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arXiv · 1111.6697

Atomic-resolution spectroscopic imaging of ensembles of nanocatalyst particles across the life of a fuel cell

Huolin L. Xin·Julia A. Mundy·Zhongyi Liu·Randi Cabezas·Robert Hovden·Lena Fitting Kourkoutis·Junliang Zhang·Nalini P. Subramanian·Rohit Makharia·Frederick T. Wagner·David A. Muller
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Abstract

The thousandfold increase in data-collection speed enabled by aberration-corrected optics allows us to overcome an electron microscopy paradox - how to obtain atomic-resolution chemical structure in individual nanoparticles, yet record a statistically significant sample from an inhomogeneous population. This allowed us to map hundreds of Pt-Co nanoparticles to show atomic-scale elemental distributions across different stages of the catalyst aging in a proton-exchange-membrane fuel cell, and relate Pt-shell thickness to treatment, particle size, surface orientation, and ordering.

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Huolin L. Xin, Julia A. Mundy, Zhongyi Liu, Randi Cabezas, Robert Hovden, Lena Fitting Kourkoutis, Junliang Zhang, Nalini P. Subramanian, Rohit Makharia, Frederick T. Wagner, David A. Muller. 2011-12-07. Atomic-resolution spectroscopic imaging of ensembles of nanocatalyst particles across the life of a fuel cell. https://doi.org/10.1021/nl203975u

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