Temperature sensing of Sr 3 Y 2 Ge 3 O 12 :Bi 3+ ,Sm 3+ garnet phosphors with tunable sensitivity.

In this study, a novel temperature-sensitive material, Sr 3 Y 2 Ge 3 O 12 :Bi 3+ ,Sm 3+ phosphor, was successfully synthesized by a solid-state reaction method. Under 376 nm light excitation, the as-prepared phosphor presents both blue emissions of Bi 3+ and orange red emissions of Sm 3+ due to energy transfer from Bi 3+ to Sm 3+ . Owing to the significant difference in thermal quenching properties and the distinguishable emission between Bi 3+ and Sm 3+ ions, the temperature sensing performance of the prepared phosphor was evaluated by measuring the fluorescence intensity ratio (FIR) of Sm 3+ versus Bi 3+ . More importantly, for the first time, it was found that the absolute and relative sensitivities of Sr 3 Y 2 Ge 3 O 12 :Bi 3+ ,Sm 3+ could be tuned by changing the concentration of activators to determine the optimal temperature measurement conditions, which opened up the possibility of improving the performance of fluorescence temperature sensing materials.