Surface Properties of PEMFC Gas Diffusion Layers
- Los Alamos National Laboratory (LANL)
- Augustine Scientific
The wetting properties of PEMFC Gas Diffusion Layers (GDLs) were quantified by surface characterization measurements and modeling of material properties. Single-fiber contact-angle and surface energy (both Zisman and Owens-Wendt) data of a wide spectrum of GDL types is presented to delineate the effects of hydrophobic post-processing treatments. Modeling of the basic sessile-drop contact angle demonstrates that this value only gives a fraction of the total picture of interfacial wetting physics. Polar forces are shown to contribute 10-20 less than dispersive forces to the composite wetting of GDLs. Internal water contact angles obtained from Owens-Wendt analysis were measured at 13-19 higher than their single-fiber counterparts. An inverse relationship was found between internal contact angle and both Owens-Wendt surface energy and % polarity of the GDL. The most sophisticated PEMFC mathematical models use either experimentally measured capillary pressures or the standard Young-Laplace capillary-pressure equation. Based on the results of the Owens-Wendt analysis, an advancement to the Young-Laplace equation is proposed for use in these mathematical models, which utilizes only solid surface energies and fractional surface coverage of fluoropolymer. Capillary constants for the spectrum of analyzed GDLs are presented for the same purpose.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- DOE Contract Number:
- DE-AC05-00OR22725
- OSTI ID:
- 1023342
- Journal Information:
- Journal of the Electrochemical Society, Vol. 157, Issue 2; ISSN 0013-4651
- Country of Publication:
- United States
- Language:
- English
Similar Records
A Study on Surface Texture and Wettability of Femtosecond Laser Treated Aluminum Alloys
Fundamentals of wetting and spreading with emphasis on soldering
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
DIFFUSION
MATHEMATICAL MODELS
PHYSICS
SIMULATION
SURFACE ENERGY
SURFACE PROPERTIES
WATER
Gas Diffusion Layer
Surface Energy Measurement
Heterogeneous Contact Angle
Single-Fiber Contact Angle
Internal Water Contact Angle
Surface Polarity
Heterogeneous Wetting