Optical Temperature-Sensing Performance of La 2 Ce 2 O 7 :Ho 3+ Yb 3+ Powders.

In this paper, La 2 Ce 2 O 7 powders co-activated by Ho 3+ and Yb 3+ were synthesized by a high temperature solid-state reaction. Both Ho 3+ and Yb 3+ substitute the La 3+ sites in the La 2 Ce 2 O 7 lattice, where the Ho 3+ concentration is 0.5 at.% and the Yb 3+ concentration varies in the range of 10~18% at.%. Pumped by a 980 nm laser, the up-conversion (UC) green emission peak at 547 nm and the red emission at 661 nm were detected. When the doping concentration of Ho 3+ and Yb 3+ are 0.5 at.% and 14% at.%, respectively, the UC emission reaches the strongest intensity. The temperature-sensing performance of La 2 Ce 2 O 7 :Ho 3+ with Yb 3+ was studied in the temperature range of 303-483 K, where the highest relative sensitivity (S r ) is 0.0129 K -1 at 483 K. The results show that the powder La 2 Ce 2 O 7 :Ho 3+ , Yb 3+ can be a potential candidate for remote temperature sensors.