨的场发射图像 .四极质谱分析结果表明 ,在此温度范围W针尖晶粒间隙中有O原子和C原子释放出来 .它们对单壁碳纳米管顶端的修饰是我们能观察到这些碳纳米管场发射像的可能原因 .

Field emission patterns of single-walled carbon nanotubes (SWCNTs) were studied using the field emission microscopy (FEM) Mass spectra of desorbed residual gases were monitored with a quadruple mass spectrometer during processes of thermal treatment. After SWCNTs were treated at about 1000degreesC, the obtained field emission patterns were possibly atomically resolved, which might be produced by a (16,0) zigzag SWCNT without cap. Results of mass spectra indicated that oxygen and carbon atoms were mainly released from the polycrystal tungsten tip at higher temperatures. The ends of SWCNTs could be modified by these atoms,which might be the reason that these field emission patterns of SWCNTs could be observed.