Influence of the Catalyst Layer Structure Formed by Inkjet Coating Printer on PEFC Performance

In this study, we investigated the influence of the Catalyst-Layer (CL) structure on Polymer Electrolyte Fuel Cell (PEFC) performance using an inkjet coating printer, and we especially focused on the CL thickness and the electrode area. In order to evaluate the influence of CL thickness, we prepared four Membrane Electrode Assemblies (MEAs), which have one, four, five and six CLs, respectively, and evaluated it by an overpotential analysis. As a result, the overpotentials of an activation and a diffusion increased with the increase of thickness of CL. From Energy Dispersive X-ray spectroscopy (EDX) analysis, because platinum twines most ionomers and precipitates, the CL separates into a layer of platinum with a big grain aggregate ionomer and the mixing layer of platinum and ionomer during the catalyst ink drying process. Consequently, the activation overpotential increased because the three-phase interface was not able to be formed sufficiently. The gas diffusivity of the multilayer catalyst electrode was worse than that of a single layer MEA. The influence of the electrode area was examined by two MEAs with 1 and 9 cm2 of electrode area. As a result, the diffusion overpotential of 9 cm2 MEA was worse than 1 cm2 MEA. The generated condensate was multiplied and moved to the downstream side, and thereafter it caused the flooding/plugging phenomena.

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Influence of Ammonia on Membrane-Electrode Assemblies in Polymer Electrolyte Fuel Cells

ASME 2009 7th International Conference on Fuel Cell Science, Engineering and Technology ◽

10.1115/fuelcell2009-85041 ◽

2009 ◽

Cited By ~ 1

Author(s):

Xiaoyu Zhang ◽

Joshua Preston ◽

Ugur Pasaogullari ◽

Trent Molter

Keyword(s):

Polymer Electrolyte ◽

Electrochemical Impedance ◽

Polymer Electrolyte Membrane ◽

Catalyst Layer ◽

Polymer Electrolyte Fuel Cell ◽

Membrane Electrode ◽

Electrolyte Membrane ◽

Catalyst Layers ◽

Electrode Assemblies ◽

And Performance

An experimental investigation of contamination of polymer electrolyte fuel cell (PEFC) membranes and catalyst layers with ammonia (NH3) is reported. Cyclic voltammetry (CV) scans and electrochemical impedance spectroscopy (EIS) analyses show that trace amounts of ammonia can significantly contaminate both the polymer electrolyte membrane (PEM) and the catalyst layers. The results show that the catalyst layer contamination can be reversed under certain conditions, while the membrane recovery tends to be much slower, and permanent effects of ammonia contamination is observed. Mechanisms of contamination of the polymer electrolyte and catalyst layers, and performance degradation of the PEFC are also postulated.

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High performance membrane electrode assemblies by optimization of coating process and catalyst layer structure in direct methanol fuel cells

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2011.01.068 ◽

2011 ◽

Vol 36 (8) ◽

pp. 5096-5103 ◽

Cited By ~ 31

Author(s):

Daejong You ◽

Yoonhoi Lee ◽

Hyejung Cho ◽

Joon-Hee Kim ◽

Chanho Pak ◽

...

Keyword(s):

Fuel Cells ◽

High Performance ◽

Direct Methanol Fuel Cells ◽

Layer Structure ◽

Catalyst Layer ◽

Membrane Electrode ◽

Coating Process ◽

Electrode Assemblies ◽

Direct Methanol ◽

Methanol Fuel Cells

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Scalable Sacrificial Templating to Increase Porosity and Platinum Utilisation in Graphene-Based Polymer Electrolyte Fuel Cell Electrodes

Nanomaterials ◽

10.3390/nano11102530 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2530

Author(s):

Theo A. M. Suter ◽

Adam J. Clancy ◽

Noelia Rubio Carrero ◽

Marie Heitzmann ◽

Laure Guetaz ◽

...

Keyword(s):

Carbon Black ◽

Polymer Electrolyte ◽

Catalyst Layer ◽

Carbon Support ◽

Polymer Electrolyte Fuel Cell ◽

Great Promise ◽

Membrane Electrode ◽

Fuel Cell Electrodes ◽

Electrode Assemblies ◽

Non Destructive

Polymer electrolyte fuel cells hold great promise for a range of applications but require advances in durability for widespread commercial uptake. Corrosion of the carbon support is one of the main degradation pathways; hence, corrosion-resilient graphene has been widely suggested as an alternative to traditional carbon black. However, the performance of bulk graphene-based electrodes is typically lower than that of commercial carbon black due to their stacking effects. This article reports a simple, scalable and non-destructive method through which the pore structure and platinum utilisation of graphene-based membrane electrode assemblies can be significantly improved. Urea is incorporated into the catalyst ink before deposition, and is then simply removed from the catalyst layer after spraying by submerging the electrode in water. This additive hinders graphene restacking and increases porosity, resulting in a significant increase in Pt utilisation and current density. This technique does not require harsh template etching and it represents a pathway to significantly improve graphene-based electrodes by introducing hierarchical porosity using scalable liquid processes.

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Catalyst layer cracks by buckling deformation of membrane electrode assemblies under humidity cycles and mitigation methods

Journal of Power Sources ◽

10.1016/j.jpowsour.2013.04.026 ◽

2013 ◽

Vol 238 ◽

pp. 403-412 ◽

Cited By ~ 31

Author(s):

Tomoaki Uchiyama ◽

Hideyuki Kumei ◽

Toshihiko Yoshida

Keyword(s):

Catalyst Layer ◽

Membrane Electrode ◽

Membrane Electrode Assemblies ◽

Electrode Assemblies ◽

Mitigation Methods

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Development of Production Technology for Membrane-Electrode Assemblies With Radical Capturing Layer

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4023218 ◽

2013 ◽

Vol 10 (1) ◽

Cited By ~ 2

Author(s):

Toshiro Kobayashi ◽

Etsuro Hirai ◽

Hideki Itou ◽

Takuya Moriga

Keyword(s):

Production Technology ◽

Mass Production ◽

Catalyst Layer ◽

Gas Diffusion ◽

Membrane Electrode ◽

Continuous Formation ◽

Forming Technology ◽

Membrane Electrode Assemblies ◽

Electrode Assemblies ◽

Opening Ratio

This paper describes the development of mass-production technology for membrane-electrode assemblies (MEA) with a radical capturing layer and verifies its performance. Some of the authors of this paper previously developed an MEA with a radical capturing layer along the boundaries between the electrode catalyst layer and the polymer membrane to realize an endurance time of 20,000 h in accelerated daily start and daily stop (DSS) deterioration tests. Commercialization of these MEAs requires a production technology that suits mass production lines and provides reasonable cost performance. After developing a water-based slurry and selecting a gas diffusion layer (GDL), a catalyst layer forming technology uses a rotary screen method for electrode formation. Studies confirmed continuous formation of the catalyst layer, obtaining an anode/cathode thickness of 55 μm (+10/−20)/50 μm (+10/−20) by optimizing the opening ratio and thickness of the screen plate. A layer-forming technology developed for the radical capturing layer uses a two-fluid spraying method. Continuous formation of an 8 μm thick (±3 μm) radical capturing layer proved feasible by determining the appropriate slurry viscosity, spray head selection, and optimization of spraying conditions.

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