Exceptional low-temperature fluorescence sensing properties in novel KBaY(MoO):Yb,Ho materials based on FIR of Ho transitions F → I/S → I

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2022-05, Vol.1 (17), p.663-661
• Main Authors: Li, Kai, Zhu, Daiman, Yue, Changtao
• Format: Article
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d2tc01061e

In this report, a series of novel KBaY(MoO 4 ) 3 :Yb 3+ ,Ho 3+ (KBYMO:Yb 3+ ,Ho 3+ ) materials with intense up-conversion (UC) luminescence properties were synthesized using a high-temperature solid-state reaction method. Upon 975 nm near infrared (NIR) laser excitation, KBYMO:Yb 3+ ,Ho 3+ mainly showed two emission bands at around 544 and 658 nm, as well as a feeble one at around 755 nm, corresponding to Ho 3+ 5 F 4 , 5 S 2 → 5 I 8 , 5 F 5 → 5 I 8 and 5 F 4 , 5 S 2 → 5 I 7 transitions, respectively. The UC luminescence mechanism in this kind of material was determined to be a two-photon process, including simultaneous energy transfer from Yb 3+ to Ho 3+ . In order to explore its potential applications in low-temperature fluorescent thermometers, the temperature-dependent behavior (53-293 K) of KBYMO:0.60Yb 3+ ,0.01Ho 3+ as a representative was investigated in detail. Based on fluorescence intensity ratio (FIR) technology, the calculated FIR values of I 640/550 ( 5 F 5(1) → 5 I 8 / 5 S 2 → 5 I 8 ) in KBYMO:0.60Yb 3+ ,0.01Ho 3+ (53-293 K) were adopted as the original data, which have been rarely used in previous systems. Therefore, the optimal absolute sensitivity S a and relative sensitivity S r were determined to be 0.0186 K −1 (233 K) and 31.45% K −1 (53 K), respectively, showing its potential as a key component material in low-temperature fluorescent thermometers. The fluorescent low-temperature sensing ability of a novel kind of KBaY(MoO 4 ) 3 :Yb 3+ ,Ho 3+ material has been evaluated in this work.