原子吸附对二维GeSe光电性质的影响  

Effect of atomic adsorption on the photoelectric properties of two-dimensional GeSe

作　　者：张国英[1] 于乐 管永翔 ZHANG Guoying;YU Le;GUAN Yongxiang(College of Physical Science and Technology,Shenyang Normal University,Shenyang 110034,China)

机构地区：[1]沈阳师范大学物理科学与技术学院,沈阳110034

出　　处：《沈阳师范大学学报（自然科学版）》2022年第3期193-201,共9页Journal of Shenyang Normal University:Natural Science Edition

基　　金：国家自然科学基金资助项目(51371049)。

摘　　要：GeSe作为一种Ⅳ-Ⅵ族半导体,具有优良的光电性质。二维GeSe具有直接带隙,带隙值在1.0~1.2 eV,与Si的带隙接近,因而单层GeSe可以用于光电领域。应用基于密度泛函理论的第一性原理方法探究了Al,O,B吸附对二维GeSe材料光电性质的影响,计算结果表明采用广义梯度近似(PW91形式下)交换关联泛函能够更好地描述GeSe单层的电子性质。吸附能计算结果表明,O,Al,B原子能稳定吸附在GeSe单层上,其中O形成的吸附最稳定。能带和态密度分析表明,吸附B,Al原子在带隙中产生的杂质能带使GeSe单层导电类型发生了改变,吸附原子调制了GeSe单层的带隙的宽度和光吸收的吸收边。光学性质计算结果表明,吸附原子影响了GeSe单层的折射率、消光性质,同时调控了光吸收和反射性质。Al吸附增强了从红外到可见光再到紫外光区整个光谱区的吸收;B吸附增强了从可见光到紫外光区的光吸收。同时,B,Al吸附也会增强光的反射,尤其是紫外光区的反射。总之,该研究为GeSe二维材料在光电领域的应用提供了可靠的理论依据。GeSe,as aⅣ-Ⅵgroup semiconductor,has excellent optoelectronic properties.Two-dimensional GeSe has a direct band gap with a gap value in the range of 1.0~1.2 eV,which is close to the band gap of Si,so single-layer GeSe can be used in the optoelectronic field.In this paper,the effect of Al,O and B adsorption on the photoelectric properties of two-dimensional GeSe material is investigated by using the first-principles method based on density functional theory.The calculation results show that the electronic properties of GeSe single-layer can be better described by using GGA(in the form of PW91)exchange-correlation functional.The calculation results of adsorption energy show that O,Al and B atoms are stably adsorbed on GeSe monolayer,and the adsorption of O on GeSe monolayer is the most stable.The analysis of band structure and density of states shows that the impurity band generated by the absorbed B,Al atom in the band gap can change the conduction type of GeSe monolayer.The absorbed atom modulate the band gap and the optical absorption edge of GeSe monolayer.The calculation results of optical properties show that the absorbed atoms affect the refractive index and extinction properties of GeSe monolayer,and regulate the optical absorption and reflection properties at the same time.Al adsorption enhances the absorption of GeSe monolayer across all spectrums,including UV,visible,and infrared;B increases the absorption of GeSe monolayer from the visible to UV region.Al,B adsorption increases the reflection of light,especially UV light.In conclusion,our study provides a reliable theoretical basis for the application of GeSe two-dimensional materials in the field of optoelectronics.

关 键 词：GeSe单层 密度泛函 光学性质 吸附 调控 

分 类 号：O482.31[理学—固体物理]