热化学气相沉积法在硅纳米丝上合成碳纳米管(英文)

Synthesis of carbon nanotubes on silicon nanowires by thermal chemical vapor deposition

利用热化学气相沉积法在负载不同厚度催化剂的硅纳米丝(SiNW)表面生长碳纳米管(CNTs),探讨了生长条件对所合成SiNW-CNT的结构和场发射特性的影响。这种类似树状的三维结构具有较高碳纳米管表面密度及降低的电场筛除效应等潜在优势。使用拉曼光谱(Raman)、电子显微镜(SEM)、透射电子显微镜(TEM)、能量扩散分光仪(EDS)分析了碳纳米管的结构性质,并在高真空下施加电场测得碳纳米管的场发射特性。结果表明:随硅纳米丝上负载催化剂镍膜厚度的变化,所合成碳纳米管的表面特性、结晶结构及功函数改变,导致电子发射难易程度的改变,进一步影响碳纳米管的场发射特性。

Carbon nanotubes（CNTs） were grown on a silicon nanowire substrate with Ni-catalyst layers of different thicknesses using thermal chemical vapor deposition.Scanning electron microscopy was used to observe the surface morphology,and Raman spectroscopy was used to investigate the structural changes in relation to the thicknesses of the catalyst deposited on the substrate.Field-emission characteristics of CNTs were also correlated with the catalyst thicknesses.The catalyst thickness was found to effectively change the field-emission characteristics of the CNTs.Obvious changes in the diameters,population density,and morphology of CNTs were found with differences in catalyst thickness.The field-emission characteristics of CNTs were dependent on their diameter.