Details

Autor(en) / Beteiligte

• Zhao, Hui

Titel

Density Functional Theory Study of Electronic and Optical Properties of Perovskite Derivative Cs3Sb2I9

Ist Teil von

• Russian Journal of Physical Chemistry A, 2023-10, Vol.97 (10), p.2181-2188

Ort / Verlag

Moscow: Pleiades Publishing

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We have systematically investigated the structural, electronic and optical properties of perovskite derivative Cs 3 Sb 2 I 9 under various pressures utilizing first-principles calculations within density functional theory. The calculated lattice constants are in good agreement with previous results. From the analysis of electronic properties, we concluded that Cs 3 Sb 2 I 9 is a direct band gap semiconductor with a value of 1.92 eV. The research of bonding properties shows that the bonds of Cs 3 Sb 2 I 9 are covalent bonds, which can increase the stability of the compound. It is noteworthy that the band gap decreases with the pressure increase in the range of 0–20 GPa, and the valence band maximum (VBM) with hybrid characteristics and mainly consisted of I 5 p orbital and a small amount of Sb 5 s orbital. Further, we have evaluated for the first time dielectric and optical properties of this compound. In the energy range from 0 to 20 eV, all the optical spectra shift to lower energy as the pressure increases, and the decrement of the absorption coefficient corresponds to the change of the band gap. We found that the optical properties of perovskite derivative Cs 3 Sb 2 I 9 undergo a red shift with increasing pressure. This is the first quantitative theoretical prediction of the optical properties of Cs 3 Sb 2 I 9 compound, and it still awaits experimental confirmation.