Theoretical study on electronic and optical properties of mixed valence perovskite Cs <sub>2</sub> Au <sub>2</sub> <i>X</i> <sub>6</sub> ( <i>X</i> = Cl, Br, I)
Abstrak
Abstract We study the electronic and optical properties of the mixed valence perovskite Cs 2 Au 2 X 6 ( X = Cl, Br, I) using the fully relativistic all-electron calculations. We find that Cs 2 Au 2 X 6 exhibits indirect fundamental band gaps although the differences between the indirect and direct band gaps are small. For the electric field of light perpendicular to the tetragonal c axis, Cs 2 Au 2 Br 6 and Cs 2 Au 2 I 6 exhibit the maximum absorption coefficient of about 20 × 10 4 cm −1 around the photon energy of 2 eV, which is considerably larger than that of CH 3 NH 3 PbI 3 . For the electric field of light parallel to the tetragonal c axis, the absorption coefficient of Cs 2 Au 2 I 6 is comparable to that of CH 3 NH 3 PbI 3 in the main part of the solar spectrum. Furthermore, we estimate the photovoltaic performance of Cs 2 Au 2 X 6 employing the spectroscopically limited maximum efficiency as a metric and discuss its dependence on the film thicknes in detail.
Penulis (2)
Shugo Suzuki
Makoto Tsuyama
Akses Cepat
- Tahun Terbit
- 2019
- Bahasa
- en
- Total Sitasi
- 7×
- Sumber Database
- CrossRef
- DOI
- 10.7567/1347-4065/ab4a3c
- Akses
- Open Access ✓