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The effect of chloride as catalyst layer contaminant on the degradation of PEMFCs

In this work, the effect of chloride as a catalyst contaminant was studied on the performance and durability of a low power open-cathode fuel cell, intended for passive management of water. In an ex-situ study, cyclic voltammetry was used to assess the redox behaviour of platinum in chloride contaminated solutions at room temperature.The cell was operated integrating a range of relative humidity (RH) from ~30 t...

Characterization of MEA degradation for an open air cathode PEM fuel cell

As fuel cell technology matures and time scale to commercialization decreases, the need for a more comprehensive knowledge of materials’ aging mechanisms is essential to attain specified lifetime requirements for applications. In this work, the membrane electrode assembly (MEA) degradation of an eight-cell PEM low power stack was evaluated, during and after fuel cell aging in specified testing conditions of loa...

Platinum instability in PEM fuel cells MEA’s subjected to chloride contamination

In this work a low power fuel cell, intended for passive management of water, was operated integrating a range of relative humidity (RH) from ~30 to 80% and temperatures from 5 to 55 ºC. The stack was fed with pure hydrogen. An open air cathode was designed for easy water removal and stack cooling. The stack uses own design flow field drawn on graphite plates from Schunk and a commercial MEA with carbon support...

MEA degradation in PEM Fuel Cell : a joint SEM and TEM study

One of the important factors determining the lifetime of polymer electrolyte membrane fuel cells (PEMFCs) is membrane electrode assembly (MEA) degradation and failure. The lack of effective mitigation methods is largely due to the currently very limited understanding of the underlying mechanisms for mechanical and chemical degradations of fuel cell MEAs. This work reports on the effect of 1500 h operation of an...

Materials degradation mechanisms in an open cathode low power PEM Fuel Cell

In this work, a low power PEM fuel cell intended for passive management of water was operated integrating a range of relative humidity (RH) from 30 to 80% and temperatures from 5 to 55ºC. An open air cathode, provided with an excess air stoichiometry condition, was designed for easy water removal and stack cooling. The 4 cell stack was fed with pure hydrogen and uses own design flow field drawn on graphite plat...

Hydrogen production from sodium borohydride on a Ni-Ru catalyst : an electroche...

Previous work by the authors has demonstrated a high rate and high yield hydrolysis of sodium borohydride, in the presence of a Ni-Ru catalyst synthesized by wet chemistry. The catalyst has been fully characterized and utilized more than 300 times exhibiting high stability and durability. In this work, results of an electrochemical study are reported using the powder catalyst supported on a Ni foam in order to ...

Electronic properties of Al-Nb mixed oxide as a function of their composition