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

We have synthesized the pure ternary nitride phosphor, LaSi₃ N₅: Ce³⁺from the multicomponent oxide system La ₂ O₃ - CeO₂ - SiO₂, by using the gas-reduction-nitridation method. Highly pure, single-phase LaSi₃ N₅: Ce³⁺powders possessing particle sizes of ∼0.4-0.6 μm were obtained with the processing temperature 1500 °C. The synthesized LaSi₃ N₅: Ce³⁺exhibits tunable blue broadband emission with the dominant wavelength of 464-475 nm and the external quantum efficiency of ∼34%-67% under excitation of 355-380 nm. A high thermal stability of LaSi₃ N₅: 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.