新型二维GeC/InSe异质结光催化全解水性能的第一性原理研究

A First-Principles Study on Photocatalytic Performance of a Novel Two-Dimensional GeC/InSe Heterostructure for Overall Water Splitting

基于密度泛函理论方法,系统研究了新型二维GeC/InSe异质结的电子、光学性质和光催化特性。结果表明,二维GeC/InSe异质结的晶格失配率为0.98%,形成能为-0.135eV/atom,证明异质结的结构稳定。其次,异质结是带隙值为1.82eV的间接带隙半导体材料,表现为Ⅱ型能带对齐,价带和导带的带偏置分别为1.65eV和0.90eV,能够有效降低电子和空穴的复合率,提高GeC/InSe异质结的光催化性能。同时,异质结在可见光范围内有良好的光学响应,光吸收系数达到10^(5)cm^(-1),极大提高太阳能利用率,有利于光水解反应进行。因此,二维GeC/InSe异质结是一种有前景的可见光光催化材料。

Based on density functional theory, the electronic, optical and photocatalytic properties of a novel two-dimensional GeC/InSe heterostructure are systematically investigated.The results show that the lattice mismatch ratio of the two-dimensional GeC/InSe heterostructure is 0.98% and its formation energy is-0.135 eV/atom, which proves that the structure of the heterostructure is stable.Secondly, the heterojunction is an indirect semiconductor with a band gap value of 1.82 eV,indicating the type II band alignment.The band offsets of the valence band and conduction band are 1.65 eV and 0.90 eV,respectively.It can effectively reduce the recombination of electrons and holes and improve the photocatalytic performance of the GeC/InSe heterostructure.At the same time, the heterostructure has the favorable optical response in visible light range and the optical absorption coefficient reaches 10^(5)cm^(-1).This greatly improves the utilization of solar energy and is beneficial to the process of hydrolysis reaction.Therefore, the 2 D GeC/InSe heterostructure is a promising visible light photocatalytic material.