Optimization method for green SrAl2O4:Eu2+,Dy3+ phosphors synthesized via co-precipitation route assisted by microwave irradiation using orthogonal experimental design

Abstract A kind of Eu 2+ and Dy 3+ co-doped strontium aluminate green long-lasting phosphor was synthesized via a coprecipitation synthesis method assisted by microwave irradiation in a weak reductive atmosphere of active carbon. The synthesis conditions were optimized with orthogonal experiments and the optimum technological parameters were obtained. Subsequently, the crystal structure, morphology and optical property of the composites were characterized. X-ray diffraction (XRD) patterns illustrated that the samples were composed of single-phase SrAl 2 O 4 . Scanning electron microscopy (SEM) revealed that the resultant nanoparticles had well-dispersed distribution and flake-like morphology with an average size of about 500 nm in width and 70 nm in thickness. The excitation and emission spectra indicated that excitation broadband chiefly lied in the ultraviolet range and naocrystalline particles emitted strong light at 508 nm corresponding to the typical characteristic 5d–4f transition of Eu 2+ ion under around 325 nm excitation. And the long afterglow photoluminescence of SrAl 2 O 4 :Eu 2+ ,Dy 3+ was observed in the dark with the naked eye after the removal of the excitation light. Furthermore, the microwave method requires a very short heating-time and the energy consumption.