Exploring Polaronic, Excitonic Structures and Luminescence in Cs4PbBr6/CsPbBr3
| Autor: | Koushik Biswas, Byungkyun Kang |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Photocurrent
Materials science Condensed matter physics Quantum yield 02 engineering and technology Electronic structure 010402 general chemistry 021001 nanoscience & nanotechnology medicine.disease_cause 01 natural sciences 0104 chemical sciences Condensed Matter::Materials Science Quantum dot medicine General Materials Science Physical and Theoretical Chemistry Thin film Ionization energy 0210 nano-technology Luminescence Ultraviolet |
| Zdroj: | The Journal of Physical Chemistry Letters. 9:830-836 |
| ISSN: | 1948-7185 |
| DOI: | 10.1021/acs.jpclett.7b03333 |
| Popis: | Among the important family of halide perovskites, one particular case of all-inorganic, 0-D Cs4PbBr6 and 3-D CsPbBr3-based nanostructures and thin films is witnessing intense activity due to ultrafast luminescence with high quantum yield. To understand their emissive behavior, we use hybrid density functional calculations to first compare the ground-state electronic structure of the two prospective compounds. The dispersive band edges of CsPbBr3 do not support self-trapped carriers, which agrees with reports of weak exciton binding energy and high photocurrent. The larger gap 0-D material Cs4PbBr6, however, reveals polaronic and excitonic features. We show that those lattice-coupled carriers are likely responsible for observed ultraviolet emission around ∼375 nm, reported in bulk Cs4PbBr6 and Cs4PbBr6/CsPbBr3 composites. Ionization potential calculations and estimates of type-I band alignment support the notion of quantum confinement leading to fast, green emission from CsPbBr3 nanostructures embedded in ... |
| Databáze: | OpenAIRE |
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