Blue-emitting LaSi3N5:Ce3+ fine powder phosphor for UV-converting white light-emitting diodes

We have synthesized the pure ternary nitride phosphor, LaSi3N5:Ce3+ from the multicomponent oxide system La2O3-CeO2-SiO2, by using the gas-reduction-nitridation method. Highly pure, single-phase LaSi3N5:Ce3+ powders possessing particle sizes of similar to 0.4-0.6 mu m were obtained with the processing temperature < 1500 degrees C. The synthesized LaSi3N5:Ce3+ exhibits tunable blue broadband emission with the dominant wavelength of 464-475 nm and the external quantum efficiency of similar to 34%-67% under excitation of 355-380 nm. A high thermal stability of LaSi3N5:Ce3+ compared to the existing La-Si-O-N hosts was demonstrated, indicating the promising applicability as a blue-emitting phosphor for UV-converting white light-emitting diodes.