Exploring luminescence quenching mechanisms and temperature sensing capabilities of LiSrYW3O12:Sm3+ phosphors

Abstract

Optical thermometry has emerged as a crucial non-contact method for temperature measurement, serving a broad array of applications. This technique delivers precise readings without the need for physical contact, proving especially valuable in situations where traditional contact-based methods are impractical. However, the pursuit of heightened accuracy in optical thermometry remains an ongoing pursuit. Within this context, the advancement of luminescent thermometers assumes significant importance, offering the promise of enhanced temperature sensing capabilities. Through the exploration of novel materials and innovative strategies, the goal is to elevate the precision of these sensors, paving the way for more dependable temperature measurements in various environments. Therefore, the focus of the present study lies in the synthesis of a series of LiSrYW₃O₁₂ (LSYW):x%Sm³⁺ phosphors using the solid-state reaction technique, where x varies from 0.03 to 0.15. The investigation delves into the structures, morphologies, UV-Visible absorption, and luminescent characteristics of these phosphors. The down-conversion luminescence properties were studied under 405 nm laser excitation, leading to the determination of the optimal doping concentration at x = 0.05. Subsequent in-depth analysis focused on the optical temperature sensing properties, employing the fluorescence intensity ratio (FIR) method. The FIR of the ⁴F_3/2/⁴G_5/2 → ⁶H_7/2 transition consistently increased with temperature across the range of 300–583 K. The maximum relative sensitivities were determined as 1.58% K⁻¹ (at 301 K). These findings underscore the exceptional potential of LSYW doped with Sm³⁺ as a highly effective material for applications in high-temperature sensing. Through this research, the pursuit of more accurate and reliable temperature measurements takes a significant step forward, offering promising avenues for further exploration and utilization.