It is important to have accurate, reliable, and convenient techniques for determining the methanol crossover rate through the polymer electrolyte membranes of fuel cells. In this work, various electrochemical techniques, namely; cyclic voltammetry, chronoamperometry and potentiometry, have been used to measure the methanol crossover rates using Nafion 117 membrane. The purpose of using differen...

We present a detailed analysis of the nanostructure of the short side chain (SSC) perfluorosulfonic acid membrane and its effect on H(2)O clustering, H(3)O(+) and H(2)O diffusion, and mean residence times of H(2)O near SO(3)(-) groups based on molecular dynamics simulations. We studied a range of hydration levels (λ) at temperatures of 300 and 360 K, and compare the results to our findings in t...

The complex environments experienced by water molecules in the hydrophilic channels of Nafion membranes are studied by ultrafast infrared pump-probe spectroscopy. A wavelength dependent study of the vibrational lifetime of the O-D stretch of dilute HOD in H(2)O confined in Nafion membranes provides evidence of two distinct ensembles of water molecules. While only two ensembles are present at ea...

Progress Report and Future Directions The fuel cell research cluster began with the DOE EPSCoR implementation grant “Fuel Cells: A Mobile Energy Source for the 21 Century” in July of 2001. The focus of this research was developing new and improved materials for hydrogen production and PEM fuel cells. Building on the major successes of this project, we proposed and were granted a renewed impleme...

Ionic polymer-metal composites ~IPMCs! consist of a polyelectrolyte membrane ~usually, Nafion or Flemion! plated on both faces by a noble metal, and is neutralized with certain counter ions that balance the electrical charge of the anions covalently fixed to the backbone membrane. In the hydrated state ~or in the presence of other suitable solvents!, the composite is a soft actuator and sensor....

We describe a novel and simple mechanism for inducing ion concentration polarization (ICP) using a surface-patterned perm-selective nanoporous film like Nafion in single, open microchannels. Such a surface-patterned Nafion film can rapidly transport only cations from the anodic side to the cathodic side through the nanopore clusters so that it is possible to generate an ICP phenomenon near the ...

A helicon plasma sputtering system is used to deposit small amounts of platinum on microporous carbon support composed of Vulcan XC 72 carbon particles (known as gas diffusion layer GDL) to form Pt catalysed electrodes for proton exchange membrane fuel cells (PEMFC). Electrodes with low Pt loading are prepared, assembled in custom-made membrane electrode assemblies (MEAs) and tested for the hyd...

The use of thinner membranes in polymer electrolyte water electrolysis increases the likelihood forming an explosive H 2 /O mixture anode stream. Doping Pt nanoparticles into a Nafion membrane as recombination catalyst effectively lowers hydrogen crossover. Here, we propose additional co-doping cerium-zirconium oxide radical scavenger to mitigate degradation. Our results show over 4-fold reduct...