Abstract: A new red-emitting phosphor,Ca₄GdO(BO₃)₃:Eu³⁺,was prepared by the solid-state reaction technique at high temperature and its luminescent properties were investigated.The results show that this phosphor emitted bright red light whether under X-ray,UV or VUV excitation.It has great potential for being explored as a new red-emitting phosphor because it can be easily excited by 254 nm,172 nm and X-ray light and emit bright red light.Its dominant emission peak is located at 610 nm and all other emission lines are very weak.It is observed that there is an energy transfer process between the Gd³⁺ ion and activator(Eu³⁺ ion) and one possible way of energy transfer is connected with the secondary absorption,namley cascade exiction.

Key words: luminescent properties, phosphor, energy transfer