| Autor: |
Sukgeun Choi, Yong Yan, Kai Zhu, Ji-Sang Park, Ye Yang, Philip A. Parilla, Joseph M. Luther, Su-Huai Wei |
| Rok vydání: |
2016 |
| Předmět: |
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| Zdroj: |
The journal of physical chemistry letters. 6(21) |
| ISSN: |
1948-7185 |
| Popis: |
The electronic structure and related optical properties of an emerging thin-film photovoltaic material CH3NH3PbBr3 are studied. A block-shaped α-phase CH3NH3PbBr3 single crystal with the natural ⟨100⟩ surface is synthesized solvothermally. The room-temperature dielectric function ε = ε1 + iε2 spectrum of CH3NH3PbBr3 is determined by spectroscopic ellipsometry from 0.73 to 6.45 eV. Data are modeled with a series of Tauc-Lorentz oscillators, which show the absorption edge with a strong excitonic transition at ∼2.3 eV and several above-bandgap optical structures associated with the electronic interband transitions. The energy band structure and ε data of CH3NH3PbBr3 for the CH3NH3(+) molecules oriented in the ⟨111⟩ and ⟨100⟩ directions are obtained from first-principles calculations. The overall shape of ε data shows a qualitatively good agreement with experimental results. Electronic origins of major optical structures are discussed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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