Novel red phosphor of Eu3+, Bi3+ coactivated double tungstates

Eu3+, Bi3+ coactivated double-tungstate phosphors were prepared by the solid-state reaction technique, and their photoluminescent properties were investigated. No concentration quenching of Eu3+ was observed in the series samples of NaLa1-x(WO4)(2):xEu(3+). With the introducing of Bi3+ ions, the intensities of the excitation and emission of these phosphors were increased. The phosphor NaEu0.70(WO4)(2):0.30Bi(3+) showed a broadened excitation band around 400 nm and intensely red emissions under similar to 400 nm light excitation, with the CIE chromaticity coordinates (x = 0.66, y = 0.34). Hence, the novel phosphor NaEu0.70(WO4)(2):0.30Bi(3+) may find application in the fabrication of near-UV InGaN-based LEDs. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim