Catalysts for Polymer Membrane Fuel Cells

Low-temperature fuel cells with a polymer membrane electrolyte are at an exciting time in their development [...]

Increasing the efficiency Proton exchange membrane (PEMFC) & other fuel cells through multi graphene layers including polymer membrane electrolyte

Multi layers Graphene has been simulated theoretically for hydrogen storage and oxygen diffusion at a single unit of fuel cell. Ion transport rate of DFAFC, PAFC, AFC, PEMFC, DMFC and SOFC fuel cells have been studied. AFC which uses an aqueous alkaline electrolyte is suitable for temperature below 90 degree and is appropriate for higher current applications, while PEMFC is suitable for lower temperature compared to others. Thermodynamic equations have been investigated for those fuel cells in viewpoint of voltage output data. Effects of operating data including temperature (T), pressure (P), proton exchange membrane water content (λ) , and proton exchange membrane thickness on the optimal performance of the irreversible fuel cells have been studied.Obviously, the efficiency of PEMFC extremely related to amount of the H2 concentration, water activities in catalyst substrates and polymer of electrolyte membranes, temperature, and such variables dependence in the direction of the fuel and air streams.

New Polymer Assembles with Potential Use as Solid Electrolytes Type Membranes

Solid polymer electrolyte (SPE) membranes with varying composition ratios were prepared from poly(vinyl alcohol) (PVA), poly(acrylic acid) (PAA) and poly(metacrylic acid) (PMMA). The acrylic acid monomer with cross-linker was first blended with PVA polymer. A free radical polymerization was then carried out to form an alkaline polymer electrolyte. The solution casting method was used to form the solid polymer membranes. The solid polymer membranes were characterized by FT-IR spectroscopy, SEM morphology analysis and electrochemical impedance spectroscopy. The results showed that at room temperature the highest ionic conductivity for the PVA/PAA/KOH solid polymer membrane electrolyte system was 4.54·10-8Ω-1cm-1. The PVA/PAA polymer membrane had good mechanical strength and ductility and would be a suitable polymer membrane electrolyte for the alkaline batteries and other electrochemical systems.