基于第一性原理的二维材料黑磷砷气体传感器的机理研究  

First principle study on gas sensor mechanism of black-AsP monolayer

作　　者：徐强 段康 谢浩 张秦蓉 梁本权 彭祯凯 李卫 Xu Qiang;Duan Kang;Xie Hao;Zhang Qin-Rong;Liang Ben-Quan;Peng Zhen-Kai;Li Wei(Jiangsu Provincial Optical Communication Engineering Technology Research Center,College of Electronic and Optical Engineering and College of Microelectronics,Nanjing Universuty of Posts and Telecommunications,Nanjing 210023,China;State Key Laboratory of Luminescent Materials and Devices,South China University of Technology,Guangzhou 510641,China;State Key Laboratory of Millimeter Waves,Southeast University,Nanjing 210096,China;National Laboratory of Solid State Microstructures,School of Physics,Nanjing University,Nanjing 210093,China)

机构地区：[1]南京邮电大学电子与光学工程学院、微电子学院,江苏省光通信工程技术研究中心,南京210023 [2]华南理工大学,发光材料与器件国家重点实验室,广州510641 [3]东南大学,毫米波国家重点实验室,南京210096 [4]南京大学物理学院,固体微结构物理国家重点实验室,南京210093

出　　处：《物理学报》2021年第15期241-248,共8页Acta Physica Sinica

基　　金：中国博士后科学基金(批准号:2018T110480);江苏省高等学校自然科学基金(批准号:20KJA510001);华南理工大学发光材料与器件国家重点实验室开放基金(批准号:2020-skllmd-03);东南大学毫米波国家重点实验室开放基金(批准号:K202003);南京大学固体微结构物理国家重点实验室开放基金(批准号:M32001);江苏省光通信工程技术研究中心开放基金(批准号:ZXF201904)资助的课题.

摘　　要：通过密度泛函理论计算,研究了气体小分子吸附在单层黑磷砷表面的电学和磁学特性.选择4个初始吸附点位来探索CO,CO_(2),NH3,SO_(2),NO和NO_(2)气体分子最优的吸附位置,计算了吸附能、吸附距离和电荷转移等电子结构参数,确定了吸附类型和敏感气体.结果表明,单层黑磷砷以强的物理吸附对NO_(2)和SO_(2)气体敏感,而通过化学吸附对NO气体敏感并且N原子和P原子间还形成新的化学键.从能带结构角度,CO,CO_(2)和NH3这三种气体吸附对黑磷砷的能带结构影响很小,SO_(2)气体吸附增大带隙宽度.磁性气体NO和NO_(2)的吸附则在费米能级附近引入杂质能带,这主要来源于N原子和O原子的p轨道,并且减小了带隙宽度.NO和NO_(2)气体还分别诱导了0.83μB和0.78μB的磁矩,使得整个体系带有磁性.理论研究表明,单层黑磷砷是检测NO,NO_(2)和SO_(2)气体的良好气敏材料.Since the successful synthesis of graphene,two-dimensional materials,including hexagonal boron nitride and transition mental dichalcogenides,have attracted wide attention due to their extraordinary properties and extensive applications.Recent researches have revealed that the sensing system based on graphene or MoS2 can efficiently sense various gas molecules.However,the utility of these materials is limited by their inherent weakness,i.e.the zero bandgap in graphene and the relatively low mobility in MoS2,which impede their applications in electronic devices.This further stimulates the motivation of researchers to find more novel 2D materials.Black arsenic phosphide(AsP)monolayer,a novel two-dimensional nanomaterial with the characteristics of model direct bandgap and superhigh carrier mobility,is an ideal material for gas sensor.Here in this work,we investigate the electronic and magnetic properties of monolayer AsP absorbed with small gas molecules by using first-principle calculations based on density functional theory.Four initial absorption sites are selected to explore the optimal absorption positions of CO,CO_(2),NH3,SO_(2),NO and NO_(2) absorbed on the monolayer AsP.The purpose is to calculate the optimal absorption configurations,the absorption energy,absorption distance,and charge transfer,thereby investigating the absorption types.The results revel that the monolayer AsP is sensitive to NO_(2) gas and SO_(2) gas via strong physical absorption,and NO gas by chemical absorption,forming a new bond between N atom and O atom.The CO,CO_(2) and NH3 gas are absorbed on AsP monolayer with weak van Waals force.From the point of view of charge transfer,the CO,CO_(2),and NH3 molecules are one order of magnitude smaller than SO_(2),NO and NO_(2),approximately 0.03e and the charge transfer of NO gas is 0.21e,highest in all gases.Besides,the effects of absorption on the electrons of AsP are investigated.The results show that the absorption of CO,CO_(2) and NH3 molecules have little effect on band structure,and that

关 键 词：黑磷砷 第一性原理 气体传感器 

分 类 号：TB34[一般工业技术—材料科学与工程] TP212[自动化与计算机技术—检测技术与自动化装置]