New article published in Journal of Materials Chemistry A on cross-linked proton-exchange membranes for DIFCs
Cross-linked proton-exchange membranes with strongly reduced fuel crossover and increased chemical stability for direct-isopropanol fuel cells
Isopropanol fuel cells offer an attractive way to provide electric energy from a liquid, easily storable fuel. Within a fuel cell, the isopropanol is converted into acetone without producing significant amounts of CO2. Acetone can be easily hydrogenated back to isopropanol to close the storage cycle, thereby avoiding the sophisticated handling of fugitive molecular hydrogen for storing electrical energy.
Until now, Direct-Isopropanol Fuel Cells (DIFC) usually rely on various perfluorosulfonic acid derivates, like Nafion, which are costly and have an unfavorable high fluorine content. Additionally, the dissolution of Nafion-based membranes and electrodes in isopropanol mixtures has prevented the long-time operation of DIFCs so far. Also, membrane swelling during operation promotes efficiency reducing fuel crossover.
Isopropanol-stable membranes were manufactured by applying ionic cross-linking of polymer blends and a new click-like covalent cross-linking strategy for fluoroaromatic polymers. Compared to commercial Nafion membranes, the manufactured cross-linked membrane resists a dissolution stress test up to 84 w-% and reduces the detected isopropanol/acetone crossover up to 75/100 % during fuel cell operation. Ionic cross-linking increased the maximum power density of DIFC operation by 10 % compared to Nafion.
Consequently, the material and cross-linking procedure can be considered a significant step toward the technical implementation of isopropanol fuel cell technologies.
Read full article here:
Sebastian Auffarth, Willibald Dafinger, Julia Mehler, Valeria Ardizzon, Patrick Preuster, Peter Wasserscheid, Simon Thiele, Jochen Kerres
Cross-linked proton-exchange membranes with strongly reduced fuel crossover and increased chemical stability for direct-isopropanol fuel cells
https://doi.org/10.1039/D2TA03832C
(published 09. August 2022)
Contact
Dr. rer. nat. Jochen Kerres
Team Leader, Membrane Polymer Synthesis
Room 3008
