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Showing 1 to 20 of 48 for “"Proton Exchange Membranes"”.
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Structure Property Relationships of Proton Exchange Membranes
… reported in the literature show reduced proton conductivity at low water content. This was attributed to the formation of an isolated morphology. Over the last few years our group has synthesized thermally stable multiblock copolymers with varying chemical structures and compositions. …
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Gas Transport In Two-Layer Proton Exchange Membranes
… SO2 transport supported on a membrane with high proton conductivity. However, it is difficult to measure the properties of the LPAP film since this layer is not free standing. Hence, we have developed a model that allows us to obtain the gas transport properties (i.e., diffusion coefficient and …
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Transport and Structure in Fuel Cell Proton Exchange Membranes
… cells, Nafion, were compared. Species transport (protons, methanol, water) in hydrated membranes was found to correspond with the water-self diffusion coefficient as measured by pulsed field gradient nuclear magnetic resonance (PFG NMR), which was used as a measure of the state of absorbed water …
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Experimental Studies on the Mechanical Durability of Proton Exchange Membranes
… that affect the mechanical durability of proton exchange membranes (PEMs). The first two methods involved measuring the in-plane biaxial strength of PEMs and the biaxial hygrothermal stresses that occur in PEMs during hygrothermal cycles. The third method investigated the nonuniform …
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Gas Transport in Proton Exchange Membranes for use in Fuel Cell Applications
… were to study the gas transport properties of proton exchange membranes (PEM), namely disulfonated poly(arylene ether sulfone) (BPSH-35), post sulfonated diels-alder poly(phenylene) (SDAPP), and poly(perfluoro sulfonic acid) (Nafion). The O2 gas permeabilities were found to be lower in BPSH and …
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Polymer/nano-organic composite proton exchange membranes for direct methanol fuel cell application
The proton exchange membrane is one key component of direct methanol fuel cells, which has double functions of conducting protons, separating fuels and oxidant. At present, the performance and price of sulfonic acid proton exchange membrane used in direct methanol fuel cells are deeply concerned. …
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Development of novel catalysts coated non-fluorinated proton exchange membranes for water electrolysis
… sources. Among the various electrolysis methods, proton exchange membrane water electrolysis (PEMWE) is particularly nota-ble for its high current density, efficient electrocatalysts, low gas crossover rates, and its ability to function across a broad range of power inputs. Major progress has been …
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Novel Polyphenylquinoxaline and Polybenzimidazole Proton Exchange Membranes For High Temperature Fuel Cell Systems
<p>Proton exchange membrane fuel cells (PEMFCs) have recently been acknowledged as one of the most promising alternative power sources due to their clean and efficient operation, as well as their numerous applications in transportation, stationary, cogeneration, and portable systems. High …
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Synthesis and Characterization of Sulfonated Polyimides as Proton Exchange Membranes for Fuel Cells
… stable ion conducting polymers (ICP) suitable as proton exchange membranes, PEM, for fuel cells. The candidate ICP's have been synthesized and characterized for molecular weight, chemical composition, film forming properties, thermal transition behavior, boiling water stability, solvent solubility …
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Characterization and modification of electrospun fiber mats for use in composite proton exchange membranes
… junctions between fibers. A mechanically robust proton exchange membrane with high ionic conductivity and selectivity is an important component in many electrochemical energy devices such as fuel cells, batteries, and photovoltaics. The ability to control and improve independently the mechanical …
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Rational design of proton exchange membranes: perfluoro polymers with sulfonic acid and heteropoly acid functionalities
… the field of perfluorinated sulfonic acid (PFSA) membranes is dictated by our understanding of pure PFSA ionomer materials like Nafion®, which performs well at saturated conditions but fails at low relative humidity and high operating temperatures (80-120 C). The motivation of this study is …
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Solution-casting of Disulfonated Poly(arylene ether sulfone) Multiblock Copolymer Films for Proton Exchange Membranes
… based, is to develop a novel hydrocarbon-based proton exchange membrane (PEM) material that can produce a proton conductivity of 0.1 S/cm at the operating conditions of 50 % relative humidity and 120 oC, which is the performance target set by the U.S. DOE for automotive application. As a part of …
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Synthesis and Characterization of Multiblock Copolymer Proton Exchange Membranes for High Temperature Fuel Cell Applications
The potential success of a proton exchange membrane (PEM) fuel cell as an alternative energy source depends highly upon the development of high performance PEMs. Typically, state-of-the-art PEMs have been perfluorinated sulfonated ionomer membranes such as Nafion® by DuPont. Although these …
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Measuring Material Properties of Proton Exchange Membranes using Pressure Loaded Blister Testing and Digital Image Correlation
The strength and durability of proton exchange membranes for use in fuel cells has received much attention recently due to the increased push for sustainable alternatives to the internal combustion engine. To be viable, these alternatives must have comparable lifetimes and power outputs to the …
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Analysis and Modeling of the Mechanical Durability of Proton Exchange Membranes Using Pressure-Loaded Blister Tests
… significant biaxial stresses in the constrained proton exchange membranes (PEM). The PEM's ability to withstand cyclic environment-induced stresses plays an important role in membrane integrity and consequently, fuel cell durability. In this thesis, pressure loaded blister tests are used to study …
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Linear and Nonlinear Viscoelastic Characterization of Proton Exchange Membranes and Stress Modeling for Fuel Cell Applications
… on the viscoelastic and fracture properties of proton exchange membranes (PEM) used in fuel cell applications was studied. Understanding and accurately modeling the linear and nonlinear viscoelastic constitutive properties of a PEM are important for making hygrothermal stress predictions in the …
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Theory of proton exchange membranes fuel cells and the testing of performance characteristics of polymer electrolyte membranes
Proton exchange membrane (PEM) fuel cells hold great promise as source of power. A hydrogen and oxygen PEM fuel is a simple fuel cell that can be theoretically characterized. The performance of a PEM fuel cell can be characterized if the contents of the two gas lines are known, the back pressure is …
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Mechanics of proton exchange membranes : time, temperature, and hydration dependence of the stress-strain behavior of persulfonated polytetrafluorethylene
… and greenhouse gasses become more of a concern. Proton Exchange Membrane Fuel Cells (PEMFC), in which protons from hydrogen gas are passed across a membrane to react with oxygen gas producing electricity, with water as the only waste product, are a cleaner and potentially more efficient chemical …
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