Site Occupancies, Electron–Vibration Interaction and Energy Transfer of CaMgSi2O6: Eu2+, Mn2+ Phosphors for Potential Temperature‐Sensing and Anti‐counterfeiting Applications.

Eu2+‐, Mn2+‐ and Eu2+−Mn2+‐doped CaMgSi2O6 phosphors have been prepared by a high‐temperature solid‐state reaction. Systematic investigation of the concentration‐ and temperature‐dependent luminescence of Mn2+ showed that Mn2+ ions occupy two distinct sites in CaMgSi2O6. Electron–vibration interaction (EVI) analyses of Mn2+ ions revealed Huang–Rhys factors of 4.73 and 2.82 as well as effective phonon energies of 313 and 383 cm−1 for the two sites. Eu2+−Mn2+ energy transfer is also discussed, and its efficiency is estimated by lifetime and luminescence spectra. The different thermal quenching behaviours of Eu2+ and Mn2+, the distinct emission colours of Eu2+ (blue, band peak at ∼451 nm) and Mn2+ (yellow–red range, band peaks at ∼583 and 693 nm) endow the co‐doped samples with potential applications in luminescence thermometry and temperature‐/excitation wavelength‐responsive dual anti‐counterfeiting. [ABSTRACT FROM AUTHOR]