文献类型：期刊文献

英文题名：Pure near-infrared to near-infrared upconversion of multifunctional Tm3+ and Yb3+ co-doped NaGd(WO4)2 nanoparticles

作者：Wang, Zhaofeng[1,2];Li, Yezhou[1,2];Jiang, Qi[3];Zeng, Huidan[3];Ci, Zhipeng[4];Sun, Luyi[1,2]

机构：[1]Univ Connecticut, Inst Mat Sci, Dept Biomol & Chem Engn, Storrs, CT 06269 USA;[2]Univ Connecticut, Inst Mat Sci, Polymer Program, Storrs, CT 06269 USA;[3]E China Univ Sci & Technol, Sch Mat Sci & Engn, Minist Educ, Key Lab Ultrafine Mat, Shanghai 200237, Peoples R China;[4]Lanzhou Univ, Sch Phys Sci & Technol, Dept Mat Sci, Lanzhou 730000, Peoples R China

年份：2014

卷号：2

期号：22

起止页码：4495

外文期刊名：JOURNAL OF MATERIALS CHEMISTRY C

收录：;EI(收录号：20142117754351);WOS:【SCI-EXPANDED(收录号:WOS:000336826500020)】；

基金：This research is sponsored by the National Science Foundation (Partnerships for Research and Education in Materials, DMR-1205670), the Air Force Office of Scientific Research (no. FA9550-12-1-0159), and the Faculty Large Grant from the University of Connecticut. H. Z. acknowledges the financial support from the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Sodium compounds - Synthesis (chemical) - Ytterbium compounds - Infrared devices - Light scattering - Nanoparticles

摘要：In this work, Tm3+ and Yb3+ co-doped NaGd(WO4)(2) nanoparticles were synthesized via surfactant-assisted hydrothermal reactions. The structural analysis indicates that Tm3+ and Yb3+ ions have been doped into the NaGd(WO4)(2) host by occupying the Gd3+ sites. The as-prepared NaGd(WO4)(2):Tm3+,Yb3+ nanomaterials are spherical particles of approximate sizes in the range 50-80 nm. The upconversion spectra results suggest that the NaGd(WO4)(2):Tm3+,Yb3+ nanoparticles exhibit pure or virtually pure near-infrared to near-infrared upconversion luminescence when excited by a 975 nm laser. This phenomenon is significant for nanoparticles with applications in bio-imaging, because both excitations and emissions in the near-infrared region reduce the autofluorescence and light scattering from biological tissues. On the basis of the upconversion and Raman spectra, a possible mechanism for the high purity near-infrared upconversion emission is proposed. Moreover, the NaGd(WO4)(2):Tm3+ Yb3+ nanoparticles also exhibit paramagnetism, which is promising for bio-separation applications.