基于铜催化的无定形碳纳米管制备及场发射特性研究

Preparation and field emission characteristics of amorphous carbon nanotube based on copper catalysis

采用化学气相沉积法(CVD)以酞菁铜(CuPc)为催化剂、甲烷为碳源在二氧化硅(SiO_2)基底上合成了碳纳米管薄膜(CNTs),经过扫描电镜(SEM)表征发现,合成的碳纳米管外径较大,范围约在140~280nm,长度约在10μm以上。拉曼光谱分析表明合成的碳纳米管为无定形(α-CNTs)结构。通过透射电镜(TEM)可以看出所制备α-CNTs管内中空,管壁厚度不均匀,约为20~100nm。采用二极管结构,在真空室中真空度为2×10-4 Pa时进行了场发射特性测试,测试结果表明SiO_2(α-CNTs)薄膜的场发射开启场强为1.05V/μm。通过计算得出薄膜的场增强因子为1.32×104,结果表明SiO_2(α-CNTs)具有良好的场发射特性。

The carbon nanotubes（CNTs）were synthesized on silica（SiO2）substrate by chemical vapor deposition（CVD）,used copper phthalocyanine（CuPc）as catalyst and methane as carbon source.The carbon nanotubes were characterized by field emission type scanning electron microscope（SEM）,raman spectra and transmission electron microscope（TEM）.The results showed that the carbon nanotubes had large outer diameter（140~280nm）,the length of about 10μm.The synthesized carbon nanotubes were amorphous nanotubes（α-CNTs）structure.It had a hollow structure and the tube wall thickness was not uniform,the range about 20 to 100nm.The field emission measurement was implemented with a diode structure in a vacuum chamber.The vacuum degree was 2×10-4Pa.The result shows SiO2（α-CNTs）turn-on field electric intensity was 1.05V/μm.The field enhancement factor was 1.32×104,It showed that SiO2（α-CNTs）had good field emission property.