Luminescence properties of LaPO4:Tb3+,Me3+ (Me=Gd, Bi, Ce) under VUV excitation

The luminescence properties of LaPO4:Tb 3+ ,Me 3+ (Me = Gd, Bi, Ce) were investigated under VUV excitation. The results indicate that only Gd 3+ plays an intermediate role in energy transfer from the host absorption band to Tb 3+ under 147 nm excitation, Bi 3+ and Ce 3+ have no contribution to improving the emission intensity of La0.95PO4:Tb0.05 3+ because the charge transfer band of Bi 3+ is mismatching for the excitation wavelength (147 nm) and Ce 3+ can be oxidized easily. A new band at 135 nm is observed in the excitation spectrum of La0.92PO4:Tb0.05 3+ ,Bi0.03 3+ , which may correlate with the absorption of Bi 2+ .