单层MoS_2表面吸附Ag_6团簇电子结构的第一性原理计算

本文运用第一性原理研究了单层MoS_2在S位吸附Ag_6团簇的稳定性、能带结构和态密度.结果表明,Ag_6团簇在S位单点位吸附的稳定性强于双点位吸附、三点位吸附;其中吸附体系禁带中产生了2条杂质能级,原因在于Ag原子与S形成共价键下的施主能级与受主能级;Ag_6团簇在单层MoS_2的吸附导致态密度峰值在费米能级处发生劈裂,说明Ag_6团簇的吸附会增强单层MoS_2的光电特性;单层MoS_2的能带结构可以通过表面吸附Ag_6团簇以及金属团簇进行调控;在实际的生产应用中依据不同的金属团簇吸附于单层MoS_2表面得到需要的的半导体器件.

First principles study on electronic properties of monolayer MoS2 with Ag6 cluster adsorbing

In this paper, band structure, density of states and stability of monolayer MoS2 adsorbed Ag6 clusters are studied by first principles method. It is found that the stability of single site adsorption is stronger than that of double point adsorption and three point adsorption in the monolayer MoS2 adsorbed Ag6 cluster system. All the adsorption systems increase 2 impurity levels in the band gap because of the donor and acceptor levels are formed by covalent bonds between the Ag and the S atom. The peak of the density of states splits at the Fermi level in the adsorption systems, which indicates that the adsorption of Ag6 clusters will enhance the photoelectric properties in monolayer MoS2. Meanwhile, the band structure of monolayer MoS2 can be controlled by surface adsorption of Ag6 clusters or metal clusters. In practical applications, we can absorb suitable metal clusters for a wide variety of semiconductor devices in monolayer MoS2.