Manipulating upconversion emission of cubic BaGdF5:Ce3+/Er3+/Yb3+ nanocrystals through controlling Ce3+ doping

作者：Huang, Xinyang^*; Jiang, Liang; Li, Xiaoxia; He, Aiqun

来源：Journal of Alloys and Compounds, 2017, 721: 374-382.

DOI：10.1016/j.jallcom.2017.05.320

• BaGdF5:Ce3+/Er3+/Yb3+ nanocrystals
• Low-temperature molten-salt method
• Energy transfer
• Emission mechanisms

Low -temperature molten -salt method and the NH4NO3 flux were 'developed to synthesize quasi spherical cubic BaGdF5:Ce3+/Er3+/Yb3+ nanocrystals with the average diameter of 30 nm. The optimum doping concentrations of Er3+ and Yb3+ are determined to 2 and 20 mol%, respectively. The introduction of Ce3+ in BaGdFs: Er3+/Yb3+ nanocrystals deduced a huge variation of the profile of the UC emission under 976 nm laser irradiation. The strong ultraviolet UC emission of 330-380 nm is due to the overlap of (4)G(7/2),K-2(15/2),(4)G(9/2) -> I-4(15/2) transitions of Er3+, and strong blue one locating at 440-480 nm is attributed to the overlap of F-4(3/2)4,F-5/2 -> I-4(15/2) and (4)G(7/2),K-2(15/2),(4)G(9/2) -> I-4(13/2) transitions of Er3+, respectively. The UC emission mechanism and energy transfer process of BaGdF5:Ce3+/Er3+Yb3+ nanocrystals were provided in detail and demonstrated by the fluorescence decay curves and pumping power dependent UC emission spectra. This work not only demonstrates a rational approach to tailor UC emission (red, blue and ultraviolet) by tuning doping ions and concentration, but also for better understanding of their essential UC luminescence properties.

• 出版日期2017-10-15
• 单位江西财经大学