************第４１回尾張コンプレックスセミナー*************

Title　：　Theoretical Elucidation of Oxygen Transport Mechanism
            though Ionomer of Polymer Electrolyte Fuel Cell

Speaker ：　Akiya Suzuki

Affiliation：　Fuel Cell Research Center, Daido University

Date　：　Fri. Jan. 28th, 1:30 pm (Almost one hour)

Place　：　Seminar Room (4F),
            Graduate School of Information Science

Abstract：
 For polymer electrolyte fuel cell (PEFC), perfluorosulfonate acid
(PFSA) ionomer is mainly utilized as binder of Pt/C catalysts in the
electrode catalyst layer, and as polymer electrolyte membrane.
On the one hand, higher oxygen transport ability is required to the ionomer
used in the cathode catalyst layer in order to increase the utilization of
Pt catalyst and to restrain the diffusion overpotential.
On the other hand, lower oxygen transport ability is required to the ionomer
used in the polymer electrolyte membrane in order to prevent oxygen cross
leakage. It is necessary to investigate oxygen transport mechanism through
the ionomer at the molecular-level, in order to make a molecular design of
ionomer with oxygen transport ability under our perfect control.
 In this study, Nafion was taken for example, which was a kind of PFSA
ionomer, and the model including ionomer, water, and oxygen was constructed.
And molecular dynamics simulations were performed and discussions about
oxygen transport mechanism through the ionomer were conducted. Moreover, as
a result of discussions about oxygen transport ability through hydrocarbon
(HC) ionomer, it was found that oxygen transport ability of HC ionomer was
lower than that of PSFA ionomer. So that the well-known experimental fact
was able to explain theoretically.

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