the performances of two-phase polymer-liquid pebax®/polyethylene glycol (peg) and three-phase polymer-liquid-solid pebax®/peg/mwnt thin film composite membranes for co2 and ch4 permeation were studied. the effect of temperature and mwnt/pebax® ratio on single gas (co2 and ch4) permeability was investigated. the permeation of both gases was measured at different temperatures from 303 to 323 ˚k. ...

In this study, a series of sulfonated hydrocarbon pentablock terpolymers (NEXAR® Polymers) with different ion exchange capacities (1.0, 1.5, and 2.0 meq g−1) were characterized investigated as membranes ionomers in hydrogen fuel cells. All NEXAR® Membranes exhibited higher proton conductivity (>0.2 S cm−1 at 80 °C, 90% RH) than Nafion (the most frequently used polymer membrane cells). The Membr...

asymmetrically mixed matrix matrimid-mil-53 membranes with silicone cover layer were fabricated. for better understanding of membrane fabrication process, three main parameters of fabrication, matrimid concentration, silicone concentration and weight percentage of metal organic framework (mil-53) particles, were optimized by an experimental design method. cross-section sem images were used to s...

Water management is one issue that must be surpassed to ensure high membrane proton conductivity and adequate reactant transport in the membrane-electrode assembly (MEA) simultaneously. A well-designed water system based on a comprehensive understanding of inner part polymer electrolyte (PEM) fuel cell. In this work, phenomena MEA PEM cell are analyzed by using mathematical model. The diluted s...

in the current work, graphene oxide (go) samples were prepared at room temperature from graphite flakes using a modified hummer's method to produce metal-free electrocatalysts. the effect of the duration of the oxidation process on the structural, chemical and physical characteristics of the go samples was evaluated using x-ray diffraction (xrd), fourier transform infrared spectroscopy (ftir), ...

cyanide ion, is an environmentally significant pollutant in many industrial wastewaters.therefore, a considerable number of methods have been studied for the wastewater treatment containingcyanide. the goal of our work consists in applying a simple and economic process for solving this problem ofpollution. the removal of cyanide ions by using three anion exchange membranes has been studied unde...

We are proposing a conceptual membrane electrode assembly (MEA) of proton exchange water electrolyzer that includes layer graphene oxide (GO) at the cathode side. This GO primarily reinforces MEA to allow operation higher pressure difference between and anode Additional benefits would be perfect prevent both hydrogen crossover thus for pure, dry escaping directly from without losses due crossov...

The application of organic-inorganic nanocomposite membranes allows for a synergy between the desirable thermal and mechanical properties inorganic materials with reactivity, dielectric properties, durability, flexibility, processability polymeric materials. Proton exchange membrane fuel cells (PEMFCs) suffer from some problems including water content management, carbon monoxide poisoning, hydr...

Proton exchange membranes (PEM) for a direct methanol fuel cell (DMFC) have main drawbacks which are methanol permeability, reduced proton conductivity and the cost of the membrane. This paper reviews different polymeric materials such as fluorinated, non-fluorinated, acid-base complex, and composite membranes for DMFC. Currently, nonfluorinated membranes gain a lot of atte...

New proton exchange membrane (PEM) materials with high proton conductivities at elevated temperatures (ca. > 150 °C) offer the promise of improving PEM fuel cell operation. Higher operating temperatures would provide several benefits including: (i) improved resistance to carbon monoxide poisoning of the platinum (Pt) electrocatalyst at the anode, (ii) reduced need for feed-stream heat and humid...