摘要
石墨烯纳米片特殊的一维刀口状尖端赋予了其优异的电子场发射性能,而电场增强因子β是评价场发射性能的最重要参数,主要采用测定F-N曲线的实验方法进行推算.建立了形状为矩形薄片+半圆圆柱的石墨烯纳米片模型,竖直立于平行平板二极管的阴极上,利用电子束模拟软件EBS(Electron BeamSimulation)模拟计算了场发射装置的两极间的电场分布,由此决定石墨烯纳米片尖端的电场增强系数.研究了高度和顶端曲率半径变化对石墨烯纳米片电场增强因子的影响,根据计算数值拟合了电场增强系数的经验公式,提供了受形状控制的电场增强因子的数值范围,还与同尺寸的碳纳米管进行了比较,证实了本文的模型和计算模拟方法有效、可信.
Graphene nano flake（GNF） features properties of electron emission due to its one-dimensional sharp edge.Field enhancement factor β is an important parameter for emission evaluation,which is usually obtained by F-N curve measurement.In this paper,the field enhancement at the end of a single GNF vertical to the plate was calculated with the software of Electron Beam Simulation（EBS）.By polynomial regression and fit of the calculation data,an empirical expression was drawn.The effects of the height and edge curvature of the GNF on β were investigated.The efficient range of the GNF as a good emitter was studied.By comparing the GNT the CNT with the similar size,it was proved feasibility of the proposed model and calculation.
出处
《中北大学学报（自然科学版）》
CAS
北大核心
2012年第2期207-210,215,共5页
Journal of North University of China(Natural Science Edition)
基金
国家自然科学基金资助项目(50875207)
关键词
石墨烯纳米片
电场增强因子
数值模拟
场发射
graphene nanoflake
field enhancement factor
numerical simulation
field emission
