Optical temperature sensing of four modes by using CsPb(Cl/Br)3 quantum dots and Tb3+ ions co-doping glass

We have fabricated CsPb(Cl/Br)3 quantum dots (QDs) and Tb3+ co-doping glass and comparatively investigated four-mode temperature sensing of fluorescence intensity ratio (FIR), full width at half maximum (FWHM), lifetime and chromatic coordinate. Temperature dependent photoluminescence (PL) spectra are measured. The Tb3+ ions and CsPb(Cl/Br)3 QDs have independent luminescence and FIR of Tb3+ to QDs has obvious decrease with temperature, which is used for FIR temperature sensing. The PL and PL decay of QDs are used for FWHM and lifetime temperature sensing. The change of FIR with temperature leads to the change of luminous color and chromatic coordinate with temperature. A new chromatic temperature sensing method is established, which utilizes linear relation of chromatic coordinate and temperature. Temperature dependence for FIR, FWHM, lifetime and chromatic coordinate has been fitted. Absolute sensitivity, relative sensitivity, temperature accuracy and repeatability have been evaluated. Among the four sensing modes, the FIR and chromatic coordinate modes have large sensitivity and small accuracy. The FIR mode is better than chromatic coordinate mode in absolute sensitivity and relative sensitivity, whereas the chromatic coordinate mode is better in its good linear relation. The four sensing modes have excellent repeatability due to the stability of QDs-Tb3+ co-doping glass.