Temperature-induced phase transition and temperature sensing behavior in Yb3+ sensitized Er3+ doped YPO4 phosphors

YPO4:Er3+, Yb3+ microcrystals have been manufactured using hydrothermal synthesis and annealed at different temperature for 3 h. With the increases of calcination temperature, the phase transformation of yttrium phosphate from hexagonal to tetragonal phase is reported base on the representation of X-ray diffraction (XRD). Besides, the size and morphology of yttrium phosphate have been clearly observed by employing field-emission scanning electron microscopy (FE-SEM). By selective annealing temperature and doped concentration procedure, YPO4:1%Er3+, 15%Yb3+ phosphors that annealed at 1000 degrees C for 3 h after hydrothermal synthesis show the strongest luminescence intensity under a 980 nm laser diode excitation. The temperature sensing behavior of YPO4:1%Er3+, 15%Yb3+ phosphors has also been investigated in detail. The result indicated that YPO4:1%Er3+, 15%Yb3+ phosphors could be considered as potential materials for optical temperature sensors. (C) 2016 Elsevier B.V. All rights reserved.