Mechanism of concentration quenching of BaMgAl/sub 10/O/sub 17/:Eu/sup 2+/ blue phosphor for plasma display panel

A phosphor for plasma display panel, BaMgAl/sub 10/O/sub 17/:Eu/sup 2+/, showing a blue emission band at about 450 nm, was prepared by a solid-state reaction using BaCO/sub 3/, Al/sub 2/O/sub 3/, MgO, Eu/sub 2/O/sub 3/ as starting materials with flux AlF3. Concentration quenching decreased of emission intensity was shown at about 2.25/spl sim/2.3 wt% of Eu due to a decrease in the critical distance for energy transfer of inter-atomic Eu. Through the combined Rietveld refinement, the occupancy of Eu and Mg was 0.082 and 0.526 at critical concentration. The critical distance of Eu/sup 2+/in BAM was 18.8 /spl Aring/ at 2.25% Eu of the concentration quenching. Furthermore, c/a ratio was decrease to 3.0 wt% and no more change was observed over that concentration. The maximum electron energy density was found that the modeling of /spl beta/-alumina structure in BaMgAl/sub 10/O/sub 17/:Eu/sup 2+/correct coincided showing Ba, Eu, O atoms of z=1/4 mirror plane.