Exploring Coumarin-Based Boron Emissive Complexes as Temperature Thermometers in Polymer-Supported Materials

Area of Science:

• Materials Science
• Photochemistry
• Supramolecular Chemistry

Background:

• Development of novel fluorescent materials for sensing applications is crucial.
• Boron complexes offer unique photophysical properties for advanced material design.
• Coumarin derivatives are widely explored for their luminescence characteristics.

Purpose of the Study:

• To design and synthesize novel coumarin-based boron complexes (L1, L2, L3).
• To evaluate their photophysical properties in solution and solid states.
• To investigate their potential as temperature probes when incorporated into polymeric matrices.

Main Methods:

• Synthesis of coumarin-based boron complexes.
• Photophysical characterization (absorption, emission, quantum yield) in various solvents.
• Incorporation into polymeric matrices.
• Evaluation as temperature sensors.
• Computational studies using DFT/B3LYP.

Main Results:

• Compound L1 showed the highest fluorescence quantum yield (33%) in solution with positive solvatochromism.
• L1 exhibited a colorimetric response to anions due to deprotonation.
• Fluorescence quenching at higher temperatures was attributed to torsional vibrations.
• Incorporation into polymers enhanced emission via aggregation.
• The dye@doped polymers demonstrated excellent, reversible temperature sensing over 15 cycles.

Conclusions:

• Coumarin-based boron complexes are promising candidates for fluorescent temperature probes.
• Polymer-incorporated complexes offer enhanced emission and stable sensing capabilities.
• The developed materials show potential for practical applications in temperature sensing.