Photoluminescence Properties of Green-Emitting YBO3:Ce3+,Tb3+Phosphor for near UV Excitation

YBO 3 :Ce 3+ ,Tb 3+ phosphor was prepared from rare earth oxides and boric acid by a solid state reaction. The phosphor absorbs near UV light through 4f–5d transitions of Ce 3+ , followed by broad emissions through 5d–4f transitions of Ce 3+ and sharp emissions through 4f–4f transitions of Tb 3+ . Spectroscopic investigations for samples with various Ce 3+ and Tb 3+ concentrations reveal nonradiative energy transfer from Ce 3+ to Tb 3+ . Emission color of the YBO 3 :Ce 3+ ,Tb 3+ varies from blue (0.163, 0.019) to green (0.321, 0.585) depending on the Ce 3+ and Tb 3+ concentrations. The optimized green-emitting Y 0.82 Ce 0.03 Tb 0.15 BO 3 phosphor has an emission color of (0.309, 0.547) with an external quantum efficiency of 76.7%. The photoluminescence intensity of this phosphor at 150°C keeps 87% of its intensity at room temperature, showing sufficient thermal stability for white light emitting diode applications.