发光学报, 2014, 35 (8): 911, 网络出版: 2014-08-18
12CaO·7Al2O3/5CaO·3Al2O3∶Sm3+新型红色荧光粉的制备及发光性质
Synthesis and Photoluminescence Characteristics of 12CaO·7Al2O3/5CaO·3Al2O3∶Sm3+ Red Phosphors
红光发射 光致发光 12CaO·7Al2O3 12CaO·7Al2O3 5CaO·3Al2O3 5CaO·3Al2O3 Sm3+ Sm3+ red emitting light photoluminescence
摘要
采用自蔓延燃烧法制备了不同Sm3+掺杂浓度的12CaO·7Al2O3(C12A7∶x%Sm3+)荧光粉。在404 nm近紫外光激发下, 观察到了位于565, 599, 648 nm附近的3个光发射峰, 分别归属于Sm3+的4G5/2→6HJ/2(J=5,7,9)能级跃迁。随着Sm3+掺杂浓度增加, 红光发射强度呈现了先增大后减小的规律, 优化的Sm3+掺杂摩尔分数为1.5%, 发光的浓度猝灭效应可归因于Sm3+之间发生了交叉弛豫过程。采取混相策略, 通过降低初始粉体的煅烧温度至900 ℃获得了12CaO·7Al2O3/5CaO·3Al2O3:1.5%Sm3+(C12A7/C5A3∶Sm3+)混相荧光粉, 进一步提高了红光发射强度。利用变温光致发光谱计算得到混相样品的热激活能约为200 meV, 结果表明该混相荧光粉具有良好的热稳定性。
Abstract
12CaO·7Al2O3 (C12A7∶Sm3+) phosphors with different Sm3+ doping concentrations were synthesized through self-propagating combustion method. Under 404 nm UV excitation, there are three dominating emission peaks observed at 565, 599 and 648 nm, corresponding to the 4G5/2→6HJ/2(J=5,7,9) transitions of Sm3+ respectively. With the increasing of Sm3+ doping concentration, the red emitting intensity exhibited a behavior that increased firstly and then decreased. The optimal Sm3+ ion concentration is 1.5% and the concentration quenching effect is due to the cross-relaxation (CR) processes between the Sm3+ ions. Through adopting mixed-phase strategy, 12CaO·7Al2O3/5CaO·3Al2O3∶1.5%Sm3+ (C12A7/C5A3∶Sm3+) powders were prepared by decreasing the calcining temperature to 900 ℃ and the enhanced red emitting intensity was obtained. The temperature-dependent photoluminescence showed that the thermal activation energy of the mixed-phase sample is about 200 meV and its thermal stability is high.
张新阳, 孙尚前, 严端廷, 张猛, 刘玉学. 12CaO·7Al2O3/5CaO·3Al2O3∶Sm3+新型红色荧光粉的制备及发光性质[J]. 发光学报, 2014, 35(8): 911. ZHANG Xin-yang, SUN Shang-qian, YAN Duan-ting, ZHANG Meng, LIU Yu-xue. Synthesis and Photoluminescence Characteristics of 12CaO·7Al2O3/5CaO·3Al2O3∶Sm3+ Red Phosphors[J]. Chinese Journal of Luminescence, 2014, 35(8): 911.