Sb掺杂LiBiO_3电子结构的第一性原理计算

First-principles calculations for electronic structure of Sb-doped LiBiO_3

通过能带结构、电子态密度、电子局域化函数、Bader电荷等方面的密度泛函理论(DFT)第一性原理计算,对掺杂了Sb的LiBiO3的电子结构进行研究,试图从理论角度探寻合适的光催化材料。计算结果表明,空间群为Pccn的正交LiBiO3为直接半导体,DFT计算带隙为0.23eV,而采用HSE泛函形式的计算带隙为1.18eV,较为接近实验测定值。随着Sb掺杂量的增加,LiBi1-xSbxO3的计算带隙逐渐加大,与纯LiBiO3相比,Sb掺杂体系中出现了具有更强键合作用的Sb-O键,有利于改善体系的光催化性能。

Electronic structure of Sb-doped LiBiO3 has been investigated by performing first-principles calculations within the framework of density functional theory （DFT） on band structure, density of state, electron localization function and Bader charge in order to explore appropriate photocatalytic material in theory. The calculated results show that the orthorhombic LiBiO3 with space group Pccn is a direct semiconductor with a DFT band gap of 0.23 eV. The calculated band gap based on HSE functional is about 1.18 eV, which is close to the experimental value. With the content of Sbis increased, the calculated band gap is enlarged gradually and the stronger Sb-O bonding in- teraction occurs in the Sb-doped system compared with pure LiBiO3, which improves the photocatalytic property of LiBi1-xSbxO3