碳纳米管是一种性能优良的场发射冷阴极材料,具有低的阈值电场和高的发射电流密度,在平板显示领域具有广阔的应用前景。本文从Fow ler-Nordhe im s场发射理论出发,阐述了CNT的场发射机制,详细论述了包括CNT的结构、方向性、阵列密度、吸附气体、工作环境等诸多因素对其场发射特性的影响。研究表明,垂直取向,长径比高,密度适中,表面洁净的CNT场增强因子较大,场发射性能较好。
Different shapes of ZnO nanobelts were synthesized at 550 ℃ by zinc acetate[Zn(CH3COO)2] and polyvinyl alcohol（PVA） as row material,under controlling the temperature rise rate.The analytical results of SEM and TEM indicate that the ZnO nanobelts possess a hexagonal wurtzite structure with preferred orientation along the direction of ZnO.For different experimental parameters,ZnO nanobelts have different widths and scales. The effect on zinc oxide nanobelts dimension and shape of proportion of mixture of raw material and mixing condition were discussed.Preliminary growth mechanics of ZnO nanobelts was proposed.
