1. Dynamic sparse x-ray nanotomography reveals ionomer hydration mechanism in polymer electrolyte fuel-cell catalyst.
- Author
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Zirui Gao, Appel, Christian, Holler, Mirko, Jeschonek, Katharina, Brunnengräber, Kai, Etzold, Bastian J. M., Kronenberg, Michal, Stampanoni, Marco, Ihli, Johannes, and Guizar-Sicairos, Manuel
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COMPUTED tomography , *TOMOGRAPHY , *POLYELECTROLYTES , *DRINKING (Physiology) , *SPEED measurements , *IONOMERS - Abstract
Tomographic imaging of time-evolving samples is a challenging yet important task for various research fields. At the nanoscale, current approaches face limitations of measurement speed or resolution due to lengthy acquisitions. We developed a dynamic nanotomography technique based on sparse dynamic imaging and 4D tomography modeling. We demonstrated the technique, using ptychographic x-ray computed tomography as its imaging modality, on resolving the in situ hydration process of polymer electrolyte fuel cell (PEFC) catalyst. The technique provides a 40-time increase in temporal resolution compared to conventional approaches, yielding 28 nm half-period spatial and 12 min temporal resolution. The results allow a quantitative characterization of the water intake process inside PEFC catalysts with nanoscale resolution, which is crucial for understanding their electrochemical mechanisms and optimizing their performance. Our technique enables high-speed operando nanotomography studies and paves the way for wider application of dynamic tomography at the nanoscale. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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