Eu3+ doped Ca3LiZnV3O12 phosphors for four-mode optical thermometry

Abstract

Optical thermometer has brought about the widespread attention on account of non-contact and high-sensitive advantages. In this work, a novel optical thermometry with four modes was designed in Ca3LiZnV3O12:Eu3+ (CLZVO:Eu3+) phosphors. Benefitting from energy transfer of VO43− to Eu3+, CLZVO:Eu3+ phosphors (irradiated by 342 nm light) generate emissions from VO43− and Eu3+ simultaneously. As temperature increases, luminescent intensities of VO43− and Eu3+ show different downward trends, resulting in luminescent color changing with temperature. Besides, the excitation spectra of VO43− show a red shift with temperature boosting. Based on above luminescent characteristics, FI (fluorescence intensity), FIR (fluorescence intensity ratio), CIE (Commission Internationale de L'Eclairage) coordinate, and EIR (excitation intensity ratio) modes of CLZVO:Eu3+ thermometry were obtained. The maximum SR (relative sensitivity) values of each modes attain 2.56 %K−1 (340 K, FI), 2.18 %K−1 (320 K, FIR), 0.492 %K−1 (400 K, CIE coordinate), and 1.60 %K−1 (303 K, EIR). The minimal SR of FI and FIR modes are higher than 1.38 %K−1 and 1.08 %K−1 in 303–513 K temperature range. Above outstanding properties manifest the potentiality of CLZVO:Eu3+ for monitoring temperature.