Luminescence properties of Ce3+/Tb3+/Sm3+ co-doped CaO–SiO2–B2O3 glasses for white light emitting diodes

Ce3+/Tb3+/Sm3+ co-doped CaO–SiO2–B2O3 glasses for white light emitting diodes (W-LEDs) have been prepared by the melt-quenching method. The photoluminescence properties of CaO–SiO2–B2O3 glasses were characterized by the emission and excitation spectra. Blue, green and reddish orange emission bands were observed in the emission spectra of co-doped glass samples. When excited by ultraviolet light the co-doped glasses emit a combination of blue, green and reddish orange emissions giving white light. The relative intensity ratio of the Sm3+ 603 nm emission to the Tb3+ 546 nm emission can be tuned by varying the concentration of the Sm3+ ions. In addition, the emission and excitation spectra show a self-quenching effect of Sm3+ ions and an energy transfer from Tb3+ (5D4) to Sm3+ (4G5/2).