过渡金属掺杂对二维TiSi_(2)N_(4)的电子结构及光学性质影响  

Effect of transition metal doping on the electronic structure andoptical properties of two-dimensional TiSi_(2)N_(4)

作　　者：李雷 王一[1,2] 王广 张正丽 丁召[1,2] LI Lei;WANG Yi;WANG Guang;ZHANG Zhengli;DING Zhao(School of Big Data and Information Engineering,Guizhou University,Guiyang 550025,China;Semiconductor Power Device Reliability Engineering Research Center,Ministry of Education,Guiyang 550025,China)

机构地区：[1]贵州大学大数据与信息工程学院,贵阳550025 [2]教育部半导体功率器件可靠性工程研究中心,贵阳550025

出　　处：《功能材料》2024年第11期11024-11030,共7页Journal of Functional Materials

基　　金：国家自然科学基金项目(12164009,12304259);贵州省自然科学基金项目(QKHZK[2023]057);贵州省高等学校青年人才成长计划项目(Grant No.QJHKY-[2022]141);贵州大学人才引进项目(GDRJH-[2021]86)。

摘　　要：基于密度泛函理论(DFT)的第一性原理研究Co、Fe、Ni替位掺杂2D TiSi_(2)N_(4)后的晶体结构、电学性质以及光学性质。本征2D TiSi_(2)N_(4)的带隙为2.799 eV,为间接带隙半导体,且通过3种金属掺杂后变为直接带隙半导体;自旋向下的能带主要贡献来自于N-p轨道,Co、Ni掺杂后的2D TiSi_(2)N_(4)在禁带中分别引入2条和4条施主杂质能级,使得禁带宽度变窄,增加载流子浓度,但并不影响2D TiSi_(2)N_(4)的导电性;通过Co、Fe、Ni掺杂后的TiSi_(2)N_(4)在可见光和部分紫外光波段吸收能力得到显著增强,对紫外光的反射能力有所减弱;另外,通过对Fe、Ni掺杂2D TiSi_(2)N_(4)的SLME效率的计算,发现二者均可作为1μm厚度的太阳能电池中吸收层的可选材料。In this paper,the crystal structure,electrical properties,and optical properties of Co,Fe,and Ni substitutively doped 2D TiSi_(2)N_(4) are investigated based on the first principles of density-functional theory(DFT).The band gap of intrinsic 2D TiSi_(2)N_(4) is 2.799 eV,which is an indirect band gap semiconductor and becomes a direct band gap semiconductor after doping with three metals,and the main contribution to the spin-down energy band comes from the N-p orbitals,and the Co-and Ni-doped 2D TiSi_(2)N_(4) introduces 2 and 4 siderophore impurity energy levels into the forbidden band,which narrows the width of the forbidden band and increases the carrier concentration,respectively,but does not affect the electrical conductivity of 2D TiSi_(2)N_(4),and the TiSi_(2)N_(4) doped with Co,Fe,and Ni has significantly enhanced absorption in the visible and partially UV bands,and the reflection of UV light has been reduced.In addition,through the calculation of the SLME efficiency of Fe-and Ni-doped 2D TiSi_(2)N_(4),it is found that they can be used as an optional material for the absorber layer in a solar cell with a thickness of 1μm.

关 键 词：密度泛函理论 2D TiSi_(2)N_(4) 掺杂 电学性质 光学性质 

分 类 号：TN304[电子电信—物理电子学]