Photo-luminescent properties of Eu3+ ion-doped Ca4REO(BO3)3 (REdouble bond; length as m-dashLa,Y,Gd)

Europium-doped materials Ca4REO(BO3)3 (RE=La,Y,Gd) were first synthesized by a sol–gel process technique. The reaction temperature of the sol–gel process was 300 °C lower than that of solid-state reaction and the reaction time of sol–gel process was shorter. The photo-luminescence characteristics of Eu-doped Ca4REO(BO3)3 (RE=La,Y,Gd) indicated that all compounds exhibited strong luminescence of 5D0–7F2 at 608 nm under excitation at 242 nm. The emission intensity of phosphors prepared by sol–gel process was higher than those prepared by solid-state reaction; particularly the compound Ca4La0.9Eu0.1O(BO3)3 prepared by sol–gel process presented the highest brightness. SEM images showed that particles prepared by sol–gel process had more regular morphology and smaller grain size.