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Analysis of the oxygen scattering behaviour on ionomer surface in catalyst layer of PEFC

Masataka Nakauchi, Takuya Mabuchi, Ikuya Kinefuchi, Hideki Takeuchi, Takashi Tokumasu

2016/5/20

Abstract

Mass transport significantly affects the reaction efficiency of polymer electrolyte fuel cells. In particular, the oxygen transport in catalyst layers is important for the improvement of its efficiency. However, the mechanism of oxygen scattering on ionomer surface, which is one of the dominant factors of transport phenomena, has not been clarified. Therefore, we analyzed the oxygen scattering behaviour on ionomer surface using molecular dynamics simulation. Oxygen molecules are impinged to ionomer surface with different incident energies and angles. According to the total energy of oxygen molecule, the trajectories of oxygen molecules are classified into trapping or scattering. The trapping probability of oxygen molecule on ionomer surface decreases as the normal component of the incident energy increases. Oxygen molecules with low normal incident energy get energy during the gas–surface interaction on the surface and desorb from the surface. The number of collisions with the surface does not affect the energy transfer between oxygen molecule and ionomer surface.

Published in: Renewable Energy & Power Quality Journal (RE&PQJ, Nº. 14)
Pages:349-352 Date of Publication: 2016/5/20
ISSN: 2172-038X Date of Current Version:2016/05/04
REF:315-16 Issue Date: May 2016
DOI:10.24084/repqj14.315 Publisher: EA4EPQ

Authors and affiliations

Masataka Nakauchi(1), Takuya Mabuchi(1), Ikuya Kinefuchi(2), Hideki Takeuchi(3), Takashi Tokumasu(4)
1. Graduate School of Engineering, Tohoku University ,Sendai, Miyagi. Japan
2. Department of Mechanical Engineering, The University of Tokyo. Japan
3. Department of Mechanical Engineering, National Institute of Technology, Kochi College. Japan
4. Institute of Fluid Science, Tohoku University. Japan

Key words

Polymer Electrolyte Fuel Cell, Rarefied Gas Dynamics, Molecular Dynamics Simulation, Scattering Behaviour

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