IB族金属掺杂单层MoS_2电子结构的研究

Study on the Electronic Structure of IB Metal Doped Monolayer MoS_2

本文基于密度泛函理论框架下的第一性原理,采用数值基组研究了IB族金属Cu,Ag,Au掺杂单层MoS_2的键长畸变、稳定性、能带结构和态密度。探讨了Cu,Ag,Au掺杂对单层MoS_2电子结构的影响;结果表明:Cu,Ag,Au在Mo位掺杂都会导致杂质原子附近的键长发生畸变,但畸变程度略有差异,Cu掺杂体系的稳定性强于Ag,Au在Mo位掺杂的体系;Cu,Ag,Au掺杂致使单层MoS_2的禁带中出现新能级;Cu,Ag,Au在S位吸附的稳定性强于Mo位吸附,对于MoS_2在S位吸附Cu,Ag,Au对其禁带的宽度影响较小;但稳定性最强的都是Au元素的吸附体系。

To study the effect of IB metal element doping on the electronic structure of monolayer MoS2,the bond length distortion,stability,band structures,and density of states of Cu,Ag and Au doped and intrinsic monolayer MoS2 are calculated,respectively,using first-principles density functional theory based on the numeric basis sets method.Calculations indicate that the bond length in the vicinity of the impurity atom is distorted,because of the impurity atoms are introduced.In the Cu,Au,Ag doped systems,the most stable structure is Cu-doped monolayer MoS2,meanwhile,there are new impurity levels in the band gap,which indicates that the doping of IB metal will affect the photoelectric properties of the monolayer MoS2.The IB metal adsorbed in the S position s stability is stronger than that of Mo,and adsorption has little influence on the band gap,but stability is the strongest effect of Au system in the monolayer MoS2 system.