Organic BODIPY Based Gels: Optical, Electrochemical and Self-Assembly Properties

Area of Science:

• Materials Science
• Organic Chemistry
• Supramolecular Chemistry

Background:

• BODIPY dyes are valuable fluorophores with tunable optical properties.
• Self-assembly of organic molecules is key for developing advanced materials.
• Alkyl chain length significantly influences molecular assembly and material properties.

Purpose of the Study:

• To synthesize and characterize novel BODIPY dyes with variable alkyl chains.
• To investigate the effect of alkyl chain length on self-assembly and photophysical properties.
• To evaluate the potential of these dyes for organic electronic applications.

Main Methods:

• Synthesis of BOC3 and BC12 BODIPY dyes.
• Spectroscopic analysis (absorption, emission) in solution and film states.
• Density Functional Theory (DFT) calculations for electronic structure.
• Transient photoluminescence spectroscopy.
• Gelation studies.

Main Results:

• BC12, with a longer alkyl chain, formed a gel through supramolecular self-assembly, unlike BOC3.
• Both dyes showed red-shifted absorption (approx. 30 nm) in film state due to π-π stacking and aggregation.
• DFT calculations (O3LYP) correlated well with experimental absorption spectra.
• BC12 exhibited a longer excited-state lifetime (5.28 ns) than BOC3 (4.50 ns).
• BC12 formed spherical nano-networks via self-assembly.

Conclusions:

• Molecularly tuning BODIPY dyes with alkyl chains enables controlled supramolecular self-assembly.
• The longer alkyl chain in BC12 promotes gelation and nano-network formation.
• These dyes possess suitable electronic properties (HOMO/LUMO levels) for organic electronics.
• Self-assembly-induced red shifts are critical for optimizing optical properties in solid-state applications.