基于密度泛函理论下O和Na掺杂单层h-BN的电子结构和光学性质的分析
Analysis of electronic structures and optical properties of O and Na doped monolayer h-BN based on density functional theory
周国建 1彭章娥 1刘琳 1罗剑平1
作者信息
- 1. 上海应用技术大学城市建设与安全工程学院,上海 201418
- 折叠
摘要
基于密度泛函理论的第一性原理方法研究了 O、Na单掺杂及O和Na共掺杂单层h-BN的形成能、电子结构和光学性质.结果表明:单掺杂体系中,O掺杂N位置、Na掺杂B位置时,掺杂形成能最低;共掺杂体系中,O和Na邻位掺杂,掺杂形成能最低.与单层h-BN相比,引入杂质原子后的体系禁带宽度均减小,其中O掺杂为n型掺杂,Na掺杂为p型掺杂,而O和Na共掺h-BN体系为直接带隙材料,有利于提高载流子的迁移率.在光学性质方面,Na掺杂h-BN体系与O和Na共掺h-BN的静介电常数均增大,在低能区介电虚部和光吸收峰均发生红移,其中Na掺杂体系红移最为显著,极化能力最强.因此Na单掺和O和Na共掺有望增强单层h-BN的光催化能力,可扩展其在催化材料、光电器件等领域的应用.
Abstract
The formation energies,electronic structures and optical properties of O and Na single doped and O-Na co-doped monolayer h-BN are studied by using the first-principles method based on density functional theory.The results show that the doping formation energy is the lowest when O is doped at N position and Na is doped at B position;In the co-doped system,O and Na are ortho-doped,and the doping formation energy is the lowest.Compared with monolayer h-BN,the band gap width of the system is reduced after introducing im-purity atoms,in which O doping is n-type doping,Na doping is p-type doping,and O-Na co-doped h-BN system is a direct band gap material,which is beneficial to improve carrier mobility.In terms of optical prop-erties,the static dielectric constants of Na doped h-BN system and O and Na co-doped h-BN increase,and the imaginary parts of dielectric constants and optical absorption peaks in the low energy region are red-shifted.Among them,the Na doped system has the most significant redshift and the strongest polarization ability.There-fore,Na monodoping and O and Na co-doping are expected to enhance the photocatalytic ability of monolayer h-BN and hence expand its application in photocatalysis materials,optoelectronic devices and other fields.
关键词
单层h-BN/第一性原理/掺杂/电子结构/光学性质Key words
Monolayer h-BN/First-principles/Doping/Electronic structure/Optical properties引用本文复制引用
基金项目
国家自然科学基金重点项目(12032016)
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据