Model of cathode catalyst layers for polymer electrolyte fuel cells: The role of porous structure and water accumulation

Liu, Jianfeng; Eikerling, Michael

doi:10.1016/j.electacta.2008.01.033

Cited by 77 publications

(60 citation statements)

References 35 publications

(50 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: -16mentioning

confidence: 99%

“…For further improvements of performance models, it is, therefore, vital to understand the structure of interfaces and the heterogeneous wettability in CCL. 19,23,26,27 Molecular dynamics (MD) simulations provide valuable insights into microscale structure and transport properties of CLs. [28][29][30][31][32] Malek et al 28 introduced a model based on coarsegrained molecular dynamics to study the self-organized microstructure in CLs.…”

Section: Introductionmentioning

confidence: 99%

“…[19][20][21][22][23][24][25][26][27] Many assumptions have been made due to the lack of experimental evidence. The water uptake isotherm of the Nafion membrane was used to describe water uptake properties of Nafion ionomer in CLs.…”

Section: Introductionmentioning

confidence: 99%

“…The water uptake isotherm of the Nafion membrane was used to describe water uptake properties of Nafion ionomer in CLs. [19][20][21][22][23][24] The transport properties of water and protons were inferred from the values for the Nafion membrane, [19][20][21][22][23][24][25][26][27] as well. These assumptions are largely uncorroborated since the morphology of the ionomer in CLs and the water uptake and distribution in CLs are different from those in the Nafion membrane.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Molecular Dynamics Study of Ionomer and Water Adsorption at Carbon Support Materials

et al. 2010

Self Cite

View full text Add to dashboard Cite

Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n'arrivez pas à les repérer, communiquez avec nous à PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. Questions? Contact the NRC Publications Archive team atPublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. If you wish to email the authors directly, please see the first page of the publication for their contact information. NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://doi.org/10.1021/jp1034135Access and use of this website and the material on it are subject to the Terms and Conditions set forth at Molecular dynamics study of ionomer and water adsorption at carbon support materials Mashio, Tetsuya; Malek, Kourosh; Eikerling, Michael; Ohma, Atsushi; Kanesaka, Hiroyuki; Shinohara, Kazuhiko http://nparc.cisti-icist.nrc-cnrc.gc.ca/fra/droits L'accès à ce site Web et l'utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D'UTILISER CE SITE WEB. NRC Publications Record / Notice d'Archives des publications de CNRC:http://nparc.cisti-icist.nrc-cnrc.gc.ca/eng/view/object/?id=e0f8664e-92a9-4fa6-ae25-0e8aa91cf434 http://nparc.cisti-icist.nrc-cnrc.gc.ca/fra/voir/objet/?id=e0f8664e-92a9-4fa6-ae25-0e8aa91cf434 Research Center, Nissan Motor Co., Ltd., 1 Natsushima-cho, Yokosuka-shi, Kanagawa 237-8523, Japan, National Research Council Canada Institute for Fuel Cell InnoVation, 4250 Wesbrook Mall, VancouVer, British Columbia V6T 1W5, Canada, and Department of Chemistry, Simon Fraser UniVersity, Burnaby, British Columbia, Canada V5A 1S6 ReceiVed: April 16, 2010; ReVised Manuscript ReceiVed: June 16, 2010 Molecular dynamics simulations were applied to unravel the microscopic structure of Nafion ionomer and water adsorbed at graphitized carbon sheets. The considered molecular model resembles microscopic interfaces at which current generation proceeds in catalyst layers of polymer electrolyte fuel cells. The analysis of equilibrated interfacial configurations shows that Nafion ionomer forms a thin adhesive film on the graphite sheet. At low water content, water molecules form clusters around sulfonic acid groups. At high water content, a continuous water film wets the ionomer surface. The structural analysis of this model did not provide any evidence for interconnected water clusters existing inside the ionomer film, which implies that hydronium ion transport will occur mainly along hydrated ionomer ...

show abstract

Section: -16mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Molecular Dynamics Study of Ionomer and Water Adsorption at Carbon Support Materials

et al. 2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…17,19,21,23 The works that do consider flooding are primarily concerned with thin, precious-metal catalyzed layers of ∼10 μm thickness. 19,21 In the present work, we consider the impact of flooding on both electrochemically active surface area (ECSA) and gas diffusion in catalyst layers of 60-120 μm thickness.…”

mentioning

confidence: 99%

Modeling of Low-Temperature Fuel Cell Electrodes Using Non-Precious Metal Catalysts

Leonard

Artyushkova

Halevi³

et al. 2015

J. Electrochem. Soc.

View full text Add to dashboard Cite

An electrode-scale, transport model for a proton-exchange-membrane fuel cell (PEMFC) cathode is presented. The model describes the performance of non-precious metal catalysts for the oxygen reduction reaction in a fuel cell context. Because of its relatively high thickness, emphasis is placed on phenomena occurring in the cathode layer. Water flooding is studied in terms of its impact on gas-phase transport and on electrochemically accessible surface area (ECSA). Although cathode performance in both air and oxygen are susceptible to ECSA loss, gas diffusion limitations at high current density in air are more significant. In oxygen, catalyst utilization at high current density is primarily limited by conductivity. For this reason, air fuel cell data is recommended over oxygen data for characterizing catalyst performance. Due to both ohmic and mass transport limitations, increased loading of low-cost catalysts does not necessarily lead to higher performance. Therefore, careful optimization of catalyst layer thickness is required. The high environmental costs of current energy systems drives a search for commercializable energy technologies with low carbon footprints. Proton exchange membrane fuel cells present one energy option for transportation applications. A significant impediment to commercialization has been the cost and availability of catalysts for the oxygen reduction reaction (ORR) due to prevalent use of platinum group metals (PGM). Metal-Nitrogen-Carbon (MNC) catalysts are a potential solution to the cost and availability challenges that come with using PGMs. MNC catalysts are synthesized by mixing metal, carbon, and nitrogen precursors followed by one or more pyrolysis steps at 700-900 C.1-8 Such MNC catalysts are generally washed in acid to remove excess metal precursors.1-5 These catalysts generally involve lower volume-specific activity than platinum, which results in thicker electrodes. It has been previously proposed that a low-cost catalyst may be allowed to have 10-fold lower activity than platinum, as long as the catalyst layer was 10-fold thicker.9 This proposal was based on the assumption that transport loses would not be significant in this thickness regime. The purpose of this paper is to understand quantitatively how the thickness of these electrodes will impact membrane electrode assembly (MEA) performance for MNC catalyst.A number of models have addressed electrode scale transport issues.10-16 These models generally concentrate on water flooding in the gas diffusion layer (GDL) and consider a relatively thin catalyst layer. Here, gas and liquid transport in the catalyst layer are considered in a way that is similar to treatment of gas diffusion layers in previous models. We also treat the GDL consistently with previous models.Multiple works have addressed gas diffusion in the cathode catalyst layers, 17-23 with a subset considering flooding impacts on gas diffusion. 17,19,21,23 The works that do consider flooding are primarily concerned with thin, precious-metal catalyzed layers of ∼10 ...

show abstract

Nanoscale Phenomena in Catalyst Layers for PEM Fuel Cells: From Fundamental Physics to Benign Design

et al. 2010

Self Cite

View full text Add to dashboard Cite

Model of cathode catalyst layers for polymer electrolyte fuel cells: The role of porous structure and water accumulation

Cited by 77 publications

References 35 publications

Molecular Dynamics Study of Ionomer and Water Adsorption at Carbon Support Materials

Molecular Dynamics Study of Ionomer and Water Adsorption at Carbon Support Materials

Modeling of Low-Temperature Fuel Cell Electrodes Using Non-Precious Metal Catalysts

Nanoscale Phenomena in Catalyst Layers for PEM Fuel Cells: From Fundamental Physics to Benign Design

Contact Info

Product

Resources

About