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Updated: Mar 22, 2026
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
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Unanticipated clustering-triggered emission in ammonium carboxylate salt structures
Hao Zhang1, Yunqian Ma2, Zixu Chen2
1School of Materials Science and Engineering, University of Jinan, Jinan, Shandong 250022, China.
Summary
Ammonium carboxylate salts exhibit intrinsic visible fluorescence through a clustering-triggered emission (CTE) mechanism. This phenomenon shows sensitivity to pH and selective quenching by Fe³⁺ ions.
Area of Science:
- Materials Science
- Photochemistry
- Organic Chemistry
Background:
- Nonconventional fluorophores emitting visible light under UV excitation without external treatment are of significant interest.
- Understanding the photophysical mechanisms of such materials is crucial for developing new optical applications.
Purpose of the Study:
- To report the intrinsic visible emission of ammonium carboxylate salts.
- To elucidate the underlying mechanism responsible for this emission.
- To investigate the environmental sensitivity of the observed fluorescence.
Main Methods:
- Synthesis and characterization of ammonium carboxylate salts.
- Photoluminescence spectroscopy of concentrated solutions and solid powders.
- Single-crystal X-ray diffraction analysis.
- Investigation of pH-dependent fluorescence and selective quenching studies.
Main Results:
- Ammonium carboxylate salts exhibit intrinsic visible fluorescence in concentrated solutions and solid states.
- The emission is attributed to a clustering-triggered emission (CTE) mechanism, supported by structural analysis revealing intermolecular electronic communication.
- The fluorescence demonstrates high sensitivity to pH variations.
- Selective fluorescence quenching was observed in the presence of Fe³⁺ ions.
Conclusions:
- Ammonium carboxylate salts are novel intrinsic visible-light-emitting materials.
- The CTE mechanism provides a new pathway for designing efficient organic fluorophores.
- The pH sensitivity and ion-selective quenching offer potential for sensing applications.
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