The performance of a direct methanol alkaline anion-exchange membrane (Fumatech FAA3) fuel cell with Pt-free nitrogen-doped few-walled carbon nanotubes (N-FWCNT) as the cathode catalyst is compared with a commercial supported Pt catalyst. The ionomer content of the N-FWCNT cathode catalyst layer is therefore optimized and it is shown to be 40 wt% of FAA3. Scanning electron microscopy images of ...

In polymer electrolyte membrane fuel cells (PEMFCs), because the reaction rate in the cathode is slower than that in the anode, the cathode catalyst layers require more catalyst loading than the anodes [1]. Much research has been focused on improving the catalytic activity in cathodes and simultaneously reducing the amount of Pt supported by carbon black, which is the most commonly used cathode...

the produced liquid water in cathode catalyst layer (ccl) has significant effect on the operation of proton exchange membrane fuel cell (pemfc). to investigate this effect, the transport of oxygen in ccl in the presence of immiscible liquid water is studied applying a two-dimensional pore scale model. the ccl was reconstructed as an agglomerated system. to explore the wettability effects, diffe...

A low cost poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) phase inversion coating was developed as a cathode diffusion layer to enhance the performance of microbial fuel cells (MFCs). A maximum power density of 1430 ± 90 mWm 2 was achieved at a PVDF-HFP loading of 4.4 mg cm 2 (4:1 polymer:carbon black), with activated carbon as the oxygen reduction cathode catalyst. This power dens...

Oxygen transport across the cathode gas diffusion layer (GDL) in polymer electrolyte membrane (PEM) fuel cells was examined by varying the O2/N2 ratio and by varying the area of the GDL extending laterally from the gas flow channel under the bipolar plate (under the land). As the cathode is depleted of oxygen, the current density becomes limited by oxygen transport across the GDL. Oxygen deplet...

In this article, a two dimensional pore scale model of polymeric fuel cell, which is promising of a clean and renewable energy production, is presented here. Let reactive gases behave as an ideal gas; inhomogeneous anisotropic structure of the gas diffusion layer, is contemplated as a random generated circular porous media. Lattice Boltzmann method is applied to inquire the fluid flow and mass ...

The performance of polymer electrolyte membrane (PEM) fuel cell is mainly influenced by ohmic, activation, and concentration overpotentials. Ohmic overpotential is directly proportional to electric resistance in the fuel cell components that can be estimated from the experimental data or from the empirical relation for the cell polarization curve. However, such simple relation is not available ...

There are several obstacles to the commercialization of PEM fuel cells.  One of the reasons is that the presence of carbon monoxide (CO) in the reformatted fuel, even at a very small scale, decreases the fuel cell performance. The aim of this paper is to investigate the effect of CO in reformatted fuel on PEM fuel cell performance. For this purpose, a steady state, one-dimensional and non-isoth...

A model for the simulation of the steady-state impedance response of a polymer electrolyte membrane fuel cell ~PEMFC! cathode is presented. The catalyst layer of the electrode is assumed to consist of many flooded spherical agglomerate particles surrounded by a small volume fraction of gas pores. Stefan-Maxwell equations are used to describe the multicomponent gas-phase transport occurring in b...