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DOE OSTI · 1900020

Hydrogen Crossover Flux through Two-Dimensional Nanomaterials

Gaffrey, Karli Ann·Bukola, Saheed·Blackburn, Jeff·Pivovar, Bryan S.
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Abstract

Energy storage and conversion devices require an ion-exchange membrane with high transmission of charge-balancing ions and separation of anode and cathode electrolytes/gases. This ensures optimum device performance. Most conventional membranes suffer huge cross-permeation resulting in low energy efficiency and material degradation. This work investigated hydrogen permeability and proton transmission through membrane electrode assemblies (MEAs) containing a monolayer of hexagonal boron nitride and single-layer and bi-layer graphene in a gas-phase small-scale cell and a liquid cell. Here we found that the hydrogen crossover flux through MEAs with 2D materials was inhibited by at least a factor of 5 compared to the one without. Single-layer graphene and boron nitride enabled high proton transmission, but bi-layer graphene inhibited proton conduction. Defect visualization of 2D materials revealed few atomic-scale defects in graphene. These findings suggest that a monolayer of 2D material may provide good selectivity for energy conversion and storage devices by blocking species crossover while allowing high proton transmission.

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2D materials77 NANOSCIENCE AND NANOTECHNOLOGYhydrogen crossover fluxhydrogen permeabilitymembrane electrode assembliesproton transmission

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Gaffrey, Karli Ann, Bukola, Saheed, Blackburn, Jeff, Pivovar, Bryan S.. 2022-09-30. Hydrogen Crossover Flux through Two-Dimensional Nanomaterials. https://doi.org/10.1149/10909.0285ecst

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