Multiple ratiometric thermometry: Enhanced sensing behaviour via Stark sublevels

Frequency upconversion based thermally stable molybdate phosphors in a temperature sensing probe

“…Rare-earth doped inorganic phosphors have potential in various applications such as NIR to visible upconverters, displays, anticounterfeiting, solar cells, optical sensing, etc. [1][2][3][4][5][6][7][8] The halide and sulfide-based hosts are often considered efficient upconverting materials because of their low phonon frequencies. Still, they are limited in various applications due to their hygroscopic & toxic nature.…”

“…21,23 While monitoring the thermal behavior of Er 3+ -Yb 3+ :MgMoO 4 phosphors, Mondal and Rai found that the Stark sublevels can deliberately enhance the sensitivity and temperature uncertainty of the phosphors. 3 In another report, Liu et al proposed the ratiometric thermometry of the Er 3+ -Yb 3+codoped NaGd(WO 4 ) 2 phosphors using Stark sublevels of the green emission under 980 nm excitation. 8 This paper synthesized Er 3+ -Yb 3+ :NaGd(MoO 4 ) 2 phosphors using the solid-state reaction route.…”

A dual-ratiometric optical thermometry based on Sr2LaF7:Er3+ crystal-implanted pliable fibers

“…10(f), it can be found that different excitation powers have a limited effect on the FIR value and sensitivity of main sensing in the SLF-E 8 /PAN composite fibers. The temperature resolution δT is an important parameter for optical temperature sensing and indicates the smallest temperature variation sensed by an optical sensor, 46 which can be defined as:where δ FIR represent the standard deviation of FIR. The values of temperature resolution δT are shown in Fig.…”

“…Sr 2 LaF 7 nanocrystals (SLF-E NCs), as a cubic phase optical medium with infinitesimal nanosize and excellent dispersibility, can produce a smaller composite fiber which is beneficial for applications at nano-scale and in a harsh environment. [41][42][43][44][45][46][47][48][49][50] With the introduction of Er 3+ ions into crystals Sr 2 (La 1−x Er x )F 7 , composite fibers show both the pliability of fibers and the temperature transfer properties of Er 3+ ions, which provide the possibility of optical temperature sensing in microregions. [51][52][53][54][55][56][57][58][59][60][61][62] In this work, dual-feedback optical thermometry with a single emitter based on Sr 2 (La 1−x Er x )F 7 /polyacrylonitrile composite fibers (SLF-E/PAN) is reported.…”

Ratiometric upconversion luminescence nanoprobes from construction to sensing, imaging, and phototherapeutics

“…As summarized in Table 1, previous studies have largely reported various types of ratiometric UCL nanoprobes for temperature sensing. [168][169][170][171][172][173][174][175][176]193,194 Most of the nanoprobe systems consist of lanthanide-doped UCNPs, other upconverting luminescent inorganic materials, 29,36,40,43,45,47,48,54,[56][57][58][59][60][61]65,[73][74][75][76] and the derivatives with functional modifications, including the core@shell, 37,38,41,68,72,78,79 hollow/porous, 38 complexes, 46,49,51 hybrid, 32,52 mixture, 33,35 assembly, 34,55 or engineering structures.…”