不锈钢衬底碳纳米管薄膜的场发射特性

Field Emission Properties of Carbon Nanotubes Films on Stainless Steel Substrates

不需要添加任何催化剂,直接在含有少量Ni和Cr成分的不锈钢衬底上,用微波等离子体化学气相沉积(MPCVD)方法沉积碳纳米管薄膜.在SEM下观察,生成的碳纳米管取向无序,但浓度大、杂质含量少、直径小且分布均匀,其直径在50-60nm,为多壁碳纳米管.Raman光谱实验证实了此碳纳米管中存在大量缺陷.场发射实验表明,本样品的开启电压低,电子发射均匀,发射电流大.当用ITO玻璃作阳极且场强为11 V/μm时,电流密度可达到31 mA/cm2;当用荧光粉包覆的ITO玻璃作阳极且场强为6 V/μm时,电流密度可达到1.25 mA/cm2,这时的电子可稳定发射,使该样品变成良好的电子发射体.

Carbon nanotubes (CNTs) are synthesized from methane and hydrogen gas mixture directly on stainless steel plates by microwave plasma chemical vapor deposition (MWPCVD). The SEM images show that the CNTs are of uniform with high density and lest amorphous carbon quantity, and their diameters are ranged from 50 to 60 nm. They are multi-wall nanotubes. The Raman spectrum shows more defect density in nanotube . In the field emission test , when anode is made of an ITO coated glass plate, the current density of sample attains 31 mA/cm2 at the electric field of 11 V/μm, but when anode is made of coating phosphor onto an ITO coated glass plate, the current density attains 1. 25 mA/cm2 at the electric field of 11 V/μm. The CNTs film can be a good cold cathode fo'r flat panel display applications.