摘要
本文采用基于密度泛函理论的第一性原理计算方法,研究了不同横截面氧化锌纳米线(ZnONW)的结构稳定性和场致发射特性。结果表明:ZnONW的直径越大,原子弛豫后Zn-O键键长变化越小,体系越稳定;随外加电场增强,长径比较大的纳米线体系态密度(DOS)和分波态密度(PDOS)均向低能方向移动,最高占据分子轨道(HOMO)-最低未占据分子轨道(LUMO)能隙减少,体系电荷移向NW顶端。DOS/PDOS,HOMO/LUMO,能隙及有效功函数分析结果表明,具有较小横截面积的NW-1场发射性能最佳。
The structural stability and field emission properties of zinc oxide nanowires (ZnONW) with different cross section have been investigated by first-principles method based on density functional theory. The results show that ZnONW with large diameter is more stable, and decreases the variation of the length of Zn-O bond after atomic relaxation. The density of states (DOS) and partial densities of states (PDOS) of NW with large aspect ratio shifts towards the low energy position with the increase of the applied electric field, and the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap decreases drastically, and the electrons congregate to the upside of ZnONW. The analysis of DOS/PDOS, HOMO/LUMO, and effective work function indicate that the NW- 1 with the smallest cross section is more propitious to the electron field emission than other systems.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2014年第1期173-179,共7页
Journal of Synthetic Crystals
基金
陕西省自然科学基础研究计划重点项目(2011J2009)
关键词
第一性原理
ZNO纳米线
场发射
电子结构
first-principle
ZnO Nanowire
field emission
electronic structure
作者简介
王欣(1988-),男,陕西省人,硕士。E—mail:765196442@qq.com
通讯作者:王发展,教授。E-mail:wangfz10_1@163.com