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Updated: Sep 20, 2025
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Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
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Tetracoordinated Manganese(II) Halide with Multimode Thermochromic Luminescence for Anticounterfeiting and
Zhaohui Huang1, Xiaoli Wang1, Peng Du1
1Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology, College of Chemistry and Chemical Engineering, Dezhou University, Dezhou, Shandong Province 253023, China.
Inorganic Chemistry
|May 30, 2025
Summary
This study synthesized a manganese(II) halide crystal exhibiting unique, reversible color changes with temperature. This discovery enables advanced temperature-responsive anticounterfeiting and data encryption technologies.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Manganese(II) halides are known for their structural flexibility and optical properties.
- Materials with multimode luminescence color changes under stimuli are rare.
- Developing novel materials for anticounterfeiting and data security is crucial.
Purpose of the Study:
- To synthesize and characterize a novel zero-dimensional manganese(II) halide, (C5H14NO)2MnBr4.
- To investigate its unique thermochromic and luminescence properties.
- To explore its potential applications in anticounterfeiting and information protection.
Main Methods:
- Single crystal synthesis of (C5H14NO)2MnBr4.
- Temperature-dependent X-ray diffraction to study phase transitions.
- Variable-temperature luminescence spectroscopy to analyze emission properties.
Main Results:
- A reversible order-disorder phase transition was observed at 268 K.
- The crystal exhibited a symmetric green-yellow-orange-red-orange-yellow-green luminescence switching from 80-420 K.
- Distinct luminescence mechanisms were identified for the low-temperature phase (Mn(II) d-d transition and self-trapped excitons) and high-temperature phase (trapping and detrapping of self-trapped excitons).
Conclusions:
- The synthesized (C5H14NO)2MnBr4 crystal demonstrates exceptional thermochromic luminescence.
- Its unique properties facilitate the development of advanced temperature-responsive anticounterfeiting labels and multilevel encryption codes.
- This research offers new avenues for designing metal halides with tunable luminescence for security applications.
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