Abstract:
A novel red phosphor Lu3(1-x)Sc2Ga3O12: xEu3+(0 ≤ x ≤ 0.3) was successfully prepared by high temperature solid state method. The Lu2.4Sc2Ga3O12: 0.2Eu3+ phosphor shows strong high internal quantum efficiency and thermal stability with values of 64.79 % and 87.0 %, respectively. Based on Lu2.4Sc2Ga3O12: 0.2Eu3+ phosphor, the partial replacement of Lu3+ ions in the host by Gd3+ / Y3+ ions changes the local crystal field environment of Eu3+ ions, resulting in wonderful changes in the luminous center, and the luminous intensity at 593 nm is increased by 3.66 and 3.54 times, respectively. The decay time of Eu3+ ions is analyzed from the perspective of dynamics, and the reasons for the enhancement of luminescence after partial replacement of Lu3+ ions are discussed in detail from two aspects of phosphor structure and crystal field effect around Eu3+ ions. In addition, with the substitution of Gd3+ / Y3+ ions, the thermal stability of the sample is 90.3 %/89.4 % with excellent low thermal quenching. The thermal quenching mechanism is described by combining Debye temperature and activation energy. The sample also has a high internal quantum efficiency IQE=79.03 % / 78.24 %. Finally, under the excitation of 365 nm chip, the phosphors of Lu2.34Sc2Ga3O12: 0.2Eu3+, 0.02Gd3+ and Lu2.34Sc2Ga3O12: 0.2Eu3+, 0.02Y3+ synthesized R-LED device has extremely high color rendering index, Ra is 78.23/77.15 and color temperature is 1640.38 K/1642.97 K. The experimental results show that the Lu2.34Sc2Ga3O12: 0.2Eu3+, 0.02Gd3+ / Y3+ phosphors prepared has a wide application prospect in w-LED devices.
摘要:
采用高温固相法制备了新型红色荧光粉Lu3(1-x)Sc2Ga3O12:xEu3+(0≤x≤0.3)。Lu2.4Sc2Ga3O12:0.2Eu3+荧光粉表现出较高的内部量子效率和热稳定性,分别为64.79%和87.0%,分别。基于Lu2.4Sc2Ga3O12:0.2Eu3+荧光粉,Gd3+/Y3+离子对宿主中Lu3+离子的部分替代改变了Eu3+离子的局部晶体场环境,导致发光中心的奇妙变化,593nm处的发光强度分别提高了3.66和3.54倍,分别。从动力学角度分析了Eu3+离子的衰减时间,并从荧光粉结构和Eu3+离子周围的晶体场效应两个方面详细讨论了部分取代Lu3+离子后发光增强的原因。此外,用Gd3+/Y3+离子取代,样品的热稳定性为90.3%/89.4%,具有优异的低热淬火性能。通过结合德拜温度和活化能来描述热淬火机理。样品还具有高的内部量子效率IQE=79.03%/78.24%。最后,在365nm芯片的激发下,Lu2.34Sc2Ga3O12的荧光粉:0.2Eu3+,0.02Gd3+和Lu2.34Sc2Ga3O12:0.2Eu3+,0.02Y3+合成R-LED器件具有极高的显色指数,Ra为78.23/77.15,色温为1640.38K/1642.97K。实验结果表明,Lu2.34Sc2Ga3O12:0.2Eu3+,制备的0.02Gd3+/Y3+荧光粉在w-LED器件中具有广阔的应用前景。