Novel red phosphor of Eu 3+ , Bi 3+ coactivated double tungstates

Eu 3+ , Bi 3+ coactivated double‐tungstate phosphors were prepared by the solid‐state reaction technique, and their photoluminescent properties were investigated. No concentration quenching of Eu 3+ was observed in the series samples of NaLa 1– x (WO 4 ) 2 : x Eu 3+ . With the introducing of Bi 3+ ions, the intensities of the excitation and emission of these phosphors were increased. The phosphor NaEu 0.70 (WO 4 ) 2 :0.30Bi 3+ showed a broadened excitation band around 400 nm and intensely red emissions under ∼400 nm light excitation, with the CIE chromaticity coordinates ( x = 0.66, y = 0.34). Hence, the novel phosphor NaEu 0.70 (WO 4 ) 2 :0.30Bi 3+ may find application in the fabrication of near‐UV InGaN‐based LEDs. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)