Luminescence mining via energy transfer upconversion and anti-Stokes emission in Er, Yb: LiYF4: Thermometry and NIR detection applications

Background The research on luminescence thermometry is mobilizing rapidly due to its advantages. Especially rare-earth-doped phosphors attract more attention with their efficiency in luminescence. Yb/Er co-doped LiYF4 has strong ability in luminescence, and owing to its distinct material properties, it is studied for thermometry as well as radiation detection. The advantages of optical thermometry are realized for precise temperature measurements where conventional techniques fail. In addition, near-infrared detection has gained importance to avoid eye accidents. Method An eco-friendly and self-propagating microwave-assisted combustion route was adapted to prepare micro-phosphors. The luminescence performance of this phosphor was studied by varying concentration and temperature. Significant Findings Prepared phosphor exhibited both upconversion and anti-Stokes phenomena. The upconversion luminescence was immensely enhanced at a cryogenic temperature compared with room temperature. The fluorescence intensity modes of non-identical ions have unleashed the highest relative sensitivity of 1.19 and 2.48 %K−1, respectively. Interestingly, ever-greater absolute sensitivity of 2.406 K−1 was produced by this phosphor through the fluorescence intensity ratio. A simple, hand-held device has been developed to detect near-infrared radiation. The luminescence properties of LiYF4: Yb/Er phosphor exhibited its ingenuity in the precise sensing of near-infrared radiation and temperature.