Phase-, shape- and size-controlled synthesis of NaYF_4:Yb~(3+),Er~(3+) nanoparticles using rare-eart

来源 :Journal of Rare Earths | 被引量 : 0次 | 上传用户:dfg4g4354yh
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Hexagonal-phase NaYF4:Yb3+,Er3+ upconversion nanoparticles(UCNPs) with a uniform size distribution were synthesized using rare-earth acetates as precursors. The effects of reaction temperature and time on the phase transition process of the UCNPs were systematically studied. Based on the evolution of particle morphology and phase with temperature and time, it could be concluded that the transition from cubic phase to hexagonal phase for NaYF4:Yb3+,Er3+ UCNPs was consistent with a dissolution/recrystallization process. In addition, the shape and size of the UCNPs could be controlled by adjusting the solvent ratio and the precursor ratio, respectively. Hexagonal-phase NaYF4: Yb3 +, Er3 + upconversion nanoparticles (UCNPs) with a uniform size distribution were synthesized using rare-earth acetates as precursors. The effects of reaction temperature and time on the phase transition process of the UCNPs were systematically studied. Based on the the evolution of particle morphology and phase with temperature and time, it could be concluded that the transition from cubic phase to hexagonal phase for NaYF4: Yb3 +, Er3 + UCNPs was consistent with a dissolution / recrystallization process. In addition, the shape and size of the UCNPs could be controlled by adjusting the solvent ratio and the precursor ratio, respectively.
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