Synthesis and Photoluminescence Properties of a Blue-Emitting La3Si8N11O4:Eu2+ Phosphor

Eu 2+ -doped La 3 Si 8 N 11 O 4 phosphors were synthesized by the high temperature solid-state method, and their photoluminescence properties were investigated in this work. La 3 Si 8 N 11 O 4:Eu 2+ exhibits a strong broad absorption band centered at 320 nm, spanning the spectral range of 300–600 nm due to 4f 7 → 4f 6 5d 1 electronic transitions of Eu 2+ . The emission spectra show a broad and asymmetric band peaking at 481–513 nm depending on the Eu 2+ concentration, and the emission color can be tuned in a broad range owing to the energy transfer between Eu 2+ ions occupying two independent crystallographic sites. Compared to the Ce 3+ -doped La 3 Si 8 N 11 O 4, the Eu 2+ -doped one shows a larger thermal quenching, predominantly owing to photoionization. Under 320 nm excitation, the internal and external quantum efficiencies are 44 and 33%, respectively.