Photoluminescence properties and temperature sensing of Pr3+-Doped Li3Ba2Gd3(WO4)8 quaternary tungstate

Abstract

Tungstates, as an important class of hosts, have attracted widespread research interest in various optical fields, such as lighting, lasing, and luminescence thermometry. Herein, we propose novel Pr³⁺-doped Li₃Ba₂Gd₃(WO₄)₈ (Pr³⁺:LBGW) phosphors and discuss the associated temperature-sensing performance in detail. The structural characterization and composition analysis indicate the high crystalline quality of as-prepared Pr³⁺:LBGW phosphors. The following photoluminescence investigations systemically study the influences of Pr³⁺-doped concentration and excitation wavelength. Apart from the obvious ³P₀ → ³H₄, ³F₂ transitions of Pr³⁺ ions, there is also a broad host emission band with a full width at half maximum (FWHM) of 0.54 eV. The fluorescence thermometry based on the temperature-dependent Pr³⁺ and host emissions exhibits outstanding temperature-sensing capability. The maximum relative sensitivity is located in the physiological temperature range with a value of 1.72 %·K⁻¹ at 300 K, comparable to those Pr³⁺-doped tungstate luminescent thermometers. Our work highlights the versatility of Pr³⁺-doped tungstate materials in developing new-type luminescent materials, especially for temperature-sensing candidates.