Sb/SnC范德瓦耳斯异质结光电性质的层间转角依赖性及其应用  

Interlayer angle dependence of photoelectric properties of Sb/SnC van der Waals heterojunction and its application

作　　者：汪帆帆 陈栋[1] 袁军[1] 张珠峰[1] 姜涛[1] 周骏[1] Wang Fan-Fan;Chen Dong;Yuan Jun;Zhang Zhu-Feng;Jiang Tao;Zhou Jun(School of Physical Science and Technology,Ningbo University,Ningbo 315211,China)

机构地区：[1]宁波大学物理科学与技术学院,宁波315211

出　　处：《物理学报》2024年第22期238-247,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:62375146,61675104,61320106014);宁波大学王宽诚幸福基金资助的课题.

摘　　要：基于二维锡基材料与锑烯单层构建了具有不同层间转角的6种Sb/SnC二维范德瓦耳斯异质结,并根据第一性原理对其光电性质及应用开展研究.研究结果表明,6种层间转角的Sb/SnC异质结具有不同的带隙,且当层间转角为10.89°,19.11°,23.41°和30°时,Sb/SnC异质结显示出Ⅰ型能带结构,而当层间转角为8.95°和13.59°时,则是Ⅱ型能带结构.同时,6种异质结的轨道投影带结构表明,由于层间转角改变了异质结的原子堆叠方式,从而改变了轨道耦合并进一步调控了异质结的电子结构.此外,吸收谱的计算表明,与Sb和SnC单层相比,异质结的光吸收系数在可见光区域得到显著增强,且对应不同的层间转角,异质结的光吸收特性差异明显.在应用方面,作为太阳能电池材料,层间转角为8.95°和13.59°的Sb/SnC异质结分别具有17.48%和18.59%的光电转化效率;作为全解水光催化剂,层间转角为8.95°的异质结可对pH值为0-2的水完全催化分解,而层间转角为13.59°的异质结仅可以对pH值为0-1的水进行催化分解.因此,作为一个重要的结构参数,层间转角可以有效地调控Sb/SnC异质结的光电特性,具有特定转角的Sb/SnC异质结可在太阳能和光催化领域获得应用.The discovery of novel properties in twisted bilayer graphene has opened up new avenues of research in physics and materials science,making the twistronics a new research hotspot.In this paper,based on twodimensional tin-based materials and antimonene monolayers,six types of Sb/SnC two-dimensional van der Waals heterostructures(vdWH)with different interlayer twist angles are constructed,and their optoelectronic properties and applications are studied by first-principles calculations.All modeling and calculations are performed using the density functional theory(DFT)software Quantum-ATK.The results show that the Sb/SnC vdWHs with six different interlayer twist angles have various band gaps,and when the interlayer twist angles are 10.89°,19.11°,23.41°,and 30°,the Sb/SnC vdWH exhibit a type-I band edge alignment,while at 8.95°and 13.59°,they present a type-II band structure.The results of the orbital-projected band structures of the Sb/SnC vdWHs reveal that the variation in interlayer twist angles changes the atomic stacking in the heterostructures,thereby modifying orbital coupling and further tuning the electronic structure of the heterostructures.Additionally,the calculated absorption spectra indicate that comparing individual Sb and SnC monolayers with Sb/SnC vdWHs,the latter’s absorption coefficient r is significantly enhanced in the visible light region,and the optical absorption characteristics of the heterostructures with different interlayer twist angles vary markedly.In terms of applications,as materials for solar cells,the Sb/SnC vdWHs with interlayer twist angles of 8.95°and 13.59°exhibit photovoltaic conversion efficiencies of 17.48%and 18.59%,respectively;as photocatalysts for the complete water splitting,the Sb/SnC vdWH with an interlayer twist angle of 8.95°can catalytically decompose water across a pH range of 0-2,while a twist angle of 13.59°confines its catalytic activity to a pH value between 0 and 1.Therefore,Sb/SnC van der Waals heterostructures have special rotation angles and have

关 键 词：范德瓦耳斯异质结 第一性原理 光电特性 层间转角 

分 类 号：O469[理学—凝聚态物理] TB34[理学—电子物理学]