Up-conversion La4GeO8:Er3+,Yb3+ optical thermometer based on fluorescence intensity ratio technique

We synthesized up-conversion (UC) La4GeO8:Er3+,Yb3+ phosphors, and further investigated their crystal struc-tures, luminescent properties and optical temperature sensing behaviors according to fluorescence intensity ratio (FIR). Excited by 980 nm laser, all samples exhibit 526, 546 and 656 nm emission bands, which are derived from the characteristic transitions of Er3+. More importantly, samples show outstanding temperature sensing be-haviors. FIR thermometer has the highest relative sensitivity of 1.293 %K-1 (313 K) and the best temperature resolution is 0.03 K (313 K). All the results above reveal that La4GeO8:Er3+,Yb3+ phosphor might be a good alternative for optical temperature sensing.

Automated summary

In this study, we synthesized up-conversion La4GeO8:Er3+,Yb3+ phosphors and investigated their crystal structures, luminescent properties, and optical temperature sensing behaviors. The results showed that the phosphors exhibited temperature sensitivity and demonstrated excellent temperature sensing performance.