| Autor: |
Htjm Bert Hintzen, Fang Yuqun, Qiu Tongji, YQ Yuan Qiang Li, Aca Anneke Delsing |
| Přispěvatelé: |
Materials and Interface Chemistry, Inorganic Materials & Catalysis |
| Jazyk: |
angličtina |
| Rok vydání: |
2010 |
| Předmět: |
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| Zdroj: |
Journal of Alloys and Compounds, 496(1-2), 614-619. Elsevier |
| ISSN: |
0925-8388 |
| Popis: |
Photoluminescence properties and local electronic structures of rare earth (Eu3+ and Ce3+) activated Sr3AlO4F have been studied. X-ray powder diffraction data indicated that the activator ions of Eu3+ and Ce3+ can be incorporated into the Sr3AlO4F lattice and formed limited solid solutions of Sr3−2xLnxNaxAlO4F (Ln = Eu, Ce) with Na+ as a charge compensator ion. The local structure around Sr sites was initially explored using Eu-activated Sr3AlO4F as a structural probe. Sr3AlO4F:Eu3+ exhibits orange-red emission ranging from 520 to 740 nm with a maximum peak at about 619 nm mainly originating from the 5D0 → 7FJ (J = 0, 1, 2, 3, 4) transitions, indicating that Eu exists mainly in the trivalent state due to a strong oxidative lattice in Sr3AlO4F. Sr3AlO4F:Ce3+ shows an unusual long-wavelength 4f → 5d excitation band of Ce3+ at about 405 nm due to a large crystal field splitting of the 5d levels of Ce3+ in relation to its crystal structure. Under near-UV excitation in the range of 375–405 nm, Sr3AlO4F:Ce3+ exhibits efficient blue-green emission at about 506 nm. Given high absorption and efficient excitation in the near-UV region, Sr3AlO4F:Ce3+ demonstrates a potential blue-green emitting phosphor for applications in white LED lighting. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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