Three-mode optical thermometer based on Ca3LiMgV3O12:Sm3+ phosphors

A series of Ca3-xLiMgV3O12:xSm(3+) (CLMV:Sm3+) phosphors were elaborated to provide new optical temperature sensing materials. Their structures, morphologies, and luminescent properties were comprehensively explored. The energy transfer from VO(4)(3-)to Sm(3+ )was illustrated using luminescent spectra and luminescent decay curves. The different temperature dependent emission and excitation characters of VO(4)(3-)group and 4f-4f transition of Sm(3+ )were used to design a three-mode optical temperature sensor. Temperature dependent fluorescence in-tensity ratio (FIR) value of I(Sm3+) and I(VO43-), Commission International de L'Eclairage (CIE) coordinate, and excitation intensity ratio (EIR) value of I-383nm/I-405nm in excitation spectra are the three sensing modes. The maximum value of absolute sensitivity (S-A) and relative sensitivity (S-R) in FIR mode are 9.11 %K(-1 )at 513 K and 1.99 %K-1 at 357 K, respectively. And S(R )is bigger than 1.21 %K-1 between 303 and 513 K, which is superior to that of thermometry based on Er3+ doped upconversion phosphors. The maximum SR in EIR mode is 1.39 %K(-1 )at 393 K. Our results indicate that CLMV:Sm3+ phosphors might have potential application as optical thermometry with self-reference character.

Automated summary

A series of CLMV:Sm3+ phosphors were synthesized as new optical temperature sensing materials, and their structures, morphologies, and luminescent properties were investigated. The energy transfer from VO(4)(3-)to Sm(3+) was demonstrated, and a three-mode optical temperature sensor was designed based on the temperature dependent emission and excitation characteristics of VO(4)(3-) and Sm(3+). The sensing modes included the fluorescence intensity ratio (FIR) of I(Sm3+) and I(VO43-), Commission International de L'Eclairage (CIE) coordinate, and the excitation intensity ratio (EIR) of I-383nm/I-405nm. The CLMV:Sm3+ phosphors showed high absolute and relative sensitivities in FIR and EIR modes, indicating their potential as self-referencing optical thermometers.