(Invited) Development of PFSA Ionomers for the Membrane and the Electrodes

The key to address the cost issue of polymer electrolyte membrane fuel cells (PEMFCs) lies on reducing Pt amount employed in cathode catalyst layers (CCLs). In past decades, researchers focus on developing series of alloy and core–shell electrocatalysts with high oxygen reduction reaction activity in order to alleviate the low Pt loading caused performance loss. However, it is noted that the concentration polarization loss resulting from the cathode oxygen transport plays a more important role as the Pt loading decreases, especially the local oxygen transport through the ultrathin ionomer film covering on Pt surface. This paper reviews the nanomorphology of the ultrathin perfluorinated sulfonic acid ionomer film in CCLs, as well as the local oxygen transport mechanism and the corresponding effects on fuel cell performance in low Pt PEMFCs. In addition, both the detailed local oxygen transport properties in carbon black‐supported Pt membrane electrode assemblies (MEAs) and high surface carbon‐supported MEAs are summarized. Subsequently, numerous innovative strategies and effective approaches of reducing the local oxygen transport resistance are introduced. The new insights proposed in this paper have important implications for enhancing local oxygen transport and designing high‐performance fuel cell electrodes.

show abstract

Section: Strategies To Reduce Rlocalmentioning

confidence: 99%

Perspectives on Challenges and Achievements in Local Oxygen Transport of Low Pt Proton Exchange Membrane Fuel Cells

Cheng

Shen

Wei

et al. 2022

Adv Materials Technologies

View full text Add to dashboard Cite

show abstract

“…The most significant impact observed is when a small cyclical ring is inserted into the ionomer backbone in order to create a sterically enhanced O 2 permeability through a more open structure (Fig. 9) [100][101][102]. This results in a substantial improvement in HCD voltage as shown in Fig.…”

Section: Ionomer Thin Film and Ionomer-pt Interfacementioning

confidence: 99%

Proton-Exchange Membrane Fuel Cells with Low-Pt Content

Kongkanand¹,

Gu²,

Mathias

2017

Encyclopedia of Sustainability Science and Technology

View full text Add to dashboard Cite

Widespread commercialization of fuel cell electric vehicles (FCEV) relies on further reduction of PGM (platinum group metals) usage. Although enhancements in the activity and stability of the catalyst are necessary, those alone are insufficient. In a fuel cell with low PGM content, transport of reactants (oxygen and protons) to a small area of catalyst can cause large performance loss at high power. Because it is this high-power point that determines the required fuel cell area, these losses drive up the size, and thus the cost, of the fuel cell stack. This entry discusses fuel cell cost reduction with special focus on the challenges and opportunity associated with Pt reduction. Proton-Exchange Membrane Fuel Cells with Low-Pt Content, Fig. 1 Impact of fuel cell vehicles on Pt consumption (Reprinted with permission from Ref. [7].

show abstract

“…Attempts to improve O 2 permeability through a more open structure ionomer are also being pursued with encouraging results. − A basic strategy is to insert a small cyclical ring into the backbone to create a sterically enhanced O 2 permeability (Figure b). It was shown that this strategy could increase O 2 permeability by a factor of 2–20 in a bulk membrane.…”

mentioning

confidence: 99%

The Priority and Challenge of High-Power Performance of Low-Platinum Proton-Exchange Membrane Fuel Cells

Kongkanand

Mathias

2016

J. Phys. Chem. Lett.

1,004

1,075

View full text Add to dashboard Cite

Substantial progress has been made in reducing proton-exchange membrane fuel cell (PEMFC) cathode platinum loadings from 0.4-0.8 mgPt/cm(2) to about 0.1 mgPt/cm(2). However, at this level of cathode Pt loading, large performance loss is observed at high-current density (>1 A/cm(2)), preventing a reduction in the overall stack cost. This next developmental step is being limited by the presence of a resistance term exhibited at these lower Pt loadings and apparently due to a phenomenon at or near the catalyst surface. This issue can be addressed through the design of catalysts with high and stable Pt dispersion as well as through development and implementation of ionomers designed to interact with Pt in a way that does not constrain oxygen reduction reaction rates. Extrapolating from progress made in past decades, we are optimistic that the concerted efforts of materials and electrode designers can resolve this issue, thus enabling a large step toward fuel cell vehicles that are affordable for the mass market.

show abstract

(Invited) Development of PFSA Ionomers for the Membrane and the Electrodes

Cited by 19 publications

References 2 publications

Perspectives on Challenges and Achievements in Local Oxygen Transport of Low Pt Proton Exchange Membrane Fuel Cells

Perspectives on Challenges and Achievements in Local Oxygen Transport of Low Pt Proton Exchange Membrane Fuel Cells

Proton-Exchange Membrane Fuel Cells with Low-Pt Content

The Priority and Challenge of High-Power Performance of Low-Platinum Proton-Exchange Membrane Fuel Cells

Contact Info

Product

Resources

About