Multiwavelength Responsive Luminescence for Temperature Sensing and Visualized Information Encoding/Decoding Based on Er³⁺/Tb³⁺-Doped Ba₂Ga₂GeO₇ Phosphors

Abstract

The rational exploration of lanthanide-doped phosphors is of great significance for realizing precise optical temperature sensing and information security applications. Here, triple-wavelength responsive Ba 2 Ga 2 GeO 7 :Er 3+ phosphors were synthesized by a solid-state method, and the samples gave highly pure green emissions under 808 and 382 nm excitations. Within the temperature range from 313 to 573 K, the corresponding temperature sensing performance based on the fluorescence intensity ratio was estimated, and the maximum relative sensing sensitivities were determined to be 0.97%, 1.20%, and 1.19% K −1 for the 980, 808, and 382 nm excitations, respectively, indicating the title materials are promising for use in temperature sensors. Furthermore, the introduction of Tb 3+ enables the materials to realize down conversion luminescence and long persistent luminescence, which greatly enrich the luminescence phenomena of the samples. Based on the abundant emission modes, novel information encryption strategies of digital displays and binary digital-ASCII multiplex codes are proposed, which provide reliable guidance on advanced visualized information encryption.

Swallowed Embedding of Nanopetal-Rich Microflowers in Flexible Photocatalytic and Thermoresponsive Functional Composite Fibers

“…In addition, Er 3+ filled in the 4 F 9/2 level caused by photon absorption and ET process are relaxed to the ground state, achieving the red emission at 656 nm. Therefore, the two-photon excitation process generated the green and red emissions of Er 3+ , and the intense green emissions centered at 528 and 550 nm can be used as thermal coupling energy levels for the application of temperature sensing. , …”

Excitation Mechanism Rearrangement in Yb3+-Introduced La2O2S:Er3+/Polyacrylonitrile Photon-Upconverted Nanofibers for Optical Temperature Sensors

“…With little difference between the thermal coupling levels, a state of thermal equilibrium could be reached between two energy levels with the help of phonons. The ratio of the luminescence intensity of 2 H 11/2 / 4 S 3/2 of Er 3+ ions following the Boltzmann distribution can be expressed as follows − FIR = I normalH I normalS = A 0.25em exp ( − Δ E KT ) + B where I H and I S denote the luminescence emission intensities of 2 H 11/2 → 4 I 15/2 and 4 S 3/2 → 4 I 15/2 , respectively. A and B are fitting coefficients.…”

Utilizing diametrically opposite thermal quenching luminescence to achieve highly sensitive temperature measurement and anti-counterfeiting

“…10–12 For example, Ge et al constructed a LIR thermometer with a maximum relative sensitivity of 1.2% K −1 by utilizing the TCLs of Er 3+ ( 2 H 11/2 and 4 S 3/2 ) in a Ba 2 Ga 2 GeO 7 host. 13 Luo et al developed a LIR thermometer based on the TCLs of Tm 3+ ( 1 G 4(2) and 1 G 4(1) ) in a Ca 2 YbF 7 host and the maximum relative sensitivity was 1.37% K −1 . 14 Unfortunately, the LIR thermometers based on the TCL type possess some inherent deficiencies.…”