Optical temperature sensing properties of Er3+/Yb3+ co-doped LuVO4 up-conversion phosphors

Abstract

In this paper, Er3+/Yb3+ co-doped LuVO4 phosphors were synthesized by the hydrothermal method. The crystalline structure and up-conversion luminescence features have been investigated by X-ray diffraction (XRD), Raman spectroscopy and up-conversion emission spectra. Green emission located at 525 nm (2H11/2 → 4I15/2) and 554 nm (4S3/2 → 4I15/2), red emission centered at 655 nm (4F9/2 → 4I15/2) have been observed excited by 980 nm laser. The up-conversion luminescence is enhanced significantly with the co-doping of Yb3+ ions due to the effective energy transfer from Yb3+ to Er3+ ions. Moreover, the optical temperature sensing property are recorded based on two thermally coupled levels (2H11/2 and 4S3/2) in the range of 100–500 K. By using the fluorescence intensity ratio method, the maximum value of absolute sensitivity (SA) is obtained to be 0.0067 K−1 at 500 K. The results indicate that the LuVO4:Er3+/Yb3+ phosphors with high sensitivity could be applied as potential optical temperature-sensing materials.