Luminescence Properties of Potential Sr[sub 1−x]Ca[sub x]Ga[sub 2]S[sub 4]:Eu Green- and Greenish-Yellow-Emitting Phosphors for White LED

Abstract

We report the optical properties and morphological structure of potential green phosphors ͑Sr 1−x Ca x Ga 2 S 4 :Eu, x = 0.0-1.0͒ for application in phosphor-converted three-band white light emitting diodes ͑LEDs͒. A series of Sr 1−x Ca x Ga 2 S 4 :Eu phosphors was synthesized using NaBr-aided solid-state reactions in a flowing H 2 S stream. They all crystallized with the orthorhombic PbGa 2 Se 4 phase, and their emissions were efficiently excited up to 480 nm. The optical and morphological suitability of Sr 1−x Ca x Ga 2 S 4 :Eu phosphors is discussed in terms of their application as coatings for altering the color of blue LEDs.

Nitridosilicate und Oxonitridosilicate: von keramischen Materialien zu struktureller und funktioneller Diversität

“…Dieser Fortschritt führte zu einem Bedarf an geeigneten Lumineszenzmaterialien (Leuchtstoffen) für die Erzeugung von weißem Licht, was normalerweise erreicht wird durch: 1) die Verwendung von drei einzelnen monochromatischen LEDs (blau, grün, rot); 2) die Kombination einer ultravioletten LED mit blauen, grünen und roten Leuchtstoffen; oder 3) die Verwendung einer blauen LED zur optischen Anregung von gelben oder grünen und roten Leuchtstoffen. [94] [178][179][180] Aluminate, [180] Sulfide [180,181] und Fluoride [182,183] [89] Man kennt heute mehrere seltenerddotierte (Oxo)nitridosilicate, die interessante Lumineszenzeigenschaften zeigen. Dieser Aufsatz gibt nur einen kurzen Überblick über einige der vielversprechendsten Leuchtstoffe.…”

Silicon-based oxynitride and nitride phosphors for white LEDs—A review

“…The phosphor most commonly utilized in bichromatic white LEDs is the yellow-emitting (Y 1Àa Gd a ) 3 (Al 1Àb Ga b ) O 12 :Ce 3+ (YAG:Ce) [1]. Other types of phosphor such as orthosilicates [3,4], aluminates [5], and sulfides [5,6] have also been used in white LEDs. However, most oxide-based phosphors have low absorption in the visible-light spectrum, making it impossible for them to be coupled with blue LEDs.…”

Solvent effect on optical properties of hydrated lanthanide tris-acetylacetone

“…In recent decades, lanthanide tris-b-diketones have been receiving much attention because of their bright optical properties [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] in visible region. Lanthanide tris-bdiketones are of particular interest, since some of them possess bright luminescence (Eu(III) and Tb(III)) in visible region due to radiative 4f-4f transitions of the Ln(III) ion in solution as well as in solid state at room temperature [6][7][8][9][10][11][12][13][14].…”

“…Lanthanide tris-bdiketones are of particular interest, since some of them possess bright luminescence (Eu(III) and Tb(III)) in visible region due to radiative 4f-4f transitions of the Ln(III) ion in solution as well as in solid state at room temperature [6][7][8][9][10][11][12][13][14]. Lanthanide ions have a number of efficient and narrow f-f transitions in the visible region whose position is insensitive to their materials due to the shielding effects of outer 5s and 5p electrons [1,4,5,15,16].…”