Temperature sensing behavior of Tm3+: 1G4(a), 1G4(b) in oxyfluoride glass ceramics containing BaYbxY(1-x)F5 nanocrystals

Tm3+ doped transparent oxyfluoride glass ceramics containing BaYbxY((1-x))F-5 nanocrystals were prepared via high temperature solid phase melting method, of which up-conversion emission is achieved by the Yb3+-mediated energy transfer process. The required photon number of Tm3+ ions emissions in BaYbxY((1-x))F-5 nanocrystals was calculated through the luminescence spectra, revealing the strong dependence of energy transfer mechanism on Yb3+ ions concentration. Meanwhile, based on the fluorescence intensity ratio technology, the effect of different energy transfer mechanism on the temperature sensitivity was investigated by the temperature-dependent luminescence intensity of thermally coupled energy levels of Tm3+:(1)G(4)(a), (1)G(4)(b). The obtained sensitivity decreases with the increase of Yb3+ ions content, which is mainly attributed to the changes in photon absorption process of Tm3+ : (1)G(4)(b). (C) 2020 Published by Elsevier B.V. on behalf of Chinese Society of Rare Earths.