PbS插层层状BiOBr的第一性原理计算

First Principle Calculation of PbS Intercalated Layered BiOBr

构建了Pb S插层层状Bi OBr晶胞(Pb S-Bi OBr)。基于第一性原理对Bi OBr和Pb S-Bi OBr的结构进行了优化计算,在此基础上,计算、分析并比较了Bi OBr和Pb S-Bi OBr的电子结构以及光学性质。结果表明,在Pb S-Bi OBr中,Pb同时与两个Br、两个S原子形成共价键而致a、b轴缩短,c轴拉长;与Bi OBr相比,Pb S-Bi OBr价带顶因S3p电子参与杂化而提升并致带隙变窄,所有光学性质均发生红移,其峰值均有所降低。

A kind of Pb S intercalated layered Bi OBr cell(Pb S-Bi OBr) was constructed. The crystal structure of Bi OBr and Pb S-Bi OBr was optimized based on the first principle. Then the electronic structure and optical properties of Bi OBr and Pb S-Bi OBr was calculated and analyzed. The results showed that, in Pb S-Bi OBr, covalent bonds formed between Pb and two Br, and between Pb and two S atoms, and a and b axis was shortened and c axis was elongated. Compared with Bi OBr, Pb S-Bi OBr's bandgap is narrowed by the valence band ascending due to the hybridization of S3 p, and all the related optical properties are red shifted and the peak value of optical properties decrease.