Structure, luminescence of Eu2+ and Eu3+ in CaMgSi2O6 and their co-existence for the excitation-wavelength/temperature driven colour evolution

Fang Su; Weijie Zhou; Yunlin Yang; Yiyi Ou; Zeming Qi; Chang-Kui Duan; Mikhail G Brik; Pieter Dorenbos; Hongbin Liang

doi:10.1039/d1dt01377g

Structure, luminescence of Eu²⁺ and Eu³⁺ in CaMgSi₂O₆ and their co-existence for the excitation-wavelength/temperature driven colour evolution

Dalton Trans. 2021 Jul 27;50(29):10050-10058. doi: 10.1039/d1dt01377g.

Authors

Fang Su¹, Weijie Zhou¹, Yunlin Yang¹, Yiyi Ou¹, Zeming Qi², Chang-Kui Duan², Mikhail G Brik³, Pieter Dorenbos⁴, Hongbin Liang¹

Affiliations

¹ MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, P. R. China. cesbin@mail.sysu.edu.cn.
² National Synchrotron Radiation Laboratory, Hefei National Laboratory for Physical Sciences at the Microscale and School of Physical Sciences, University of Science and Technology of China, Hefei 230029, P. R. China.
³ College of Sciences & CQUPT-BUL Innovation Institute, Chongqing University of Posts and Telecommunications, Chongqing 400065, P. R. China and Institute of Physics, University of Tartu, Tartu 50411, Estonia and Institute of Physics, Jan Długosz University, PL-42200 Częstochowa, Poland.
⁴ Faculty of Applied Sciences, Delft University of Technology, 2629 JB, Delft, The Netherlands.

PMID: 34165118
DOI: 10.1039/d1dt01377g

Abstract

Luminescent materials with controllable colour evolution features are demanded for the development of multi-level anti-counterfeiting technologies. Here we report the structural and luminescence properties of CaMgSi2O6:Ln (Ln = Eu2+, Eu3+, Eu2+/3+) samples in detail and reveal their excitation-wavelength/temperature driven colour evolution characteristics. By tuning either the excitation-wavelength (276, 304, 343, 394 nm) or temperature (in the 330-505 K range), the designed samples with co-existing Eu2+/Eu3+ ions can achieve diverse and controllable colour evolution from red, to pink, purple and blue. This shows their potential application in anti-counterfeiting with the help of sophisticated pattern design. In addition, the underlying mechanism of the Stokes shift of the Eu2+ emission and valence stability of both Eu2+/Eu3+ ions in CaMgSi2O6 are also studied in depth. These results are valuable for designing colour-controllable luminescent materials based on the co-existence of the Eu2+/Eu3+ ions for anti-counterfeiting applications.