二维As_(2)O_(3)光催化性质理论研究  

Theoretical study on the photocatalytic properties of two-dimensional As_(2)O_(3)

作　　者：王晓雯 左雅敏 王燕 WANG Xiaowen;ZUO Yamin;WANG Yan(School of Basic Medicine, Hubei University of Medicine, Shiyan, Hubei 442000, China)

机构地区：[1]湖北医药学院基础医学院,湖北十堰442000

出　　处：《华中师范大学学报（自然科学版）》2021年第6期1037-1043,1064,共8页Journal of Central China Normal University：Natural Sciences

基　　金：十堰市指导性科研项目(19Y06).

摘　　要：基于密度泛函理论的超软赝势第一性原理计算方法,该文提出了一种新型P-3m1相二维As_(2)O_(3),并研究其结构稳定性,电子结构和光催化性质.计算结果显示,二维As_(2)O_(3)具备较好的稳定性,并具有1.04 eV的间接能隙.基于形变势理论进一步计算了As_(2)O_(3)的载流子迁移率,发现其电子和空穴的迁移率表现出明显的各向异性,沿armchair和zigzag方向的电子/空穴迁移率分别为1259.91/115.41 cm^(2)·V^(-1)·s^(-1)和1254.21/36.12 cm^(2)·V^(-1)·s^(-1),这说明As_(2)O_(3)具备很低的电子-空穴复合率,拥有较高的光催化活性.对比标准氢电极的氧化还原势发现,二维As_(2)O_(3)具备2.57 eV的氧化势能,能够光催化水裂解出O_(3),O_(2)和H_(2)O_(2)等.此外,二维As_(2)O_(3)对可见光和紫外光表现出强烈的吸收效果,吸收系数高达10^(5) cm^(-1).这表明二维As_(2)O_(3)在纳米电子器件和光催化领域有着潜在的应用前景.Based on the first-principles calculation method of ultra-soft pseudopotential density functional theory,a novel two-dimensional As_(2)O_(3) of P-3m1 phase is proposed,its stability,electronic structures and photocatalytic properties are further studied.The results show that As_(2)O_(3) is indirect bandgap semiconductor with band-gap of 1.04 eV,and show high stability.Based on the deformation potential theory,we calculated the carrier mobility of monolayer As_(2)O_(3),the results show that the mobility of electrons and holes are obviously anisotropic.The electron/hole mobility along Armchair/Zigzag directions are 1259.91/115.41 cm^(2) V^(-1)·s^(-1) and 1254.21/36.12 cm^(2) V^(-1)·s^(-1),respectively,indicating that monolayer As_(2)O_(3) has a very low electron-hole recombination rate and with high photocatalytic activity.Compared with the REDOX potential of the standard hydrogen electrode,it is found that the oxidation potential of monolayer As_(2)O_(3) is 2.57 eV,which can photocatalyze water cracking to produce O_(3),O_(2) and H_(2)O_(2) et al.Furthermore,monolayer As_(2)O_(3) shows strong absorption effect to visible and ultraviolet light,and the absorption coefficient is up to 10^(5) cm^(-1).These properties indicate that monolayer As_(2)O_(3) has a potential application prospect in nano electronic devices and photocatalysis.

关 键 词：二维As_(2)O_(3) 载流子迁移率 光催化 光学性质 

分 类 号：O482[理学—固体物理]