Molded, high surface area polymer electrolyte membranes from cured liquid precursors

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Polymer electrolyte membranes (PEMs) are crucial components in fuel cells.
• Conventional PEMs often face challenges with water solubility and processing limitations.
• Achieving high proton conductivity without compromising mechanical integrity is a key challenge.

Purpose of the Study:

• To develop novel, easily processable polymer electrolyte membranes (PEMs) for fuel cells.
• To enhance proton conductivity and overcome water solubility issues in PEMs.
• To explore the use of patterned membranes for improved fuel cell performance.

Main Methods:

• Synthesis of PEMs from low molecular weight, 100% curable liquid precursors.
• Photochemical curing to form solid membranes with desired dimensions.
• Incorporation of acidic groups via chemical cross-linking.
• Fabrication of membrane electrode assemblies (MEAs) using both flat and patterned PEMs.
• Soft lithography and micromolding techniques for creating 3D patterned membranes.

Main Results:

• Highly proton conductive solid PEMs were successfully synthesized directly from liquid precursors.
• Cross-linking prevented water solubility while allowing high levels of acidic groups for conductivity.
• Fuel cells utilizing these PEMs demonstrated superior performance compared to commercial materials.
• Patterned PEMs created via soft lithography yielded larger interfacial areas and higher power densities in MEAs.
• 3D patterned membranes achieved higher power densities without increasing the overall fuel cell size.

Conclusions:

• The developed liquid precursor route offers a versatile and efficient method for fabricating advanced PEMs.
• Chemical cross-linking is effective in achieving high proton conductivity and material stability.
• Patterned PEMs represent a promising strategy for miniaturizing fuel cells and enhancing power density for portable applications.