扶手椅型C_(3)B纳米带:结构稳定性、电子特性及调控效应  

Structural stability,electronic properties,and physical modulation effects of armchair-edged C_(3)B nanoribbons

作　　者：曹胜果 韩佳凝 李占海 张振华[1] Cao Sheng-Guo;Han Jia-Ning;Li Zhan-Hai;Zhang Zhen-Hua(Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学,柔性电子材料基因工程湖南省重点实验室,长沙410114

出　　处：《物理学报》2023年第11期275-287,共13页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61771076);柔性电子材料基因工程湖南省重点实验室开放基金(批准号:202020);湖南省研究生创新项目(批准号:CX20210823)资助的课题.

摘　　要：单层C_(3)B是典型的类石墨烯二维材料,已在实验上成功制备.采用密度泛函理论方法(DFT)研究了扶手椅型单层C_(3)B纳米带的结构稳定性、电子性质及物理调控效应,计算结果表明:对于裸边纳米带,如果带边缘全由C原子组成(AA型),则电子相为半导体;两个带边缘均由C与B原子混合组成时(BB型),则纳米带的电子相为金属;而纳米带的一边由C原子组成、另一边由B与C原子混合构成(AB型),则纳米带的电子相为金属.这说明纳米带边缘的B原子对于纳米带成为金属或半导体起决定作用.而对于H端接的纳米带,它们全部为直接或间接带隙半导体.H端接的纳米带载流子迁移率一般比裸边纳米带低,这与它们较大的有效质量及较高的形变势有密切关系.同时发现半导体性质的纳米带对物理调控非常敏感,特别是在压应变和外电场作用下,纳米带的带隙明显变小,这有利于对光能的吸收和研发光学器件.C_(3)B monolayer is a typical graphene-like two-dimensional material,which has been successfully prepared experimentally.Here,we use the density functional theory to study the structural stability,electronic properties and physical regulation effects of its armchair-edged nanoribbons.The results show that for the bare-edged nanoribbons,if the ribbon edges are composed of C atoms completely(AA-type),their electronic phase is a semiconductor;when both ribbons edges consist of C and B atoms(BB-type)jointly,their electronic phase is a metal;if one edge of the ribbon is composed of C atoms and the other edge is comprised of B and C atoms(ABtype),their electronic phase is also a metal.This suggests that the B atom located at the ribbon edge plays an important role in determining whether nanoribbons is a metal or semiconductor.While for the H-terminated nanoribbons,they are all direct or indirect band-gap semiconductors.The carrier mobility of H-terminated nanoribbons is generally lower than that of bare-edged nanoribbon,which is closely related to their larger effective mass and higher deformation potential values.Meanwhile,it is found that the semiconducting nanoribbons are very sensitive to physical regulation,especially under applied compressive strain and external electric field,the band gap of the nanoribbons becomes very smaller,which is favorable for the absorption of light energy and development of novel optical devices.

关 键 词：C3B纳米带 结构稳定性 电子性质 载流子迁移率 物理调控 

分 类 号：TB383.1[一般工业技术—材料科学与工程]