摘要
基于密度泛函理论,研究了二硫化钼/石墨烯(MoS_(2)/Gr)异质结及在异质结表面进行氢化后的结构稳定性、电子性能及光学性质;建立MoS_(2)/Gr异质结结构模型,计算了氢化后的异质结的能带结构、态密度及光吸收系数。研究发现:MoS_(2)/Gr异质结能带的带隙只有0.055 eV,无法用于电子器件;在异质结上表面或在异质结上下表面进行氢化,都可以改变异质结的能带。尤其是在异质结石墨烯的上表面添加8个氢原子后带隙变为1.076 eV;MoS_(2)/Gr异质结及其表面进行氢化后的光吸收峰均在220 nm左右的紫外光区,且在对异质结进行表面氢化后提高了对可见光的吸收率。总之,在MoS_(2)/Gr异质结表面进行氢化的方法可对MoS_(2)/Gr异质结的带隙进行调控,并且可以提高其对可见光的利用,这为石墨烯基二维材料的应用提供了新的途径。
Based on the density functional theory,the structural stability,electronic properties and optical properties of the molybdenum disulfide/graphene(MoS_(2)/graphene)heterojunction and hydrogenation on the surface of the heterojunction were studied.The MoS_(2)/graphene heterojunction structure model was established,and the band gap structure,density of states and light absorption coefficient of the hydrogenated heterojunction were calculated.The study found that the band gap of the MoS_(2)/graphene heterojunction is only 0.055 eV,which cannot be used in electronic devices.Hydrogenation on the upper surface of the MoS_(2)/graphene heterojunction or on the upper and lower surfaces of the heterojunction can change its band gap.It can be seen that hydrogenation can adjust the band gap of MoS_(2)/graphene heterojunction.In particular,the band gap becomes 1.076 eV after adding 8 hydrogen atoms to the upper surface of grapheneofthe heterojunction.The light absorption peaks of MoS_(2)/graphene heterojunction and after hydrogenation on the surface of MoS_(2)/graphene heterojunction are both in the ultraviolet region of about 220 nm,and the absorption of visible light is improved after surface hydrogenation of the heterojunction.In short,the method of hydrogenation on the surface of the MoS_(2)/graphene heterojunction can adjust the band gap of the MoS_(2)/graphene heterojunction,and can improve its utilization of visible light,which provides a new way for the application of graphene-based two-dimensional materials.
作者
张国英
张安国
孟春雪
ZHANG Guoying;ZHANG Anguo;MENG Chunxue(College of Physical Science and Technology, Shenyang Normal University, Shenyang 110034, China)
出处
《沈阳师范大学学报（自然科学版）》
CAS
2021年第3期199-204,共6页
Journal of Shenyang Normal University:Natural Science Edition
基金
国家自然科学基金资助项目(51371049)。
关键词
石墨烯
二硫化钼
异质结
氢化
第一性原理
graphene
mlybdenum disulfide
heterojunction
hydrogenation
first-principles calculation study
