Tuning of the up-conversion emission and sensitivity of luminescent thermometer in LiLaP4O12:Tm,Yb nanocrystals via Eu3+ dopants.

Up-converting properties of LiLaP 4 O 12 :1%Tm 3+ , 50%Yb 3+ , x% Eu 3+ nanocrystals were investigated upon 975 nm excitation. It was shown that their emission color can be tuned from blue to orange via changing Eu 3+ concentration from 10% to 49%. The potential suitability of these nano-phosphors for non-contact temperature sensing was investigated. Thermal changes of luminescence intensity ratio of 1 D 2 → 3 F 4 and 1 G 4 → 3 F 4 emission bands of Tm 3+ ions were strongly affected by Eu 3+ concentration owing to increasing efficiency of distance-dependent Tm 3+ →Eu 3+ energy transfer. The sensitivity of such luminescence thermometer was varying from 0.1%/°C to 1.9%/°C in response to varying Eu 3+ concentration from 49 down to 10%. [ABSTRACT FROM AUTHOR]