A supramolecular cross-linked conjugated polymer network for multiple fluorescent sensing.

Area of Science:

• Supramolecular chemistry
• Materials science
• Chemical sensing

Background:

• Fluorescent conjugated polymers are widely used in sensing applications.
• Supramolecular chemistry offers unique opportunities for designing advanced functional materials.
• Host-guest interactions provide a mechanism for stimuli-responsive material design.

Purpose of the Study:

• To fabricate a supramolecular cross-linked network for multiple fluorescent sensing.
• To investigate the stimuli-responsive properties of the network based on host-guest interactions.
• To evaluate the network's potential for detecting various analytes including ions, pH, temperature, and gases.

Main Methods:

• Fabrication of a supramolecular cross-linked network using a fluorescent conjugated polymer and a bisammonium salt cross-linker.
• Utilizing dibenzo[24]crown-8/secondary ammonium salt host-guest interactions for network construction.
• Characterization of the network's fluorescence response to different stimuli (potassium cation, chloride anion, pH, temperature, ammonia gas).

Main Results:

• The supramolecular network exhibited weak fluorescence due to polymer chain aggregation.
• Host-guest interactions enabled enhanced fluorescence in response to potassium cations, chloride anions, pH increase, and heating.
• The material demonstrated effective sensing capabilities in both solution and thin film formats.
• Ammonia gas exposure led to a notable increase in fluorescence intensity.

Conclusions:

• The developed supramolecular cross-linked network functions as a multi-responsive fluorescent sensor.
• The material shows promise for detecting a range of chemical species and physical parameters.
• Its application in gas detection, particularly for ammonia, highlights its versatility.