Color-tunable self-activated oxyfluoride phosphors induced by anion-defect with cation-disorder

Cation-disordered oxyfluoride materials, Sr3-p-qBapNaqAl1-zSnzO4F (p = 0-0.7 and q, z = 0, 0.05) and Sr2.975-pBapNa0.05AlO4F (p = 0-0.7), were prepared via solid-state reactions and subsequently induced with defects under appropriate reduction conditions. The anion-deficient self-activating phosphors can be identified using broadband-shaped emissions ranging from 300 to 700 nm when excited with ultraviolet (UV) light. The luminescence properties of the defect-induced self-activating phosphors were examined using cation-disordered [(Sr,Ba) (Al,Sn)O4]3- and [(Sr,Na)2F]3+ clusters in the oxyfluoride lattice. The luminescent emissions of Sr2.45Ba0.5Na0.05Al0.95Sn0.05O4-αF1-δ phosphors were significantly enhanced by the combination of the cation disorder with anion defect. Color-tunable emissions in the defect-induced self-activating Sr2.45Ba0.5Na0.05Al0.95Sn0.05O4-αF1-δ phosphor were obtained. The desired Commission Internationale de I'Eclairage (CIE) values corresponding to the spectral emission from blue to white and yellow regions of the spectra were attained by exciting the defect-induced self-activating Sr2.45Ba0.5Na0.05Al0.95Sn0.05O4-αF1-δ phosphors with UV light.