Article

Optoelectronic and elastic properties of metal halides double perovskites Cs2InBiX6 (X = F, Cl, Br, I)

Muhammad SaeedState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaIzaz Ul HaqCenter for Computational Materials Science, Department of Physics, University of Malakand, Chakdara, PakistanShafiq Ur RehmanCollege of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, ChinaAkbar AliCenter for Computational Materials Science, Department of Physics, University of Malakand, Chakdara, PakistanWajid Ali ShahCenter for Computational Materials Science, Department of Physics, University of Malakand, Chakdara, PakistanZahid AliCenter for Computational Materials Science, Department of Physics, University of Malakand, Chakdara, PakistanQasim KhanCollege of Electronic Science and Technology, Shenzhen University, Shenzhen 518000, ChinaImad KhanCenter for Computational Materials Science, Department of Physics, University of Malakand, Chakdara, Pakistan

2021en

ABI

Abstract

Structural geometry, electronic band gaps, density of states, optical and mechanical properties of double perovskite halides Cs2InBiX6 (X = F, Cl, Br, I) are investigated using the density functional theory. These compounds possess genuine perovskite stoichiometry, evaluated using various geometry-based indices like tolerance factor, octahedral factor, and formation energy. The fundamental electronic band gaps are direct and valued in the range 0.80–2.79 eV. These compounds have narrow band gaps (except Cs2InBiF6) due to strong orbital coupling of the cations. The valence band maximum and conduction band minimum are confirmed to be essentially of In 5s and Bi 6p characters, respectively. The splitting of Bi 6p bands due to strong spin-orbit coupling causes reduction in the band gaps. These compounds have large dispersion in their bands and very low carrier effective masses. The substitution of halogen atoms has great influence on the optical properties. The mechanical properties reveal that Cs2InBiX6 (X = F, Cl, Br, I) satisfy the stability criteria in cubic structures.

Identifiers

DOI: 10.3788/col202119.030004

Citations and references

Cited by 20 references

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