Photoluminescence and optical temperature measurement of Mn/Er co-activated double perovskite phosphor through site-advantageous occupation.

Because traditional methods based on thermal coupling energy level temperature measurement have large errors, a new temperature sensing strategy is proposed to attain strong sensitivity and excellent signal resolution ability. The rare-earth and also transition metal ions with poles apart thermal quenching channels are used as dual emission centers to find a suitable host to achieve high-efficiency dual-mode emission. In this work, a string of phosphors with NaLaMgWO (NLMW) as the host, the single-doped and double-doped Mn and Er phosphors were adopted by the traditional high temperature solid-state reaction method. The crystallographic structure of the phosphor was analyzed by X-ray power diffraction and Rietveld refinement methods, and the results showed that a pure double perovskite phosphor with a monoclinic structure was successfully prepared. The photoluminescence excitation and emission spectrum properties, CIE chromaticity coordinates and photoluminescence spectra at different temperatures are detailed studied. Excited by ultraviolet light (300 nm), corresponding to the A→T transition of Mn and the charge transfer from O to W of Er. There is no energy transfer between Mn and Er. NLMW:Mn/Er phosphors were especially sensitive to temperature changes within the scope of 303 K to 523 K. As the temperature increases, the fluorescence intensity of Mn is thermally quenched faster than Er. The luminescent intensity ratio of Er thermal coupling level and the FIR of Er/Mn are used to study the temperature performance. The results show that the maximum relative sensitivity of FIR up to 1.31% K, which is higher than the maximum temperature sensitivity based on the thermal coupling energy level, and which is beyond most of the non-contact temperature measurement materials previously reported, confirming that NLMW:Mn/Er phosphors have application potential in non-contact temperature measurement.