Time-dependent Diffusion Coefficient of Proton in Polymer Electrolyte Membrane
نویسندگان
چکیده
We investigated the time-dependent self-diffusion coefficients of water, , in polymer electrolyte membranes at 278 K. The was measured from 0.7 to 100 ms by field gradient NMR techniques. The results showed that the self-diffusion coefficients of water were dependent on less than 2 ms due to restricted diffusion, and were constant beyond 3 ms. The tortuosity and surface-to-volume ratio related to water diffusion were also estimated from . The obtained values revealed the existence of large-scale restricted geometry compared with well-known nanometer-sized domain in polymer electrolyte membranes.
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