Luminescent Properties of Dy3+, Ce3+ Co-doped Y3Al5O12 Phosphors

YAG:5%Dy3+ and (Ce0.01DyyY0.99-y)3A15O12 (y=0%,1%,3%,5%,7%,9%) phosphors were prepared by high temperature solid-state method. XRD results showed that the addition of H3BO3 could effectively reduce the crystallization temperature of YAG crystal and prevent the formation of the intermediate phase YAlO3. The results showed that they were still the cubic phase of the samples for Dy3+, Ce3+ doped Y3Al5O12 by adding H3BO3 after calcination at 1 450 ℃ for 6 h. With the increase of Dy3+ doping concentration, the main diffraction peak (420) shifted to a small angle. Under λem=583 nm, the absorptions of Ce3+ and Dy3+ co-doped samples at 342 nm were decreased than that of only Ce3+ doped sample, and the absorptions at 351 nm significantly enhanced compared with that of only Dy3+ doped sample. Under 351 nm excitation, with the increase of Dy3+ doping concentration, the emission intensities at 526 nm decreased for Dy3+ and Ce3+ co-doped Y3Al5O12 samples, but the emission intensities at 583 nm first increased and then decreased, which indicated that under the excitation of 351 nm, part of the energy transfer from Ce3+ to Dy3+ existed. Under 465 nm excitation, Ce3+ and Dy3+ co-doped samples only contained Ce3+ emission peak, and with the increase of Dy3+ concentration, emissions of Ce3+ ions decreased. When the concentration of Dy3+ was 3%, the emission intensity of Dy3+ reached the maximum, and the energy transfer efficiency of Ce3+→Dy3+ was 15.7%. Under 405 nm excitation, with the increase of Dy3+ concentration, the lifetime of Ce3+ decreased for Ce3+ and Dy3+ co-doped samples. The critical distance of Ce3+→Dy3+ energy transfer was 3.464 nm, which was the resonance energy transfer of the electric quadrupole-electric quadrupole interaction. © 2020, Science Press. All right reserved.