Blue emission of Ce³⁺ in lanthanide silicon oxynitride phosphors

Ce³⁺-activated lanthanide silicon oxynitride (La₅Si₃O₁₂N, La₄SiO₇N₂, LaSiO₂N, and La₃Si₈O₄N₁₁) phosphors were prepared by firing the mixture of La₂O₃, Si₃N₄, SiO₂, and CeO₂ at 1500–1600 °C under a 0.5 MPa nitrogen atmosphere. Diffuse reflection spectrum, photoluminescence spectra, and temperature-dependent luminescence of these phosphors are presented in this work. A blue emission of Ce³⁺ in all lanthanide silicon oxynitrides was observed under ultraviolet irradiation, which is strongest in La₃Si₈O₄N₁₁:Ce³⁺. The concentration quenching and thermal quenching of the samples were discussed.