Layered Hg3AsE4X as photo catalyst for water splitting under visible light

2018 4th International Conference on Environmental Science and Material Application

生态环境科学;材料科学

Liu, Jian^1

School of Materials Science and Engineering, Baise University, Guangxi

533000, China^1

关键词: DFT calculation;    Direct band gap semiconductors;    High efficient;    Over potential;    Visible light;    Visible light absorption;    Visible light region;    Water splitting;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/252/4/042041/pdf
DOI  :  10.1088/1755-1315/252/4/042041

来源: IOP

【 摘 要 】

A systematically study of layered Hg3AsE4X (E=S, Se; X=Cl, Br, I) is presented by density functional theory calculations. The family of layered Hg3AsE4X shows two types of electronic properties and exhibits a range of bandgaps from 2.22 to 2.53 eV. The calculated band edges of Hg3AsE4X further reveal that ten members of single layer MNX have both suitable band gaps and sufficient over-potentials for thermodynamically feasible water splitting. More fascinatingly, Hg3AsSe4X(X=Br, I) are direct band gap semiconductors with relative small band gaps (2.22-2.28eV), and the calculated optical absorption further convinces that such materials own outstanding properties for visible light absorption. Furthermore, by doping Se, the band gaps of Hg3AsS4X(X=Cl, Br) are further narrowed and significant improvements of optical absorption in visible light region are revealed by DFT calculation. Such results demonstrate that the single layered Hg3AsE4X (E=S, Se; X=Cl, Br, I) own high stability, versatile electronic properties, and high optical absorption, thus such materials have great chances to be high efficient photo catalysts for water-splitting.