Selecting Doped Er3+/Ho3+/Tm3+ in the Perovskite-Like Material Cs3YF6: Yb3+ to Achieve Ultrasensitive Luminescence Intensity Ratio Temperature Sensing

Luminescence intensity ratio (LIR) thermometry based on distinct up-conversion luminescence centers was established in Cs-based fluorides. By contrasting the nonthermally coupled luminescence intensity of Er3+/Ho3+/Tm3+, it is possible to determine which kind of up-conversion emission ion is more suited for the perovskite-like Cs3YF6 material. The best option is Er-doped Cs3YF6 samples with a relative sensitivity (Sr) of 0.96% K–1, according to a comparison of the LIR fitting findings. However, the extremely high absolute sensitivity (Sa) in Cs3YF6: Yb, Tm suggests that Sa is not trustworthy in the LIR temperature evaluation system according to the temperature resolution δT. This work provides recommendations for the LIR temperature sensing design for comparable Cs-based fluorides while minimizing time and expense.