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

Nanomaterials ◽  
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.

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

2009 ◽  
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.

Simulation of carbon black aggregate and evaluation of ionomer structure on carbon in catalyst layer of polymer electrolyte fuel cell

2019 ◽  
Vol 439 ◽  
pp. 227060 ◽  
Author(s):  
Gen Inoue ◽  
Tomohiro Ohnishi ◽  
Magnus So ◽  
Kayoung Park ◽  
Masumi Ono ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Carbon Black ◽  
Polymer Electrolyte ◽  
Catalyst Layer ◽  
Polymer Electrolyte Fuel Cell

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

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 899
Author(s):  
Yushi Tamaki ◽  
Kimihiko Sugiura
Keyword(s):  
Layer Structure ◽  
Mixing Layer ◽  
Phase Interface ◽  
Single Layer ◽  
Catalyst Layer ◽  
Polymer Electrolyte Fuel Cell ◽  
Membrane Electrode ◽  
Electrode Area ◽  
Three Phase ◽  
Electrode Assemblies

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.

Development and Application of a Sample Holder for In Situ Gaseous TEM Studies of Membrane Electrode Assemblies for Polymer Electrolyte Fuel Cells

2017 ◽  
Vol 23 (5) ◽  
pp. 945-950 ◽  
Author(s):  
Takeo Kamino ◽  
Toshie Yaguchi ◽  
Takahiro Shimizu
Keyword(s):  
Fuel Cells ◽  
Polymer Electrolyte ◽  
Structural Changes ◽  
Membrane Electrode Assembly ◽  
Polymer Electrolyte Fuel Cells ◽  
Polymer Electrolyte Fuel Cell ◽  
Membrane Electrode ◽  
Sample Holder ◽  
Electrode Assemblies

AbstractPolymer electrolyte fuel cells hold great potential for stationary and mobile applications due to high power density and low operating temperature. However, the structural changes during electrochemical reactions are not well understood. In this article, we detail the development of the sample holder equipped with gas injectors and electric conductors and its application to a membrane electrode assembly of a polymer electrolyte fuel cell. Hydrogen and oxygen gases were simultaneously sprayed on the surfaces of the anode and cathode catalysts of the membrane electrode assembly sample, respectively, and observation of the structural changes in the catalysts were simultaneously carried out along with measurement of the generated voltages.

Sign in / Sign up

Export Citation Format

Share Document