Facile Synthesis of (Sr,Ca)₂Si₅N₈:Eu²⁺-Based Red-Emitting Phosphor for Solid-State Lighting

A new facile synthetic route to produce a nitride-based red-emitting phosphor has been established. The (Sr,Ca) 2 Si 5 N 8:Eu 2+ -based multicomponent phosphor was successfully synthesized from the stable SrCO 3 –CaCO 3 –Eu 2 O 3 –Si 3 N 4 system by simple one-step heating at 1600 °C for 4 h in an unpressurized N 2 atmosphere. The synthesized (Sr,Ca) 2 Si 5 N 8:Eu 2+ -based red broadband emitting phosphor exhibited the peak wavelength as long as 661 nm with a practically high external quantum efficiency of 60% under the excitation at 450 nm, while the coexisting secondary phase was inactive under the blue-light excitation, showing no detrimental effects on the photoluminescent properties. The enhanced red emission compared to the unmodified Sr 2 Si 5 N 8:Eu 2+ phosphor enables further improvement of the color rendering properties of the white light-emitting diodes for solid-state lighting applications.