Degradation Characteristics of Electrospun Gas Diffusion Layers with Custom Pore Structures for Polymer Electrolyte Membrane Fuel Cells
Balakrishnan M, Shrestha P, Lee C, Ge N, Fahy KF, Messerschmidt M, Scholta J, Eifert L, Maibach J, Zeis R, Hatton BD, Bazylak A (2021)
Publication Type: Journal article
Publication year: 2021
Journal
Book Volume: 13
Pages Range: 2414-2427
Journal Issue: 2
Abstract
Electrospinning has been demonstrated to be a versatile technique for producing hydrophobic gas diffusion layers (GDLs) with customized pore structures for the enhanced performance of polymer electrolyte membrane (PEM) fuel cells. However, the degradation characteristics of custom hydrophobic electrospun GDLs (eGDLs) have not yet been explored. Here, for the first time, we investigate the degradation characteristics of custom hydrophobic eGDLs via an ex situ accelerated degradation protocol using H2O2. The surface contact angle of degraded eGDLs (44 ± 12°) was lower than that of pristine eGDLs (137 ± 6°). The loss of hydrophobicity was attributed to the degradation (via hydrolysis) of the fluorinated monolayers (formed via a direct fluorination treatment) on the electrospun carbon fiber surfaces as evidenced by the reduction in surface fluorine content. Degradation of the surface monolayers affected fuel cell performance under multiple operating conditions. At 100% relative humidity (RH), the loss of monolayers led to higher liquid water content and lower cell voltages compared to the pristine eGDL. At 50% RH, the degraded eGDL led to lower cell voltages due to the lower electrical conductivity of the degraded materials. The lower electrical conductivity was attributed to the oxidation of carbon fibers upon loss of the monolayers. Our results indicate the importance of designing robust hydrophobic surface treatments for the advancement of customized GDLs for effective long-term fuel cell operation.
Authors with CRIS profile
Involved external institutions
University of Toronto
Canada (CA)
Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW)
Germany (DE)
Helmholtz Institut Ulm
Germany (DE)
Karlsruhe Institute of Technology (KIT)
Germany (DE)
Canada (CA)
Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW)
Germany (DE)
Helmholtz Institut Ulm
Germany (DE)
Karlsruhe Institute of Technology (KIT)
Germany (DE)
How to cite
APA:
Balakrishnan, M., Shrestha, P., Lee, C., Ge, N., Fahy, K.F., Messerschmidt, M.,... Bazylak, A. (2021). Degradation Characteristics of Electrospun Gas Diffusion Layers with Custom Pore Structures for Polymer Electrolyte Membrane Fuel Cells. ACS Applied Materials and Interfaces, 13(2), 2414-2427. https://doi.org/10.1021/acsami.0c15324
MLA:
Balakrishnan, Manojkumar, et al. "Degradation Characteristics of Electrospun Gas Diffusion Layers with Custom Pore Structures for Polymer Electrolyte Membrane Fuel Cells." ACS Applied Materials and Interfaces 13.2 (2021): 2414-2427.
BibTeX: Download