Deciphering crystal structure and photophysical response of Bi3+ and Pr3+ co-doped Li3Gd3Te2O12 for lighting and ratiometric temperature sensing

Crystal structure and photophysical response of Bi3+ and Pr3+ co-doped Li3Gd3Te2O12 system was investigated for lighting and ratiometric temperature sensing applications. The double substitution at the dodecahedral site was confirmed via Rietveld refinement and Raman spectra analysis. Considering the full advantage of distinct and characteristic cyan and orange emissions of Bi3+ and Pr3+, the emission tunability towards white region was achieved by the proposed co-doping combination. The as-prepared Li3Gd3Te2O12: Bi3+, Pr3+ phosphor exhibited characteristic and enhanced emission of Pr3+ under the excitation of 297 nm. The activation energy of 0.29 eV was obtained for the co-doped matrix, exhibiting better thermal stability. Further, the temperature sensing properties were evaluated based on the temperature dependent photoluminescence emission and decay curves in the range 100-300 K. Notably, the as-prepared Li3Gd3Te2O12: Bi3+, Pr3+ phosphor showed a maximum relative sensitivity of 0.672% K-1, as based on decay curve method, indicating that the phosphor can act as a potential candidate for optical temperature sensing in the physiological range. These findings demonstrate the efficiency of new co-doping combination Bi3+-Pr3+ for designing multifunctional phosphors. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The crystal structure and photophysical response of Bi3+ and Pr3+ co-doped Li3Gd3Te2O12 system were investigated for lighting and ratiometric temperature sensing applications. The co-doped matrix exhibited enhanced emission of Pr3+ and better thermal stability with an activation energy of 0.29 eV. The maximum relative sensitivity of 0.672% K-1 was achieved for optical temperature sensing, indicating the efficiency of the new co-doping combination Bi3+-Pr3+ for designing multifunctional phosphors.