Upconversion emission of SrYbF5:Er3+ nanosheets modified by Tm3+ ions

Abstract Through a hydrothermal route, the Er 3+ and Tm 3+ co-doped SrYbF 5 nanosheets were synthesized. The resulting samples were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy and luminescence spectra. Under the excitation of 980 nm laser irradiation, the upconversion emissions of Tm 3+ ions centered at 474 nm ( 1 G 4 → 3 H 6 ), 679 nm ( 3 F 2 → 3 H 6 ), 699 nm ( 3 F 3 → 3 H 6 ), 803 nm ( 3 H 4 → 3 H 6 ) and emissions of Er 3+ ions centered at 522 nm ( 2 H 11/2 → 4 I 15/2 ), 543 nm ( 4 S 3/2 → 4 I 15/2 ), 654 nm ( 4 F 9/2 → 4 I 15/2 ) were observed. The upconversion emissions of Er 3+ ions were adjusted by the concentration of Tm 3+ ions. The energy transfer mechanisms among Er 3+ -Yb 3+ -Tm 3+ in SrYbF 5 nanosheets were discussed.