Photoluminescence properties of Ca-doped BaMgAl10O17:Eu2+,Mn2+ blue phosphor using BaF2 and CaF2 as co-flux

Ca-doped BaMgAl10O17:Eu2+,Mn2+ (BAM) blue phosphors were synthesized by flux assisted solid-state reaction method using CaF2 and BaF2 as co-flux. Good dispersity and particle size homogenization of hexagonal pure phase BAM were obtained by sintering at 1400 °C. The effects of the Ca2+ ions content on the structure, morphology and photoluminescence properties of the phosphors were studied. The results indicated that the incorporation of Ca could decrease the lattice constant, improve the homogeneity and dispersity and enhance the photoluminescence (PL) intensity of the phosphor effectively. The optimum Ba0.86Ca0.04Mg0.97Al10O17:0.1Eu2+,0.03Mn2+ PL intensity was enhanced for about 30% and relative brightness was improved about 4%. Furthermore, the synthesized BAM and commercial BAM phosphors were annealed for 30 min at 600 °C in air. The Ca-doped phosphors had stronger emission intensity, higher brightness and better chromaticity stability than that of the commercial phosphor. These results indicated that Ca-doped blue phosphors had good potential applications in the commercial tricolor fluorescent lamps as well as in other display and lamps.

Graphical Abstract(a) PL spectra of our BAM phosphors annealed at 600 °C for 30 min with different doping concentrations of CaF2 under 254 nm excitation (Numbers 1, 2, 3, 4, 5, 6 represent the same alphabets phosphors as shown in Fig. 3. Here, the number (1) sample has the similar PL intensity with commercial BAM. The maximal peak intensity is nearby 455 nm position with different CaF2 doping concentrations); (b) The relative brightness curves of commercial BAM (the red solid square in circle) and different CaF2 doped BAMFigure optionsDownload as PowerPoint slide