VUV–UV–vis Luminescence, Energy Transfer Dynamics, and Potential Applications of Ce<sup>3+</sup>- and Eu<sup>2+</sup>-Doped CaMgSi<sub>2</sub>O<sub>6</sub>
Fang Su, Bibo Lou, Yiyi Ou, Yunlin Yang, Weijie Zhou, Chang‐Kui Duan, H. Liang
Abstract
Ce3+ and Eu2+ single- and double-doped CaMgSi2O6 phosphors have been prepared by a high-temperature solid-state reaction approach. The VUV–UV–vis luminescence properties are investigated at cryogenic temperatures. The dependencies of luminescence intensity and lifetime on temperature are discussed in detail, and the different thermal-quenching characteristics of luminescence of Ce3+ and Eu2+ in CaMgSi2O6 are revealed combined with the VRBE scheme. Because of the different energy barriers of the lowest 5d energy and the conduction band bottom, luminescence thermal quenching of Ce3+ does not occur below about 505 K, but that of Eu2+ arises at a temperature above ∼300 K. The energy transfer dynamics is then analyzed by using the Inokuti-Hirayama, Yokota-Tanimoto, and Burshteı̆n models, respectively. The Ce3+–Eu2+ energy transfer is mainly through the electric dipole–dipole interaction with a critical distance of about 21.2 Å, and the energy migration between Ce3+ ions in a fast or slow way is negligible. The different thermal-quenching behaviors of Ce3+ and Eu2+ luminescence and their energy transfer pave the way for the potential applications of the codoped samples in optical thermometry and anticounterfeiting.