Luminescence properties of alkali metal ions sensitized CaFCl:Tb super(3+) nanophosphors

• Published in: Journal of rare earths 2015-10, Vol.33 (10), p.1026-1030
• Main Authors: Lin, Lin, Lin, Hui, Wang, Zhezhe, Zheng, Biao, Chen, Jixing, Xu, Senyuan, Feng, Zhuohong, Zheng, Zhiqiang
• Format: Article
• Language: English
• Subjects: Alkali metals; Charge; Compensators; Defects; Emissions control; Luminescence; Nanostructure; Rare earth metals
• ISSN: 1002-0721
• DOI: 10.1016/S1002-0721(14)60521-4

A series of CaFCl:Tb super(3+) and CaFCl:Tb super(3+), A super(+) (A=Li, Na and K) nanophosphors were synthesized by the one-step sol-gel method, which were reported for the first time. The sample consisted of monodisperse particles, the average size of which was 37 nm. The emissions of Tb super(3+) ions and oxygen defects O sub(F)' were demonstrated in the CaFCl:Tb super(3+) samples. The former was made up of several peaks at 488, 545, 587 and 623 nm, ascribed to super(5)D sub(4) arrow right super(7)F sub(J)(J=6-3) transitions of Tb super(3+) ions. The latter was shown as a broad band peaked at about 450 nm. Alkali metal ions A super(+)(A=Li, Na and K) were introduced as the charge compensators to improve the luminescence of samples. The influence of charge compensators on the emissions of Tb super(3+) ions and oxygen defects O sub(F)' was investigated by the measurement of fluorescence spectra and luminescence decay curves. The results indicated that all the charge compensators weakened the defects emission. Furthermore, Li super(+) ion was the best charge compensator, because it not only reduced the defects emission but also increased the emission intensity of Tb super(3+) significantly. Our results suggested that this nanophosphor sensitized by the charge compensator might broaden potential applications of rare-earth doped CaFCl.