Y,Zr,Nb掺杂对单层MoS_2电子结构的影响

Electronic Structure of Monolayer MoS_2 with Yttrium,Zirconium and Niobium Doping

本文基于第一性原理的方法研究了Y、Zr、Nb在Mo位掺杂单层MoS_2的能带结构和态密度。研究发现:Y、Zr、Nb三种杂质在Mo位掺杂使杂质原子附近的键长发生畸变,畸变最大的是Y掺杂体系;Y、Zr、Nb的掺杂改变了单层MoS_2能能带结构,使掺杂体系向导体转变;对于Y、Zr、Nb共掺杂体系,Y、Zr共掺杂增强了单层MoS_2导电性能;Y、Nb共掺杂单层MoS_2的费米能级穿过杂质能级,此处的能级处于半满状态,容易成为电子的俘获中心;Zr、Nb共掺杂体系的禁带中出现了多条杂质能级,同时导带能量上移;Y、Zr、Nb共掺杂可以很大程度改变单层MoS_2材料的电子结构。

Band structure and density of states of yttrium,zirconium and niobium doped single-layer MoS2 are studied by first principles method. It is found that the bond length of impurity atoms is distorted by yttrium,zirconium and niobium doped monolayer MoS2 in the Molybdenum position,but the distortion rate of yttrium doped system is the largest. Through the study of yttrium,zirconium and niobium co-doped system,that we can get the conductive property of monolayer MoS2 was improved by yttrium,zirconium codoping; the yttrium and niobium co-doped sites are easy to be the electron trapping centers the reason for the Fermi energy passes through the impurity levels and the energy level is half full. There are many impurity levels in the band gap in zirconium and niobium co-doped system,as well as conduction band energy move to high energy region. Electronic structure of monolayer MoS2 were changed in the co-doped systems.