Color tunable luminescence and optical temperature sensing performance in a single-phased KBaGd(WO4)3:Dy3+, Eu3+ phosphor

Abstract

Abstract Herein, a series of Dy3+, Eu3+ single/co-doped KBaGd(WO4)3 phosphors (KBGW:Dy3+, Eu3+ for short) were prepared by solid-state reaction method and investigated by means of X-ray diffraction, SEM, photoluminescence excitation and emission spectra, decay curves and thermal quenching behavior. The KBGW:xDy3+ phosphors exhibited a weak blue emission around 480 nm and a strong yellow emission around 580 nm, corresponding to the characteristic 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 transitions of Dy3+ ions respectively. The decay curves of the KBGW:xDy3+ phosphors were analyzed in the framework of the Inokuti-Hirayama (IH) model and the concentration quenching mechanisms were determined to be dipole-dipole interactions. Under the excitation of 250 nm and 352 nm, both the characteristic emissions of Eu3+ and Dy3+ ions were observed in the KBGW:Dy3+, Eu3+ phosphors. Furthermore, with the increasing concentration of Eu3+, color-tunable emissions from yellow to red were obtained in these samples. Based on the thermal quenching behavior, the optical sensitivity of the sample to temperatures, including absolute sensitivity (Sa) and relative sensitivity (Sr), were calculated and evaluated for the application in optical thermometry.