BaZrSi(3)O(9):Eu(2+): a cyan-emitting phosphor with high quantum efficiency for white light-emitting diodes

Abstract

In this paper, a cyan-emitting phosphor BaZrSi(3)O(9):Eu(2+) was synthesized and evaluated as a candidate for white light emitting diodes (WLEDs). This phosphor shows strong and broad absorption in 380-420 nm region, and the emission intensity of the optimized BaZrSi(3)O(9):Eu(2+) was found to be 90% and 198% of that of the commercial BaMgAl(10)O(17):Eu(2+) (BAM:Eu(2+)) under excitation at 405 nm and 420 nm, respectively. Upon excitation at 405 nm, the quantum efficiency of the optimized BaZrSi(3)O(9):Eu(2+) is 83% of that of BAM:Eu(2+). The performance of this phosphor was further tested to fabricate white LED lamps. By coating BaZrSi(3)O(9):Eu(2+) with a green-emitting (Ba,Sr)(2)SiO(4):Eu(2+) and a red-emitting CaAlSiN(3):Eu(2+) on a near-ultraviolet (405 nm) LED chip, driven by a 350 mA forward bias current, intense warm white light with a color rendering index of 90 has been produced.