Effect of Ce3+ on the Luminescence Properties of SrAl2O4:Eu2+, Dy3+ Persistent Phosphors for Alternating Current Driven Light-Emitting Diodes

SrAl2O4:Eu2+, Dy3+ has been widely studied as a classical persistent phosphor due to its stability and long green-afterglow duration. In this study, a series of Ce3+ co-doped SrAl2O4:Eu2+, Dy3+ phosphors were prepared by the traditional solid state reaction method, sintering under Ar + 5% H2 atmosphere in the temperature range of 1300–1500°C. The effect of Ce3+ co-doping on luminescence performance of SrAl2O4:Eu2+, Dy3+ was investigated at Ce3+ concentration of 0–0.3 at %. Under excitation wavelengths of 365, 400 and 460 nm, respectively, the luminescence intensity was found to increase linearly with rise of sintering temperature or Ce3+ doping concentrations. It was ascribed to the sufficient crystallization at high sintering temperature as well as the high absorption cross section of Ce3+ ion. Besides, the Ce3+ co-doping speeds up the afterglow time without introducing the emission wavelength shift. Therefore, Ce3+ co-doped SrAl2O4: Eu, Dy is a promising high efficient phosphor for compensated the dark period in alternating current driven light-emitting diodes (AC-LED) lighting.