Synthesis and characterization of Sr3Al2O6:Eu2+, Dy3+phosphors prepared by sol-gel-combustion processing
- Available Online: 30/10/2009
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Key words:
- Sr3Al2O6:Eu2+ /
- Dy3+ phosphors /
- red luminescence /
- sol-gel-combustion method
Abstract: A type of red luminescent Sr3Al2o6:Eu2+, Dy3+ phosphor powder is synthesised by sol-gel-combustion processing, with metal nitrates used as the source of metal ions and citric acid as a chelating agent of metal ions. By tracing the formation process of the sol-gel, it is found that it is necessary to reduce the amount of NO-3 by dropping ethanol into the solution for forming a stable and homogeneous sol-gel. Thermogravimetric and Differential Scanning Calorimeter Analysis, x-ray diffractionmeter, scanning electron microscopy and pbotoluminescence spectroscopy are used to investigate the luminescent properties of the as-synthesised Sr3Al2o6:Eu2+, Dy3+. The results reveal that the Sr3Al2o6crystallises completely when the combustion aSh is sintered at 1250 ℃. The excitation and the emission spectra indicate that the excitation broadband lies mainly in a visible range and the phosphors emit a strong light at 618 nm under the excitation of 472 nm. The afterglow of (Sr0.94Eu0.03Dy0.03)3Al2O6 phosphors sintered at 1250 ℃ lasts for over 1000s when the excited source is cut off.