Dual-emission center ratiometric optical thermometer based on Bi and Mn co-doped SrGdAlO phosphor

In recent years, more and more attention has been paid to optical temperature sensing, and how to improve its accuracy is the most important issue. Herein, a new temperature sensing material, SrGd 2 Al 2 O 7 :Bi 3+ ,Mn 4+ , based on fluorescence intensity ratio was designed in this work. It has both blue-purple and red luminescence under 300 nm excitation, and the dual-emitting centers with distinct colors, the different thermal sensitivities of Bi 3+ and Mn 4+ , and the energy transfer between Bi 3+ and Mn 4+ give it excellent signal resolution and accurate temperature detection. The S a of SrGd 2 Al 2 O 7 :0.04Bi 3+ ,0.003Mn 4+ phosphor reaches a maximum value of 8.573% K −1 at 473 K, and the corresponding S r is 1.927% K −1 , both of which are significantly better than those of most other reported optical temperature sensing materials. Taking all the results into account, the SrGd 2 Al 2 O 7 :0.04Bi 3+ ,0.003Mn 4+ phosphor can be regarded as a prominent FIR-type temperature sensing material. In recent years, more and more attention has been paid to the improvement of accuracy of temperature sensing material. Herein, a new SrGd 2 Al 2 O 7 :Bi 3+ ,Mn 4+ phosphor was designed based on fluorescence intensity ratio in this work.