Targeted high-precision up-converting thermometer platform over multiple temperature zones with Er³⁺

Abstract

Ratio-metric luminescence thermometer based on trivalent erbium ions is a noninvasive remote sensing technique with high spatial and temporal resolution. The thermal coupling between two adjacent energy levels follows the...

Revealing the role of a unique local structure in lanthanide-doped Cs2LiInCl6 in boosting visible and NIR-II luminescence

“…1a, the unique local structure of Cs 2 LiInCl 6 DP has two points: one is the trigonal-phase crystallographic structure compared with the cubic-phase structure of Cs 2 NaInCl 6 , and the second is that Cs 2 LiInCl 6 has two independent In 3+ active sites (In1 and In2) with a lower site symmetry of D 3d , whereas Cs 2 NaInCl 6 has only one In 3+ active site with the highest site symmetry of O h . 6 The distances of In1–In1 (or In2–In2) and In1–In2 are 7.3184 and 7.3712 Å, respectively, confirming that the two In sites are not crystallographically equivalent. The difference could allow us to thoroughly understand the mechanism underlying the local-structure-dependent PL properties.…”

“…2a. Comparing with Cs 2 NaInCl 6 DP, 6,10 the lowest frequency mode (∼174 cm −1 ) of pure Cs 2 LiInCl 6 belongs to the E g mode, due to the asymmetric stretching of In–Cl bonds in the octahedral cages, and the other two frequency modes of 289 and 321 cm −1 can be attributed to the A 1g mode related to the octahedrons. After Yb/Er co-doping, both A 1g and E g modes were slightly shifted to longer wavenumbers due to the sublattice distortion of the octahedrons.…”

“…Lead-free halide double perovskites (DPs) as promising luminescent materials have received increased interest from researchers for potential applications in various materials science and biomedical fields owing to their low toxicity and high chemical-, thermal-, and photo-stability. [1][2][3][4][5][6][7][8] However, the photoluminescence (PL) performance is very poor for most DPs in view of the indirect bandgaps or parity-forbidden transitions, limiting their further practical photonic and biological applications. Fortunately, DPs have the general formula A 2 M + M 3+ X 6 (where A = Rb + and Cs + ; M + = Ag + and Na + ; M 3+ = In 3+ and Bi 3+ ; and X = Cl − and Br − ) that provides abundant opportunities for the material composition adjustment.…”

Convolutional neural networks driving thermally enhanced upconversion luminescence for temperature sensing: achieving high accuracy and robustness across a wide temperature range

“…65 The above physical processes involved in the TCLs would make the LIR 1 value deviate from the prediction of the theoretical pattern, consequently resulting in a large measurement error. 66 Similar to the case of LIR 1 , luminescence thermometry based on LIR 2 also suffers from the inconsistency between the calibration curve and the ratio used for calibration. In contrast, 1D In practical application, the random background light, which can seriously distort the shape of the spectrum, represents a major interference with regard to the luminescence thermometry.…”

Manipulating the thermometric behaviors of Er3+/Yb3+/Ho3+-tridoped La2Mo3O12 polychromatic upconverting microparticles via adjusting spatial mode and a sensing strategy

“…Traditional thermometers, which take the advantages of the law of thermodynamics, provide a direct measurement but they cannot be employed in some special situations, such as micro-sized objects, power stations, intracellular liquids, etc. 1,2 In comparison, non-contact optical thermometers based on luminescent materials have received lots of attention because of their fast response, high accuracy, real time monitoring and high spatial resolution. 3,4 Generally, the fluorescence intensity ratio (FIR) technique is widely used to realize temperature monitoring.…”