Luminescent property of Y2O2S:Eu3+ nanophosphors prepared by molten salt synthesis

Red nanofluorescent materials based on Y2O2S: Eu3+ were prepared by the molten salt method. Multiple small-sized Y2O2S sphere-shpaed particles ranging from 100 nm to 200 nm were prepared using different types of yttrium salts (Y(NO3)3·6H2O, YCl3, Y2(CO3)3·3H2O and Y2(C2O4)·6H2O). Based on a fluorescence performance test, their fluorescence properties reached up to 275 nm. We chose NaCl-Na2CO3 as the molten salt, and with all other experimental parameters being equal, the Y2O2S:Eu3+ particles produced were more uniform, with better diffraction properties and a smoother surface. With a molar ratio of 30 for molten salt and yttrium salt, more spherical Y2O2S:Eu3+ particles were produced small and sand homogeneous size. By using different dosage of molten salt, it was found that higher dosage of resulted in smaller particles with weaker fluorescence properties. Finally, by comparing the molten salt method with production by solid-state reaction, we found that the luminescence intensity of the product increased 20％compared to products obtained with the solid-state reaction.