Synergistic modulation of energy transfer and defect engineering toward anti-thermal quenching phosphor for high-sensitivity optical thermometry

Thermal quenching is a critical challenge confronting many phosphors, especially those utilized in the high temperature range, which limits the development of highly sensitive optical thermometry under high temperature conditions. However, it is still quite challenging to obtain anti-thermal quenching phosphor and realize optical thermometry at high temperatures. Herein, a novel co-doped Na3Ca4TeP3O15 (NCTP):Tb3+,Eu3+ phosphor is designed by a facile microwave-assisted solid-state (MASS) reaction, which presents anti-thermal quenching performance. Anti-thermal quenching (109 %@423 K) is realized via the synergistic effect of energy transfer and manipulation of defects by MASS. In view of the significantly different response of Tb3+/Eu3+ to temperature, the luminescence intensity ratio (LIR) readout is designed for non-contact optical thermometry with maximum absolute (Sa) and relative (Sr) sensitivities of 5.61×10−2 K−1 and 4.43 % K−1, respectively. The strategy of designing anti-thermal quenching phosphor is expected to open up new research avenues for realizing optical thermometry at high temperatures.