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Showing 1 to 20 of 50 for “"Proton Conductivity"”.
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High Temperature Polymers for Proton Exchange Membrane Fuel Cells
Novel proton exchange membranes (PEMs) were investigated that show potential for operating at higher temperatures in both direct methanol (DMFC) and H2/air PEM fuel cells. The need for thermally stable polymers immediately suggests the possibility of heterocyclic polymers bearing appropriate ion …
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Synthesis and characterization of purely sulphonated and composite membranes for high temperature fuel cells
… energy in an environmentally friendly method. Proton exchange membrane fuel cells (PEM-FCs) require a PEM for use, where the most accepted PEM used today is Nafion. Nafion is ideal due to its chemical durability and high proton conductivity however it is highly expensive and limited to 80˚C …
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Synthesis and characterisation of proton conducting composite materials resilient to dehydration at elevated temperatures
… any membrane that relies on water to transport protons will dehydrate and thus, the proton conductivity of the membrane will start to degrade. Here the development of a new proton conducting material that is resilient to dehydration is presented. The exploitation of the oxide surface of the ca. …
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Synthesis and Characterization of Multiblock Copolymers for Proton Exchange Membrane Fuel Cells (PEMFC)
… multiblock copolymers are promising proton exchange membrane (PEM) materials due to their ability to form various morphological structures which enhance transport. Four arylene chlorides monomers (2,5-Dichlorobenzophenone and its derivatives) were first successfully synthesized from …
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Synthesis and Characterization of Hydrophobic-Hydrophilic Multiblock Copolymers for Proton Exchange Membrane Applications
Proton exchange membrane fuel cells (PEMFCs) have been extensively studied as clean, sustainable and efficient power sources for electric vehicles, and portable and residential power sources. As one of the key components in PEMFC system, proton exchange membranes (PEMs) act as the electrolyte that …
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Characterization of Structure-Property Relationships in Hydrophilic-Hydrophobic Multiblock Copolymers for Use in Proton Exchange Membrane Fuel Cells
Proton exchange membrane fuels cells (PEMFCs) are one of the primary alternatives to internal combustion engines. The key component is the proton exchange membrane, or PEM, which should meet a number of requirements, including good proton conductivity under partially humidified conditions. A number …
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Polymeric and Polymer/Inorganic Composite Membranes for Proton Exchange Membrane Fuel Cells
Several types of novel proton exchange membranes which could be used for both direct methanol fuel cells (DMFCs) and hydrogen/air fuel cells were investigated in this work. One of the main challenges for DMFC membranes is high methanol crossover. Nafion, the current perfluorosulfonic acid copolymer …
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Synthesis and Characterization of Linear and Crosslinked Sulfonated Poly(arylene ether sulfone)s: Hydrocarbon-based Copolymers as Ion Conductive Membranes for Electrochemical Systems
… excellent mechanical strength, satisfactory conductivity, and excellent transport properties of water and ions. These copolymers can be used in a variety of topologies. Structure-property-performance relationships of these membranes as candidates for electrolysis of water for hydrogen …
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Synthesis and Characterization of Hydrophobic-Hydrophilic Multiblock Copolymers for Proton Exchange Membrane and Segmented Copolymer Precursors for Reverse Osmosis Applications
… for alternative materials used in the field of Proton Exchange Membrane Fuel Cells (PEMFCs) and Reverse Osmosis (RO) applications. In particular, wholly aromatic sulfonated poly(arylene ether sulfone)s are of considerable interest in the field of PEMFCs and RO, due to their affordability, high …
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Synthesis, crosslinking and characterization of disulfonated poly(arylene ether sulfone)s for application in reverse osmosis and proton exchange membranes
Novel proton exchange (PEM) and reverse osmosis (RO) membranes for application in fuel cell and water purification respectively were developed by synthesis and crosslinking of disulfonated biphenol-based poly (arylene ether sulfone)s (BPS). Crosslinking is a prospective option to reduce the water …
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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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Polymer electrolyte membranes for direct methanol fuel cells
This thesis study is aimed at producing proton-conducting polymer electrolyte membranes (PEMs) for direct methanol fuel cells (DMFCs). In this thesis, relatively inexpensive monomers, 2-acrylamido-2-methyl propanesulfonic acid (AMPS) and 3-sulfopropyl methacrylate (SPM) in particular, were deployed …
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Tailoring Perovskite- and Fluorite-Type Oxides for Solid Oxide Fuel Cells (SOFCs)
… was evaluated at 1000 ºC. The electrical conductivity of the reaction product Ce1-x-y-zRExZrYMozO2 in air and wet H2 was found to be lower than that of Ce0.7RE0.2Mo0.1O2, due to the formation of defect associates and a decrease in concentration of charge carriers. The effect of A-and …
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Nano-scale Glucose Fuel Cells for Energy Harvesting in the Human Body Based on Proton Conduction in Cerium Oxide
… glucose fuel cell to date. By use of the ceramic proton-conducting electrolyte ceria and a free-standing membrane device architecture, the novel ceramic-electrolyte glucose fuel cell can be scaled down to a thickness below 400 nm. The ceramic-electrolyte glucose fuel cell is biocompatible by …
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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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Chemical and Physical Modifications of Semicrystalline Gels to Achieve Controlled Heterogeneity
… have emerged as desirable candidates for proton exchange membranes (PEMs) due to their excellent mechanical properties, high thermal and chemical stability, and low cost. Specifically, sulfonated multiblock copolymers are attractive because their phase-separated morphologies aide in facile …
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Morphological and Structure-Property Analyses of Poly(arylene ether sulfone)-Based Random and Multiblock Copolymers for Fuel Cells
The commercialization of proton exchange membrane (PEM) fuel cells depends largely upon the development of PEMs whose properties are enhanced over current perfluorinated sulfonic acid PEMs. Understanding how a PEM's molecular weight and morphology affect its relevant performance properties is …
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The Influence of Aromatic Disulfonated Random and Block Copolymers' Molecular Weight, Composition,and Microstructure on the Properties of Proton Exchange Membranes for Fuel Cells
… the molecular weights, but water uptake and proton conductivities found insensitive to copolymers" molecular weights. Three series of disulfonated poly(arylene ether ketone) random copolymers have been synthesized and comparatively studied, according to their different chemical structures, …
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Synthesis and Characterization of Hydrophobic-Hydrophilic Segmented and Multiblock Copolymers for Proton Exchange Membrane and Reverse Osmosis Applications
… and multiblock copolymers for application as proton exchange membranes (PEMs) in fuel cells or as reverse osmosis (RO) membranes for water desalination. The first objective was to demonstrate that synthesizing blocky copolymers using a one oligomer, two monomer segmented copolymerization …
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Fundamental investigation of fuel cell-based breath alcohol sensors and the cause of sensor degradation in low-humidity conditions
… were investigated in this study. Loss of proton conductivity as a result of membrane dehydration was shown to be reversible by rehydrating the membrane in humid conditions. Loss of electrochemically active surface area of Pt is irreversible and seems to be caused by a change in sensor …
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