Dy3+和Ce3+共掺Y3Al5O12荧光粉的制备及发光性质

用高温固相法制备了YAG:5%Dy^3+以及(Ce 0.01 Dy y Y 0.99-y)3A15O12(y=0%,1%,3%,5%,7%,9%)荧光粉。XRD结果表明,NH 4Cl、LiCl、H3BO3三种助熔剂比较,添加H3BO3可有效降低YAG晶体的结晶温度,有效阻止中间相YAlO 3的形成。H3BO3做助熔剂在1450℃煅烧6 h制备的Dy^3+和Ce^3+掺杂Y 3Al 5O 12荧光粉具有单一YAG立方相结构,且随Dy^3+掺杂浓度增加,(420)衍射峰逐渐向小角度偏移。在583 nm监测下;与单掺1%Ce^3+样品比较,Ce^3+与Dy^3+共掺样品在342 nm处的吸收均减弱;与单掺5%Dy^3+样品比较,Ce^3+与Dy^3+共掺样品在351 nm处的吸收明显增强。351 nm激发下,随Dy^3+掺杂浓度增加,Ce^3+与Dy^3+共掺样品中Ce^3+在526 nm处的发射强度逐渐减小,而在583 nm处的发射强度先增加后减弱,这说明351 nm激发下,Ce^3+与Dy^3+共掺样品中存在Ce^3+向Dy^3+的部分能量传递。465 nm激发下,Ce^3+与Dy^3+共掺杂样品中只出现Ce^3+的发射峰,且随Dy^3+浓度增加,Ce^3+发光减弱。当Dy^3+离子浓度为3%时,Ce^3+与Dy^3+共掺样品中Dy^3+相对光强达到最大,此时Ce^3+→Dy^3+能量传递效率为15.7%。405 nm激发下,随Dy^3+掺杂浓度增加,合成粉体中Ce^3+的寿命逐渐减小。经计算,Ce^3+→Dy^3+能量传递临界距离为3.464 nm,为电四极-电四极相互作用的共振能量传递。

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

YAG∶5%Dy^3+and(Ce 0.01 Dy y Y 0.99-y)3A15O 12(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 YAlO 3.The results showed that they were still the cubic phase of the samples for Dy^3+,Ce^3+doped Y 3Al 5O 12 by adding H3BO3 after calcination at 1450℃for 6 h.With the increase of Dy^3+doping concentration,the main diffraction peak(420)shifted to a small angle.Underλem=583 nm,the absorptions of Ce^3+and Dy^3+co-doped samples at 342 nm were decreased than that of only Ce^3+doped sample,and the absorptions at 351 nm significantly enhanced compared with that of only Dy^3+doped sample.Under 351 nm excitation,with the increase of Dy^3+doping concentration,the emission intensities at 526 nm decreased for Dy^3+and Ce^3+co-doped Y 3Al 5O 12 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 Ce^3+to Dy^3+existed.Under 465 nm excitation,Ce^3+and Dy^3+co-doped samples only contained Ce^3+emission peak,and with the increase of Dy^3+concentration,emissions of Ce^3+ions decreased.When the concentration of Dy^3+was 3%,the emission intensity of Dy^3+reached the maximum,and the energy transfer efficiency of Ce^3+→Dy^3+was 15.7%.Under 405 nm excitation,with the increase of Dy^3+concentration,the lifetime of Ce^3+decreased for Ce^3+and Dy^3+co-doped samples.The critical distance of Ce^3+→Dy^3+energy transfer was 3.464 nm,which was the resonance energy transfer of the electric quadrupole-electric quadrupole interaction.