Li Li, Wang Yongjie, Shen Jun, Chang Wenxuan, Jin Tianting, Wei Xiantao, Tian Ya
J Nanosci Nanotechnol. 2016 Apr;16(4):3511-6. doi: 10.1166/jnn.2016.11828.
Tm3+ and Yb3+ codoped LuPO4 phosphors were synthesized by the reverse-strike co-precipitation method. The obtained LuPO4:Tm3+,Yb3+ phosphors were characterized by X-ray diffraction (XRD), diffuse reflectance spectra, photoluminescence (PL) spectra, and decay lifetime to understand the observed near-infrared downconversion (DC) phenomena. The XRD results show that all the prepared phosphors can be readily indexed to the pure tetragonal phase of LuPO4 and exhibit good crystallinity. The experimental results showed that the strong visible emission around 649 nm from Tm3+(1G4 --> 3F4) and near-infrared (NIR) emission around 1003 nm from Yb3+(2F5/2 --> 2F7/2) of LuPO4:Tm3+,Yb3+ phosphors were observed under 468 nm excitation, respectively. The Yb3+ concentration dependence of luminescent properties and lifetimes of both the visible and NIR emissions have also been investigated. The quenching concentration of Yb3+ ions approaches 30 mol%. The DC mechanism is also discussed in detail.
采用反滴共沉淀法合成了Tm3+和Yb3+共掺杂的LuPO4荧光粉。通过X射线衍射（XRD）、漫反射光谱、光致发光（PL）光谱和衰减寿命对所得的LuPO4:Tm3+,Yb3+荧光粉进行了表征，以了解观察到的近红外下转换（DC）现象。XRD结果表明，所有制备的荧光粉均可轻松索引到LuPO4的纯四方相，且结晶度良好。实验结果表明，在468nm激发下，分别观察到了LuPO4:Tm3+,Yb3+荧光粉中Tm3+(1G4→3F4)在649nm附近的强可见发射和Yb3+(2F5/2→2F7/2)在1003nm附近的近红外（NIR）发射。还研究了Yb3+浓度对可见和近红外发射的发光性能和寿命的影响。Yb3+离子的猝灭浓度接近30mol%。还详细讨论了DC机制。
