Luminescent properties of KGd1−x(WO4)2:Eux3+ and KGd1−x(WO4)2−y(MoO4)y:Eux3+ phosphors in UV-VUV regions

KGd1−x(WO4)2−y(MoO4)y:Eu3+x(0.1⩽x⩽0.75, y=0 and 0.2) phosphors are synthesized through traditional solid-state reaction and their luminescent properties in ultraviolet (UV) and vacuum ultraviolet (VUV) regions are investigated. Under 147 nm excitation, these phosphors show characteristic red emission with good color purity. In order to improve their emission intensity, the MoO42− (20 wt%) is introduced into the anion of KGd1−x(WO4):Eu3+x. The Mo6+ and Eu3+ co-doped KGd(WO4)2 phosphors show higher emission intensity in comparison with the singly Eu3+-doped KGd(WO4)2 in VUV region. The chromaticity coordination of KGd0.45(WO4):Eu3+0.55 is (x=0.669, y=0.331), while that of KGd0.45(WO4)1.8(MoO4)0.2:Eu3+0.55 is (x=0.666, y=0.334) in VUV region.