Red-emitting LiEuW2O8 phosphor for white emitting diodes prepared by sol-gel process

• Autorzy: Hwang K. S. , Jeon Y. S. , Hwangbo S. , Kim J. T.
• Języki publikacji: EN

Abstrakty

EN

Scheelite-type LiEuW2O8 (LEW) phosphors with the optical function of color conversion from near-UV to red were prepared by sol-gel method using a lithium acetate dehydrate, europium(III) nitrate pentahydrate, and tungsten(VI) chloride as starting materials. Viscous mixing sol was prefired at 300 °C for 120 min in air and then white powder precursor was finally annealed at 500-800 °C for 240 min in Ar. From an X-ray diffraction analysis, all the samples are isostructural and belong to the tetragonal system of scheelite-type. The main emission peak is 5D0 › 7F2 transitions of Eu3+ at 615 nm, other transitions from the 5D0 › 7F1, 5D0 › 7F3 and 5D0 › 7F4 located at 570-700 nm range are weak. The characteristic emission of WO4-2 in LEW is quenched absolutely and only red-light emission of Eu3+ appears. Crystallinity, surface properties and red-emission by near-ultraviolet (395 nm) were improved by high-temperature annealing.

Słowa kluczowe

EN

phosphors; sol-gel; near-UV; red-light emission

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Optica Applicata
• Rocznik: 2009
• Tom: Vol. 39, nr 2
• Strony: 375--382
• Opis fizyczny: bibliogr. 17 poz.,

Twórcy

autor

Hwang K. S.

autor

Jeon Y. S.

autor

Hwangbo S.

autor

Kim J. T.

• Department of Biomedical Engineering, Nambu University, 864-1 Wolgye-dong, Gwangsan-gu, Gwangju 506-824, Korea

Bibliografia

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