Effects of Tm³⁺ concentration on upconversion luminescence and temperature‐sensing behavior in Tm³⁺/Yb³⁺:Y₂O₃ nanocrystals

Abstract

The effects of Tm 3+ concentration on upconversion emission and temperaturesensing behavior of Tm 3+ /Yb 3+ :Y 2 O 3 nanocrystals were investigated. Blue and red emissions were observed under 980 nm excitation. Both upconversion emissions and the blue to red intensity ratio were found to decrease with increasing Tm 3+ concentration. The temperature-sensing performances of the samples were studied, the fluorescence intensity ratio of 1 G 4(a) → 3 H 6 (477 nm) and 1 G 4(b) → 3 H 6 (490 nm) transitions from Tm 3+ ions was chosen as the thermometric index. The results showed that the sensor sensitivity was sensitive to Tm 3+ ion concentration. The maximum sensitivity of~32 × 10 −4 K −1 was obtained for 0.1%Tm 3+ /5%Yb 3+ :Y 2 O 3 nanocrystals at 344 K. Moreover, a marked optical induced heating effect was also found in the nanocrystals. The prepared Tm 3+ /Yb 3+ :Y 2 O 3 nanocrystals could be used in temperature-sensing probes and in optical heaters.

Luminescence Temperature Sensing and First Principles Calculation of Photoelectric Properties in C12A7 Co-Doped Eu3+ Ions

“…Eu 3+ ions show lattice vibration and symmetry, and the lengths of the ligand–Eu 3+ band make Eu 3+ ions good candidates for a temperature probe. However, luminescence emission can be influenced by the host lattice. , Recent studies of thermal effects have focused on oxide hosts due to their high chemical and physical stability. − The 12CaO·7Al 2 O 3 (C12A7) oxide has a cage structure, which had good insulation performance, wide optical absorption band gap, and good optical transparency. One cage structure is connected with eight adjacent ones in a three-dimensional space, which promotes the optical stability of C12A7. , The C12A7 crystal due to its close arrangement structure had excellent chemical stability and thermal stability, which realized the precise detection of temperature.…”

“… 15 , 16 Recent studies of thermal effects have focused on oxide hosts due to their high chemical and physical stability. 17 − 22 The 12CaO·7Al 2 O 3 (C12A7) oxide has a cage structure, which had good insulation performance, wide optical absorption band gap, and good optical transparency. One cage structure is connected with eight adjacent ones in a three-dimensional space, which promotes the optical stability of C12A7.…”

Nano-Crystallization of Ln-Fluoride Crystals in Glass-Ceramics via Inducing of Yb3+ for Efficient Near-Infrared Upconversion Luminescence of Tm3+

“…Thus, Yb 3+ -Tm 3+ co-doped materials were more efficient candidates for NIR-to-NIR UC luminescence and were significant light sources for biologically non-destructive detection. In the past decades, a large number of investigations about Yb 3+ -Tm 3+ co-doped UC materials have been widely reported for achieving high-efficiency NIR UC luminescence [ 14 , 15 , 16 , 17 , 18 , 19 , 20 ].…”

Improved relative temperature sensitivity of over 10% K−1 in fluoride nanocrystals via engineering the interfacial layer

“…11,12 Lanthanide-doped fluoride upconversion (UC) nanocrystals (NCs) have been widely studied in the fields of bio-imaging 13 and bio-sensing 14 owing to their low toxicity, 15 bio-compatibility 16 and weak background fluorescence. 17 Moreover, lanthanide activators with thermally coupled level (TCL) pairs, such as Er 3+ : 2 H 11/2 and 4 S 3/2 as well as Tm 3+ : 3 F 2,3 and 3 H 4 18,19 have been broadly employed for temperature sensing. From this view point, lanthanide-doped fluoride UCNCs are much appropriate for the monitoring of temperature in bio-systems.…”