Luminescence of K2BaCa(PO4)2: Ce3+, Tb3+ dual-emitting phosphor and its application as ratiometric optical thermometer

A new dual-emitting phosphor K2BaCa(PO4)(2): Ce3+, Tb3+ (KBCP: Ce3+, Tb3+) was successfully synthesized and designed to put into application of ratiometric temperature sensing. Under single UV excitation, the developed phosphors shows both Ce3+ violet and Tb3+ green emission mainly at 360 and 542 nm, respectively. The Ce3+-Tb3+ energy transfer process was analyzed by the variation of emission spectra and Ce3+/Tb3+ decay lifetimes. The remarkable thermal stability has also been tested, indicating that the intensity at 200 degrees C is still above 85% of the original intensity. Furthermore, the emission intensity ratio between 360 and 542 nm of KBCP: Ce3+, Tb3+ is found to have a good linear relationship with temperature (R-2 > 0.993), and the corresponding sensitivity temperature resolution is 0.35% K-1 and > 0.02 K, respectively. Thus, this novel dual-emitting phosphor can be used as a potential luminescent thermometer.