3+ (Er 3+, Tm 3+ and Ho 3+)-doped NaYb(MoO 4) 2 upconversion phosphors as wide range temperature sensors with high sensitivity]]>

摘要

AbstractWell-crystallized NaYb(MoO4)2doped with lanthanide ions (Ln3+: Er3+, Tm3+and Ho3+) are successfully synthesized by hydrothermal method with further calcination. And the samples with different morphologies are obtained by changing the pH values and the molar ratio of Ln(NO3)3/Na2MoO4of the resultant solutions. The upconversion (UC) luminescence spectra of NaYb(MoO4)2: Ln3+between 323?K and 573?K under 980?nm excitation exhibit temperature-dependent property. The fluorescence intensity ratio (FIR) techniques with thermally coupled states (TCS) (Er3+:2H11/2,4S3/2?→?4I15/2, Tm3+:1G4(1),(2)?→?3H6, Ho3+:5F5(1),(2)?→?5I8) have high sensitivity (S) values (Er3+: 0.0122?K?1?at 548?K, Tm3+: 0.0025?K?1?at 323?K and Ho3+: 0.00035?K?1?at 323?K). The non-TCS (Ho3+:5F5,5S2/5F4?→?5I8) is used to extend the range of S, and the slope of FIR (non-TCS)-T is the S value as high as 0.02455?K-1in the wide temperature range from 323?K to 573?K.Graphical abstractDisplay OmittedHighlights?Er3+/Tm3+/Ho3+doped NaYb(MoO4)2phosphors show strong visible luminescence.?FIR technique of thermally coupled states (TCS) and non-TCS have been explained.?The temperature sensor has high sensitivity in wide range (323–573?K).