新型二维铜族硫族化合物MX(M=Cu,Ag,Au;X=S,Se,Te):二维极化金属与可见光催化剂  

Emerging group-11 monochalcogenide MX(M=Cu,Ag,Au;X=S,Se,Te)monolayers:Two-dimensional polarized metals and visible-light-driven photocatalysts

作　　者：薛宇飞 高蕾 叶宇娇 何世豪 蒋丽 田元 任伟娜 晒旭霞 卫婷婷 曾春华 王华 Yufei Xue;Lei Gao;Yujiao Ye;Shihao He;Li Jiang;Yuan Tian;Weina Ren;Xuxia Shai;Tingting Wei;Chunhua Zeng;Hua Wang(Institute of Physical and Engineering Science/Faculty of Science,Kunming University of Science and Technology,Kunming 650500,China;State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming University of Science and Technology,Kunming 650093,China)

机构地区：[1]Institute of Physical and Engineering Science/Faculty of Science,Kunming University of Science and Technology,Kunming 650500,China [2]State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming University of Science and Technology,Kunming 650093,China

出　　处：《Science China Materials》2023年第9期3601-3608,共8页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (12265017 and 12247205);Yunnan Fundamental Research Projects (202201BE070001-009, 202101AU070043, 202201AV070003 and 202101AS070018);Yunnan Province Computational Physics and Applied Science, Technology Innovation Team;Yunnan Ten Thousand Talents Plan Young & Elite Talents Project。

摘　　要：二维过渡金属硫族化合物因其优异的特性和广泛的应用前景而受到众多研究领域的关注.本文报道了一类具有极化金属和可见光催化特性的新型二维铜族硫族化合物MX (M=Cu,Ag,Au;X=S,Se,Te).金属性ι-CuS、ι-AgS和ι-AgTe的原子结构是面外反演非对称的,其底部和顶部具有不同功函数.因而这些金属单层与石墨烯形成异质结可使其功函数从4.35 eV扩展到3.87–5.04 eV.半导体性β-AgSe和α-AuTe/α-AuS/α-AuSe在pH=0/7下仅仅满足H+/H_(2)和H_(2)O/O_(2)反应的带边要求.进一步,α-AuSe/α-AuTe异质结作为Z型光催化剂在可见光驱动的水分解中具有极大的应用潜力,其具有合适的带边位置、增强的光吸收以及高太阳能-氢能转换效率(20.47%).这些优异的性能使二维铜族硫族化合物MX成为二维过渡金属硫族化合物研究领域的重要组成部分,有望得到理论和实验的密切关注.Two-dimensional(2D)transition metal chalcogenides have garnered significant research interest owing to their novel properties and potential applications.In this paper,we report a novel class of group-11 chalcogenide MX(M=Cu,Ag,Au;X=S,Se,Te)monolayers based on first-principles calculations,which demonstrate significant application potential as polarized metals and visible-light-driven photocatalysts.ι-CuS,ι-AgSι-AgTe,η-CuSe,andη-CuTe were found to be metals,whileβ-AgSe,α-AuS,α-AuSe,andα-AuTe were observed to be semiconductors with a bandgap of 1.46,2.14,1.77,and 1.37 eV respectively.Interestingly,the work functions of the bottom and top sides ofι-CuS,ι-AgS,andι-AgTe differed owing to the out-of-plane inversion asymmetry of theιphase.Moreover,these metallic MX monolayers were used to form graphene-based metal-metal heterostructures;accordingly,the work function of graphene could be modulated from 4.35 eV to the range of 3.87–5.04 eV.For semiconducting MX monolayers,α-phase andβ-phase monolayers just satisfied the band edge requirement for the H+/H_(2) and H_(2)O/O_(2) reaction at pH 0/7,respectively.Further investigations on theα-AuSe/α-AuTe heterostructure demonstrated its great application potential as a Z-scheme photocatalyst in visible-light-driven overall water splitting with appropriate band alignment,enhanced optical absorbance and high solar-to-hydrogen energy conversion efficiency(20.47%).Benefitting from these excellent properties,2D group-11 chalcogenide MX monolayers can be potentially used as polarized metals and visible-lightdriven water splitting photocatalysts.

关 键 词：过渡金属硫族化合物 功函数 金属性 MX 半导体性 原子结构 转换效率 水分解 

分 类 号：O643.36[理学—物理化学] O644.1[理学—化学]