%0 Journal Article
%A Gisuk Hwang
%A Dilworth Y Parkinson
%A Ahmet Kusoglu
%A Alastair A MacDowell
%A Adam Z Weber
%B ACS Macro Letters
%D 2013
%N 4
%P 288 - 291
%R 10.1021/mz300651a
%T Understanding Water Uptake and Transport in Nafion Using X-ray Microtomography
%V 2
%8 04/2013
%! ACS Macro Lett.
%X <p>To develop new ionomers and optimize existing ones, there is a need to understand their structure/function relationships experimentally. In this letter, synchrotron X-ray microtomography is used to examine water distributions within Nafion, the most commonly used ionomer. Simultaneous high spatial (~1 μm) and temporal (~10 min) resolutions, previously unattained by other techniques, clearly show the nonlinear water profile across the membrane thickness, with a continuous transition from dynamic to steady-state transport coefficients with the requisite water-content dependence. The data also demonstrate the importance of the interfacial condition in controlling the water profile and help to answer some long-standing debates in the literature.</p>