碱土金属吸附二维α1硼烯结构和性质研究  

Investigation of structures and properties of two-dimensionalα1 borophene adsorbed with alkaline earth metal atoms and clusters

作　　者：韩健伟 边伟樾 刘锦 徐豪[1] 张孟 王潇 罗有华[1] HAN Jian-Wei;BIAN Wei-Yue;LIU Jin;XU Hao;ZHANG Meng;WANG Xiao;LUO You-Hua(East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学,上海200237

出　　处：《原子与分子物理学报》2020年第4期557-565,共9页Journal of Atomic and Molecular Physics

基　　金：基本科研业务费专项基金(222201714018,222201714050);大学生创新创业训练计划(国家级201810251078);华东理工大学第十七届USRP项目。

摘　　要：采用密度泛函理论系统计算和研究了碱土金属(铍、镁和钙)单原子、二聚体、双原子吸附新型二维α1硼烯后众多可能的吸附点和吸附情况.通过体系总能量的计算,鉴定了不同吸附体系最稳定的几何构型,并对其稳定性进行了详细地分析和讨论.经研究发现单原子铍和镁最低吸附点是空心位,而钙是顶位附近.通过吸附能计算发现二聚体碱土金属吸附硼烯后体系的稳定性高于单原子情况,但低于双原子吸附,表明碱土金属原子倾向于孤立地吸附于各自最低能量吸附点,而不是以团簇形式吸附.通过电荷转移和态密度进一步分析和讨论了碱土金属原子与硼烯的相互作用和成键方式,发现碱土金属与硼烯之间同时具有离子键和共价键性质.Many possible adsorption points and conditions of new two-dimensionalα1 borophene adsorbed with alkaline earth metal atoms(Be,Mg and Ca),dimers and diatomics have been systematically investigated by using density functional theory.The most stable adsorption geometries of different systems are identified and the stabilities are analyzed and discussed in detail by calculating the total energies.It has been found that the most stable adsorption sites of the Be and Mg atoms are right above the middle hollow site of borophene,while Ca atom prefers to adsorb near the top site of B atom.The adsorption energies show that the stability of the borophene adsorbed with alkaline earth metal dimer is higher than that of single atom,but lower than the case of diatomic adsorption.Which indicates that alkaline earth metal atoms tend to be individually adsorbed at their respective favoured adsorption sites instead of adsorption in the form of dimers.The interaction and bonding mode of alkaline earth metal atoms with borophene are further analyzed and discussed by charge transfer and density of states.It is found that alkaline earth metal atoms and borophene have a mixture of covalent and ionic characteristics.

关 键 词：第一性原理 硼烯 表面吸附 碱土金属 

分 类 号：O485[理学—固体物理]