LAUSR

Abstract The quality of YAG:Ce phosphors will influence the luminescent performance of white LEDs devices. Therefore, in this study, we attempted to synthesis high quality YAG:Ce phosphors using coprecipitation method. YAG:Ce precursors were synthesized through coprecipitation at different rotational speeds of an electromagnetic stirrer and then heated at different calcination temperatures ranging from 900 to 1300 °C. X-ray diffraction analysis revealed that phase-pure phosphors could be obtained from the precursors synthesized at 400 rpm and then calcined at 1300 °C. The emission intensity of Ce-doped YAG phosphor increased with the calcination temperature, owing to the higher crystallinity of the YAG phase. Moreover, at the same calcination temperature from 900 to 1300 °C, the maximum fluorescence intensity at approximately 540 nm of the YAG:Ce nanopowders synthesized at 400 rpm increased three to five times that of the YAG:Ce nanopowders synthesized at 200 rpm. The optimal luminescence performance of the YAG:Ce nanopowders was obtained at 400 rpm and at a calcination temperature of 1300 °C. The results of luminescence performance indicated YAG:Ce nanopowders has a great potential for development of white LEDs devices.