Luminescence properties of La2Si6O3N8:Eu2+ phosphors prepared by spark plasma sintering

• Fabrication of Eu-doped La2Si6O3N8 phosphors by spark plasma sintering method.
• La2Si6O3N8:Eu2+ phosphors exhibit a bluish-green emission under NUV excitation.
• Post-annealing and acid-washing improved the emission intensity of the phosphors.

Bluish green-emitting La2Si6O3N8:Eu2+ phosphors were synthesized by a spark plasma sintering (SPS) method, and the effects of sintering temperature, Eu doping concentration, post-annealing, and acid washing on the photoluminescence (PL) properties were investigated. A single phase La2Si6O3N8:Eu2+ was successfully achieved at 1700 °C by SPS. As-synthesized La2Si6O3N8:Eu2+ phosphors exhibited a single band emission centered at 483–496 nm under the excitation of 370 nm. The post-annealing and acid-washing significantly improved the emission intensity by increasing the crystallinity, reducing the carbon content, and changing the morphology of particles. Unexpectedly, La2Si6O3N8:Eu2+ phosphors showed a strong thermal quenching.