Computational Investigation of the Folded and Unfolded Band Structure and Structural and Optical Properties of CsPb(I1−xBrx)3 Perovskites

Hamid M Ghaithan,Saif M H Qaid,Zeyad A Alahmed,Abdullah S Aldwayyan,Andreas Lyras

doi:10.3390/cryst10050342

Hamid M Ghaithan, Saif M H Qaid + Show 3 more

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https://doi.org/10.3390/cryst10050342

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Journal: Crystals	Publication Date: Apr 27, 2020
Citations: 11	License type: CC BY 4.0

Affiliation: King Saud University, Amran University

Abstract

The structural, electronic, and optical properties of inorganic CsPb(I1−xBrx)3 compounds were investigated using the full-potential linear augmented-plane wave (FP-LAPW) scheme with a generalized gradient approximation (GGA). Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA) and modified Becke–Johnson GGA (mBJ-GGA) potentials were used to study the electronic and optical properties. The band gaps calculated using the mBJ-GGA method gave the best agreement with experimentally reported values. CsPb(I1−xBrx)3 compounds were wide and direct band gap semiconductors, with a band gap located at the M point. The spectral weight (SW) approach was used to unfold the band structure. By substituting iodide with bromide, an increase in the band gap energy (Eg) values of 0.30 and 0.55 eV, using PBE-GGA and mBJ-GGA potentials, respectively, was observed, whereas the optical property parameters, which were also investigated, demonstrated the reverse effect. The high absorption spectra in the ultraviolet−visible energy range demonstrated that CsPb(I1−xBrx)3 perovskite could be used in optical and optoelectronic devices by partly replacing iodide with bromide.

Highlights

Halide perovskite ABX3 has attracted increasing interest as a potential solar cell material because of its simple fabrication techniques and outstanding optoelectronic properties
Numerous researchers have focused on methylammonium lead trihalide perovskite (CH3 NH3 PbX3 ), metal halide perovskite (ABX3, A = Cs, Rb; B = Pb, Sn; X = Cl, Br, I), and CsPbI3, which have shown great potential [7,8]
The PBE-generalized gradient approximation (GGA) and modified Becke–Johnson GGA (mBJ-GGA) potentials were used to calculate the electronic properties of CsPb(I1−x Brx )3 perovskite [23,24]

Summary

Introduction

Halide perovskite ABX3 has attracted increasing interest as a potential solar cell material because of its simple fabrication techniques and outstanding optoelectronic properties. ABX3 perovskite materials have a high absorption coefficient, appropriate band gap (Eg ), and balanced electron and hole mobility [1,2,3,4,5,6]. Numerous researchers have focused on methylammonium lead trihalide perovskite (CH3 NH3 PbX3 ), metal halide perovskite (ABX3 , A = Cs, Rb; B = Pb, Sn; X = Cl, Br, I), and CsPbI3 , which have shown great potential [7,8]. Most of the researchers have studied the structural, electronic, and optical properties of CsPbX3 The efficiency can be increased, as this can affect numerous electronic and optical properties [7]. The structural and electronic properties of all of the Crystals 2020, 10, 342; doi:10.3390/cryst10050342 www.mdpi.com/journal/crystals

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