Upconversion luminescence of NaYF4: Yb3+, Er3+ for temperature sensing

Optical Temperature Sensor Based on Infrared Excited Green Upconversion Emission in Hexagonal Phase NaLuF4:Yb3+/Er3+ Nanorods

“…The sensitivity of NaLuF 4 :20%Yb 3+ /1.5%Er 3+ nanorods is noted to be 0.0036 K −1 at 293 K and 0.0044 K −1 at 343 K. It can be seen that the sensitivity kept increasing in our experimental temperature range and the maximum sensitivity theoretically is 0.0056 K −1 at 523 K. The sensitivity of NaLuF 4 :20%Yb 3+ /1.5%Er 3+ nanorods is 0.0044 K −1 at 343 K. It is superior to 20 and 0.0032 K −1 for Yb 3+ /Er 3+ codoped NaYF 4 nanocrystals. 6 It is also worthwhile to compare our results with other similar studies. The excitation power density of 4.2 W/cm 2 (33 mW) used by our group is much less than that of 2.0 × 10 3 W/cm 2 and ∼60 W/cm 2 (500 mW) applied in Refs.…”

“…The lower excitation power density is favorable to improve the sensitivity, due to the reduction of the laser heating effect. 6 Erbium (the activator) and ytterbium (the sensitizer) codoped hexagonal phase NaYF 4 represents the material with the highest upconversion efficiency reported so far. 7 8 Additionally, such material with nano-sized exhibits low * Authors to whom correspondence should be addressed.…”

Hydrothermal synthesis and up-conversion luminescence properties of NaYF4:Yb3+,Tm3+ phosphors

“…Yb 3þ ion is the most efficient and widely used sensitizer for the up-conversion phosphors based on Tm 3þ , because of its strong absorption at 980 nm [24]. To carefully study the influence of the Yb 3þ ions content on luminescence property, the Yb 3þ ion values were taken as 22, 24, 26, 28, and 39%, respectively, keeping other reaction conditions constant (sodium tartrate/RE ¼ 0.5, Tm 3þ ions content of 0.4%, NH 4 F/RE ¼ 8, hydrothermal time of 4 h and hydrothermal temperature of 180 C).…”

Optical investigation in shuttle like BaMoO4:Er3+–Yb3+ phosphor in display and temperature sensing

“…Therefore, FIR method can improve the sensor sensitivity by minimizing fluorescence loss, fluctuations of exciting light and electromagnetic compatibility problem, etc. [22]. Hao et al [23] have reported that change in FIR between two close emission bands can be useful in temperature mapping of a single living cell.…”