Luminescence properties of KBaYSi2O7:Ce/Eu-Tb phosphors for multifunctional applications

In this work, the multifunctional KBaYSi2O7:Ce/Eu-Tb (KBYS:Ce/Eu-Tb) phosphors were synthesized by using the conventional high-temperature solid-state reaction, and the luminescence properties were investigated for LED and optical thermometer applications. The single-phase samples were checked by x-ray diffractometer patterns. The energy transfer was found in both Eu (2+)-Tb3+ and Ce3+-Tb3+ codoped samples, which was verified by spectra and decay curves. Correspondingly, the tunable emission was realized by adjusting the dopant concentrations and white light was obtained in the KBYS:4%Eu2+, 9%Tb3+ sample, owing to the energy transfers among Eu2+, Tb3+, and Eu3+. By studying the temperature dependence of the KBYS:2%Ce3+, 7%Tb3+, it has been found that the fluorescence intensity ratio for Tb3+ and Ce3+ emissions changes with temperature, indicating the potential application in an optical thermometer. The high absolute sensitivity was determined to be 0.012 K-1. By evaluating the thermal quenching luminescence of the KBYS:4%Eu2+, 9%Tb3+, the thermal quenching temperature T-0.5 was determined to be 555 K, implying high thermally luminescent stability. (C) 2019 Optical Society of America