Polymer electrolyte membrane fuel cell microscopy

Recently, taking advantage of the very narrow size distribution of the metal particles obtained, microemulsion has been used to prepare electrocatalysts for polymer electrolyte membrane fuel cells (PEMFCs) Catalysts containing 40 % Pt Ru (1 1) and 40% Pt Pd (1 1) on charcoal were prepared by mixing aqueous solutions of chloroplatinic acid, ruthenium chloride and palladium chloride with Berol 050 as surfactant in iso-octane. Reduction of the metal salts was complete after addition of hydrazine. In order to support the particles, the microemulsion was destabilised with tetrahydrofurane in the presence of charcoal. Both isolated particles in the range of 2-5 nm and aggregates of about 20 nm were detected by transmission electron microscopy. The electrochemical performance of membrane electrode assemblies, MEAs, prepared using this catalyst was comparable to that of the MEAs prepared with a commercial catalyst. 

K.W. Feindel, S.H. Bergens, R.E. Wasybshen, The influence of membrane electrode assembly water content on the performance of a polymer electrolyte membrane fuel cell as investigated by NMR microscopy, Phys. Chem. Chem. Phys. 9 (2007) 1850-1857. 

Scheiba, E, Benker, N., Kunza, U., Rotha, C. Fuess H. Electron microscopy techniques for the analysis of the polymer electrolyte distribution in proton exchange membrane fuel-cells. J. Power Sources 111 (2008), pp. 273-280. 

Magnetic Resonance Imaging (MRI) becomes one of the useful microscopy and is used not only for the medical purposes but also for chemical applications. For polyurethane foams, the analysis of the distributions of many microstructural features, including strut length and window and cell shape distributions, were carried out. The diffusion behaviours of water in membrane is investigated by MRI in order to develop the polymer electrolyte fuel cells.The solvent diffusions and the swollen behaviors were investigated by MRI for hydroxy methyl cellulose,high amylose starch tablets, poly(ethylene methacrylate)/poly(2-hydroxyethyl methacrylate)-co-tetrahydro-... 

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