Combustion Synthesis and Photoluminescence Properties of Red-Emitting CaAlSiN(3):Eu(2+) Phosphor for White-LEDs

A combustion synthesis method has been developed for synthesis of Eu(2+) doped CaAlSiN(3) phosphor and its photoluminescence properties were investigated. Ca, Al, Si, and Eu(2)O(3) powders were used as the Ca, Al, Si and Eu sources. The addition of NaN(3), NH(4)Cl and Si(3)N(4) powders was found to increase significantly the product yield. These powders were mixed and pressed into a compact, which was then wrapped up with an igniting agent (i.e., Mg+Fe(3)O(4)). The compact was ignited by electrical heating under a N(2) pressure of ≤1.0 MPa. Effects of these experimental parameters on the product yield were investigated and a reaction mechanism was proposed. The synthesized CaAlSiN(3):Eu(2+) phosphor absorbs light in the region of 200–600 nm and shows a broad band emission in the region of 500–800 nm due to the 4f(6)5d(1) → 4f(7) transition of Eu(2+). The sample doped with Eu(2+) at the optimized molar ratio of 0.04 is efficiently excited by the blue light (460 nm) and generates emission peaking at ~650 nm with peak emission intensity ~106% of a commercially available phosphor, YAG:Ce(3+)(P46-Y3).The internal quantum efficiency of the synthesized phosphor was measured to be 71%, compared to 69% of the YAG:Ce(3+) (P46-Y3).