Lanthanide Ion-Doped Bismuth Titanate Nanocomposites for Ratiometric Thermometry with Low Pump Power Density

Abstract

The sensing of temperature is closely related to human life. The noncontact ratio temperature measurement method has extensive applications in biochemical monitoring and industrial production. However, optical detection techniques based on fluorescence intensity ratio (FIR) still face many challenges, such as laser thermal effects, accuracy, and reversibility. In this article, the Yb3+/Er3+-codoped Bi4Ti3O12 nanocrystalline composite has been developed for thermometer. The introduction of Bi4Ti3O12 nanocrystals into the glass matrix exceptionally enhances the upconversion emission of Er3+ ions. The Yb3+/Er3+-codoped Bi4Ti3O12 nanocrystalline composite enables online temperature measurement under low power excitation density (0.75 W/cm2), which can reduce the thermal effect of the laser. In addition, Yb3+/Er3+-codoped nanocrystalline composite has excellent precision of temperature measurement in the temperature range of 293–573 K. The value of absolute sensitivity S a is 5.2 × 10–3. The maximum value of the relative error between the measured temperature and the actual temperature does not exceed 0.4% in the reliability test, and temperature measurement has excellent repeatability. Therefore, the developed Yb3+/Er3+-codoped nanocrystalline composite is a promising candidate for ratiometric thermometry.

Tailoring of Upconversion Emission in Tm3+/Yb3+-Codoped Y2Mo3O12 Submicron Particles Via Thermal Stimulation Engineering for Non-invasive Thermometry

“…Evidently, the FIR values are hardly changed even after several cycled heating-cooling processes. Moreover, to quantitatively describe the reversibility of the studied samples, we utilized the following expression to calculate the repeatability ( R ) , herein, Q i and Q avg stand for the obtained FIR value and the average FIR value, respectively. Thus, the R values of I 700 / I 481 and I 700 / I 654 combinations are 94.2 and 94.8%, respectively, indicating that the prepared compounds possess splendid reversibility.…”

Highly Sensitive Dual-Mode Optical Thermometry in Double-Perovskite Oxides via Pr3+/Dy3+ Energy Transfer

“…The S a‑max and S r‑max values are as high as 2.85 × 10 –4 s K –1 and 1.814% K –1 . In order to assess optical thermometer performance, the S a‑max and S r‑max of representative temperature sensing materials with FIR and Lifetime mode are displayed in Table . ,,,− The S a‑max and S r‑max of LMTO: Pr 3+ , Dy 3+ were the best among those of representative temperature sensing materials both in FIR and Lifetime mode, except for LaTiSbO 6 /YAG-PiG. However, LaTiSbO 6 /YAG-PiG system possessed the narrow valid temperature range (298–398 K).…”

Splendid four-mode optical thermometry design based on thermochromic Cs3GdGe3O9:Er3+ phosphors

“…Contactless luminescent thermometers mainly depend on temperature-responsive optical parameters 2,10,[18][19][20][21][22][23] such as emission intensity, luminescence peak position, spectral bandwidth, fluorescence decay lifetime (FL) and fluorescence intensity ratio (FIR). Thanks to its insensitivity to the measurement conditions and external interference, FIR, which depends on the thermally induced alteration of luminescence intensities of the two closely spaced thermally coupled levels (TECLs) or nonthermally coupled levels (NTECLs) of activators, 24,25 and FL, based on the temperature-dependent lifetimes, 26,27 are recognized as the most viable technologies for detecting temperature.…”