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Proton Conduction in Tröger's Base-Linked Poly(crown ether)s
Hasmukh A Patel, John Selberg1, Dhafer Salah2
1Department of Electrical Engineering , University of California Santa Cruz , Santa Cruz , California 95064 , United States.
ACS Applied Materials & Interfaces
|June 6, 2018
Summary
New polymers incorporating dibenzo[18]crown-6 (DB18C6) exhibit proton conductivity in humid conditions due to water adsorption and hydrogen bonding. These materials form stable membranes with potential applications in supramolecular chemistry.
Area of Science:
- Supramolecular Chemistry
- Polymer Science
- Materials Science
Background:
- Dibenzo[18]crown-6 (DB18C6) is a key molecule in supramolecular and host-guest chemistry.
- Proton conductivity is crucial for various energy applications.
- Developing novel materials with tailored properties is an ongoing challenge.
Purpose of the Study:
- To synthesize and characterize novel Tröger's base-linked polymers incorporating DB18C6.
- To investigate the proton conductivity of these polymers under humid conditions.
- To explore the potential applications of these new materials.
Main Methods:
- Synthesis of poly(TBL-DB18C6)-t and poly(TBL-DB18C6)-c via in situ alkylation and cyclization.
- Characterization of macromolecular structures using spectroscopic techniques and size-exclusion chromatography.
- Measurement of water vapor adsorption and proton conductivity.
Main Results:
- High-molecular-weight polymers with excellent solubility and film-forming ability were successfully synthesized.
- The polymers exhibit significant water uptake (23 wt%) and retain adsorbed water under varying humidity.
- Proton conductivity of 1.4 × 10⁻⁴ mS cm⁻¹ was achieved in humid environments, attributed to hydrogen bonding and proton hopping.
Conclusions:
- Tröger's base-linked polymers with DB18C6 demonstrate promising proton conductivity for applications in humid environments.
- The materials' robust film-forming ability and the presence of crown ether cavities open avenues for diverse applications.
- This work expands the utility of DB18C6 in advanced functional materials.
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