YVO₄ Nanoparticles Doped with Eu³⁺ and Nd³⁺ for Optical Nanothermometry

Abstract

The ongoing research in biology, medicine, and technology requires accurate measurement and control of temperature at micro and nanoscales. Rare-earth-doped luminescence nanoparticles were found to be one of the most perspective systems for noncontact ratiometric temperature sensing for various applications. Despite plenty of single-doped sensors with thermally coupled levels, the development of a dual-center thermometer with enhanced thermometric performances is still challenging. Here, we demonstrate two approaches to construct ratiometric luminescence YVO 4 :Eu 3+ /Nd 3+ nanothermometers: co-doping and mixture of single-doped nanoparticles. The rational choice of doping concentration could significantly improve thermometric characteristics. An increase in doping concentration did not affect thermal sensitivity, while temperature resolution was improved. Co-doped and mixed nanoparticles displayed similar thermal sensitivity (∼0.8% K −1 ), whereas the temperature resolution of mixed sensors (0.4−1.0 K) was found to be several times better compared to the co-doped ones (1.1−3.0 K). The obtained results provide a strategy for developing promising dual-center luminescence thermometers with submicron spatial and subdegree thermal resolution.

Vibrationally Induced Photophysical Response of Sr2NaMg2V3O12:Eu3+ for Dual‐Mode Temperature Sensing and Safety Signs

“…At the same time, the almost constant decay time of Eu 3þ implies that a pronounced To provide a more detailed analysis, the radiative and nonradiative decay rates at various temperatures were calculated using 4f-4f intensity theory. [57][58][59][60][61][62][63][64][65] The total radiative decay rate (A R ) is estimated by taking the sum of radiative rates A 0J for each 5 D 0 -7 F J transition given by…”

Upconverting NIR-to-NIR LuVO4:Nd3+/Yb3+ Nanophosphors for High-Sensitivity Optical Thermometry

“…The increase of the Yb 3+ doping concentration resulted in the significant enhancement of Yb 3+ luminescence band intensity (>850 nm) for mixed samples, while Yb 3+ emission almost did not change for codoped samples. Noteworthily, contrary to YVO 4 :Eu 3+ /Nd 3+ nanothermometers, mixed thermal sensors display much worse thermal performances compared to codoped ones. , In addition to relative sensitivity, we calculated absolute thermal sensitivity, S a , which displayed an absolute LIR change with temperature variation ( S a = dLIR/d T ). Figure S6 presents the temperature evolution of S a of codoped and mixed LuVO 4 :Nd 3+ /Yb 3+ phosphors.…”

Thermochromic Upconversion Emission in Tm3+/Yb3+-Codoped La2Mo3O12 Microparticles via Negative Thermal Expansion Engineering for Ultrahigh Sensitivity Optical Thermometry

“…Compared with the conventional contacted thermometers, a lot of attention has been attracted by luminescence thermometers, which utilize temperature-associated fluorescence characteristics, such as fluorescence intensity ratio (FIR), band position, decay time, full width at half-maximum of emission band, etc., − of luminescent materials because of their advantages of rapid response, high accuracy/resolution, and contactless characteristic. , Particularly, by adopting the FIR technique, optical thermometry is extensively adopted, in which the temperature-related emission intensities of thermally coupled levels (TCLs) of rare-earth ions are investigated. , Fu et al revealed that the thermometric properties of rare-earth ions, which were based on their TCLs, can be adjusted by controlling the excitation wavelength and utilizing tridoping engineering. , However, the optical thermometers based on the TCLs of rare-earth ions possess low relative sensitivity ( S r ) triggered by the small energy band gap of TCLs (200 ≤ Δ E ≤ 2000 cm –1 ). , For the purpose of addressing this issue, researchers proposed a new route, namely, using the FIR technique to deal with the temperature-dependent emission intensities of non-TCLs of luminescent compounds. To date, some compounds, such as BaTiO 3 :Er 3+ /Ho 3+ /Yb 3+ , La 3 Li 3 W 2 O 12 :Eu 3+ /Mn 4+ , Na 5 Y 9 F 32 :Ce 3+ /Tb 3+ , YVO 4 :Eu 3+ /Nd 3+ , LaGaO 3 :Cr 3+ /Nd 3+ , and Ca 14 Al 10 Zn 6 O 35 :Ti 4+ /Eu 3+ , − with good thermometric properties, in which the non-TCLs are used, have been developed to realize contactless temperature sensing. Thereby, the utilization of the temperature-dependent FIR value of non-TCLs is a facile strategy to manipulate the thermometric behaviors of luminescent materials.…”