Comparison of the luminescent properties of warm-toned long-lasting phosphorescent composites: SiO2/red-emitting color converter@ SrAl2O4:Eu2+, Dy3+ and PMMA/red-emitting color converter@ SrAl2O4:Eu2+, Dy3+

Two kinds of warm-toned (yellow/orange-emitting) long-lasting phosphorescent composites, namely, SiO2/red-emitting color converter@SrAl2O4:Eu2+, Dy3+ (SiO2/RECC@SAOED) and PMMA/red-emitting color converter@SrAl2O4:Eu2+, Dy3+ (PMMA/RECC@SAOED), were prepared in this study. Their morphological and luminescent properties were compared with those of the uncoated SAOED phosphor and analyzed in detail. SiO2/RECC@SAOED and PMMA/RECC@SAOED particles presented a coarse surface with an increased diameter of 12 mu m. In addition to the first emission peak at 525 nm similar to that of the uncoated SAOED, an emission peak occurred in the emission spectra of SiO2/RECC@SAOED and PMMA/RECC@SAOED at 610 and 612 nm, respectively. The chromaticity coordinates of SiO2/RECC@SAOED and PMMA/RECC@SAOED moved to the yellow (x = 0.3769, y = 0.5006) and orange (x = 0.4647, y = 0.4671) areas compared with those of the uncoated SAOED in the green area (x = 0.2781, y = 0.5777). The afterglow decay curve revealed that the afterglow property of SiO2/RECC@ SAOED was better than that of PMMA/RECC@SAOED.