The Presence of Charge Transfer Defect Complexes in Intermediate Band CuAl1−pFepS2
| Autor: | Adam Kinsella, Matthew Booth, Matthew Watkins, Christopher Dickens |
|---|---|
| Rok vydání: | 2022 |
| Předmět: |
Inorganic Chemistry
semiconductors DFT chalcopyrite defects electronic structure charge transfer nanocrystals F120 Inorganic Chemistry General Chemical Engineering General Materials Science F200 Materials Science F343 Computational Physics Condensed Matter Physics F310 Applied Physics F321 Solid state Physics |
| Zdroj: | Crystals; Volume 12; Issue 12; Pages: 1823 |
| ISSN: | 2073-4352 |
| DOI: | 10.3390/cryst12121823 |
| Popis: | Despite chalcopyrite (CuFeS2) being one of the oldest known copper ores, it exhibits various properties that are still the subject of debate. For example, the relative concentrations of the ionic states of Fe and Cu in CuFeS2 can vary significantly between different studies. The presence of a plasmon-like resonance in the visible absorption spectrum of CuFeS2 nanocrystals has driven a renewed interest in this material over recent years. The successful synthesis of CuAl1−pFepS2 nanocrystals that exhibit a similar optical resonance has recently been demonstrated in the literature. In this study, we use density functional theory to investigate Fe substitution in CuAlS2 and find that the formation energy of neutral [FeCu]2++[CuAl]2− defect complexes is comparable to [FeAl]0 antisites when p≥0.5. Analysis of electron density and density of states reveals that charge transfer within these defect complexes leads to the formation of local Cu2+/Fe2+ ionic states that have previously been associated with the optical resonance in the visible absorption of CuFeS2. Finally, we comment on the nature of the optical resonance in CuAl1−pFepS2 in light of our results and discuss the potential for tuning the optical properties of similar systems. |
| Databáze: | OpenAIRE |
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