Density Functional Study of Cubic, Tetragonal, and Orthorhombic CsPbBr3 Perovskite

Hamid M Ghaithan; Zeyad A Alahmed; Saif M H Qaid; Mahmoud Hezam; Abdullah S Aldwayyan

doi:10.1021/acsomega.0c00197

Density Functional Study of Cubic, Tetragonal, and Orthorhombic CsPbBr₃ Perovskite

ACS Omega. 2020 Mar 24;5(13):7468-7480. doi: 10.1021/acsomega.0c00197. eCollection 2020 Apr 7.

Authors

Hamid M Ghaithan^{1

2}, Zeyad A Alahmed¹, Saif M H Qaid¹, Mahmoud Hezam³, Abdullah S Aldwayyan^{1

4}

Affiliations

¹ Physics and Astronomy Department, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
² Physics Department, College of Education and Linguistic, Amran University, Amran, Yemen.
³ King Abdullah Institute for Nanotechnology, King Saud University, P.O. Box 2454, Riyadh 11451, Saudi Arabia.
⁴ K.A.CARE Energy Research and Innovation Center at Riyadh, P.O. Box 2022, Riyadh 11454, Saudi Arabia.

Abstract

Cesium lead bromide (CsPbBr₃) perovskite has recently gained significance owing to its rapidly increasing performance when used for light-emitting devices. In this study, we used density functional theory to determine the structural, electronic, and optical properties of the cubic, tetragonal, and orthorhombic temperature-dependent phases of CsPbBr₃ perovskite using the full-potential linear augmented plane wave method. The electronic properties of CsPbBr₃ perovskite have been investigated by evaluating their changes upon exerting spin-orbit coupling (SOC). The following exchange potentials were used: the local density approximation (LDA), Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA), Engel-Vosko GGA (EV-GGA), Perdew-Burke-Ernzerhof GGA revised for solids (PBEsol-GGA), modified Becke-Johnson GGA (mBJ-GGA), new modified Becke-Johnson GGA (nmBJ-GGA), and unmodified Becke-Johnson GGA (umBJ-GGA). Our band structure results indicated that the cubic, tetragonal, and orthorhombic phases have direct energy bandgaps. By including the SOC effect in the calculations, the bandgaps computed with mBJ-GGA and nmBJ-GGA were found to be in good agreement with the experimental results. Additionally, despite the large variations in their lattice constants, the three CsPbBr₃ phases possessed similar optical properties. These results demonstrate a wide temperature range of operation for CsPbBr₃.