卤化硅烯结构、电子和光学性质的第一性原理研究  

First-principles studies on the structural,electronic and optical properties of halogenated silicene

作　　者：郭鑫 GUO Xin(North University of China,School of Information and Communication Engineering,Taiyuan 030051,China)

机构地区：[1]中北大学信息与通信工程学院,太原030051

出　　处：《原子与分子物理学报》2023年第4期97-103,共7页Journal of Atomic and Molecular Physics

基　　金：山西省基础研究计划(20210302124198,20210302124558);毁伤技术重点实验室开放研究基金(DXMBJJ2021-05);山西省高等学校科技创新计划(2020L0268,2020L0307);中北大学科学研究基金(XJJ201915)。

摘　　要：二维硅烯的商业用途通常受到其零带隙的抑制,限制了其在纳米电子和光电器件中的应用.利用基于密度泛函理论的第一性原理计算,单层硅烯的带隙通过卤原子的化学官能化被成功打开了,并综合分析了卤化对单层硅烯的结构,电子和光学性质的影响.研究结果表明卤化使结构变得扭曲,但保持了良好的稳定性.通过HSE06泛函,全功能化赋予硅烯1.390至2.123 eV的直接带隙.键合机理分析表明,卤原子与主体硅原子之间的键合主要是离子键.最后,光学性质计算表明,I-Si-I单层在光子频率为10.9 eV时达到最大光吸收,吸收值为122000 cm^(-1),使其成为设计新型纳米电子和光电器件的有希望的候选材料.Commercial purposes of two-dimensional silicene are usually suppressed by its zero band gap,which limits its application in nanoelectronic and optoelectronic devices.Here,using first-principles calculations based on density functional theory,we successfully opened the band gap of silicene monolayer by chemical functionalization with halogen atoms and comprehensively analyzed the effect of halogenation on the structural,electronic and optical properties of silicene monolayer.Our results demonstrate that halogenation gives a more distorted structure but maintains goodstability.Full-functionalization endows silicene a direct bandgap ranging from 1.390 to 2.123 eV by the HSE06 functional.The analysis of the bonding mechanism shows that the bonding between the halogen atom and the host silicon atom is predominantly ionic.Finally,optical property calculations show that the I-Si-I monolayer reaches a maximum optical absorption at a photon frequency of 10.9 eV with a value of 122000 cm^(-1),making them promising candidates for designing novel nanoelectronic and optoelectronic devices.

关 键 词：第一性原理 硅烯 化学功能化 结构性质 电子性质 光学性质 

分 类 号：O64[理学—物理化学]