石墨烯吸附Al_(2)Cl_(6)分子的第一性原理与Monte Carlo研究  

First-principles and Monte Carlo studies on adsorption of Al_(2)Cl_(6) molecule on graphene

作　　者：苗中正 MIAO Zhong-Zheng(School of Physics and Electronic Engineering,Yancheng Teachers University,Yancheng 224007,China)

机构地区：[1]盐城师范学院物理与电子工程学院,盐城224000

出　　处：《原子与分子物理学报》2022年第5期97-104,共8页Journal of Atomic and Molecular Physics

基　　金：江苏省自然科学基金青年项目(BK20201064);江苏省高等学校自然科学研究面上项目(19KJB430040);盐城师范学院科研启动金(72051671002C)。

摘　　要：采用第一性原理与蒙特卡罗方法研究Al_(2)Cl_(6)气体分子在石墨烯表面的吸附性能与光电性质,结果表明:(1)石墨烯对Al_(2)Cl_(6)气体分子具有较强的物理吸附作用,两个Al原子的连线与石墨烯平面近乎平行且两个Al原子处于紧靠顶位的桥位位置时最稳定;(2)温度升高不利于Al_(2)Cl_(6)气体分子吸附并存在阶跃式降低,气体逸度增加有利于吸附并存在阶跃式升高,Al_(2)Cl_(6)气体分子插入石墨/双层石墨烯/多层石墨烯宜将温度维持在AlCl_(3)沸点附近,并增加气体的压力;(3)Al_(2)Cl_(6)的吸附对石墨烯的电子结构进行了调控,但没有明显改变石墨烯费米能级附近的态密度以及“赝能隙”;(4)Al_(2)Cl_(6)的吸附对体系光学参数的影响十分明显,静态介电常数提高近5倍,使体系屏蔽效应有较大增强,在长波波段的吸收性能、反射性能及光电导也有了明显提升.First-principles calculations and Monte Carlo methods were carried out to study the adsorption performance and photoelectric properties of Al_(2)Cl_(6)gas molecules on the surface of graphene.The results reveal that:(1)Graphene has a strong physical adsorption effect on Al_(2)Cl_(6)gas molecules.When the connection line of the two Al atoms is parallel to the graphene plane and the two Al atoms in the bridge position close to the top position,the adsorption structure has the most stable configuration.(2)The increase in temperature is not conducive to the adsorption of Al_(2)Cl_(6)gas molecules and there is a step decrease.The increase of gas fugacity is conducive to the adsorption and there is a step increase.The temperature should be maintained near the boiling point of AlCl_(3) and the pressure of the gas be increased when Al_(2)Cl_(6)gas molecules are inserted into graphite/double-layer graphene/multilayer graphene.(3)The adsorption of Al_(2)Cl_(6)regulates the electronic structure of graphene,but does not significantly change the density of states and the"pseudo-energy gap"near the Fermi level of graphene.(4)The adsorption of Al_(2)Cl_(6)has a very obvious influence on the optical parameters of the system.The static dielectric constant is increased by nearly 5 times,which greatly enhances the shielding effect of the system,and the absorption performance,reflection performance and photoconductivity in the long wave band have also been significantly improved.

关 键 词：AlCl_(3)-石墨/石墨烯插层化合物 金属氯化物 吸附 密度泛函理论 蒙特卡罗 光电性能 

分 类 号：O552[理学—热学与物质分子运动论]