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Showing 1 to 20 of 43 for “"Nafion®"”.
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Ru,Rh,Ru Supramolecular Photocatalysts within Nafion® Membranes: Ion-exchange, Photoelectrolysis and Electron Transfer Processes
Perfluorosulfonate ionomers, such as Nafion® have been shown to demonstrate a profound affinity for large cationic complexes, and the study of polymer-bound cations may provide insight regarding Nafion® morphology by contrasting molecular size with existing models. The trimetallic complex, …
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Morphological and Mechanical Properties of Dispersion-Cast and Extruded Nafion Membranes Subjected to Thermal and Chemical Treatments
… properties of both extruded and dispersion-cast Nafion® membranes. The project can be divided into three primary objectives; obtaining a fundamental understanding of the glass transition temperature of Nafion®, determining the effect of thermal annealing treatments on the morphology and …
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Comparative analysis of Polymer Electrolyte Membrane (PEM) fuel cells
… basic types, which are the Long-Side-Chain (LSC) Nafion® and the ShortSide-Chain (SSC) Aquivion® ionomer MEA with emphasis on performance and durability which are currently not well understood. In particular, electrochemical circuit models and semiempirical models were employed to enable …
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The Effects of Structure, Humidity and Aging on the Mechanical Properties of Polymeric Ionomers for Fuel Cell Applications
… humidity and aging on the mechanical behavior of Nafion® and Dais® ionomers. It was determined that the majority of the properties of these membranes were controlled by the formation and growth of the ionic clusters that were the direct result of the ionic nature of these materials. In the process …
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Modifications and studies of the anode catalyst layer for the direct formic acid fuel cell
… The first is the study of the effect of Nafion® loading in the anode catalyst layer using electrochemical techniques. Nafion®, within the anode and cathode catalyst layers, plays a large role in the performance of fuel cells. Nafion® also serves as a binder to help hold the catalyst …
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Rational design of proton exchange membranes: perfluoro polymers with sulfonic acid and heteropoly acid functionalities
… 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 driven by an industry need for a proton exchange membrane material which performs at …
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Water transport in fuel cell membranes measured by laser interferometry
… to explain the transport of water within Nafion® membranes, but also provided useful information to describe and understand the water transport mechanism in Nafion® membranes. Finally, the application of the laser interferometry to the membranes within a fuel cell has demonstrated the …
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Multiscale modelling of CO₂ Electroreduction on Cu - based gas diffusion electrodes (GDEs)
… Cu catalyst-ionomer interaction is investigated. Nafion®, a perfluorosulfonate ionomer, has been proposed in literature, as a shielding material against homogeneous bicarbonates reaction. Due to the residing negative sulfonate ions which deprotonates in water, Nafion® is able to repel the negative …
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Understanding the carbon morphology in sulfonated-silica ceramic carbon electrodes for the PEM fuel cell device
… be attributed to the perfluorosulfonated ionomer Nafion®, that is commercially available and used as a binder within the catalyst layer. The high cost and poor durability of current fuel cell catalyst layers has been linked to the use of Nafion® and the amount of carbon in the catalyst. In this …
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Ion Conducting Polyelectrolytes in Conductive Network Composites and Humidity Sensing Applications for Ionic Polymer-Metal Composite Actuators
… acid) (PAMPS) and Nafion® were incorporated into an ISAM CNC film with poly(allylamine hydrochloride) (PAH) and anionic gold nanoparticles actuators to further improve bending. CNC films were optimized for bending through pH adjustments in PAH and adding NaCl to the …
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Development of an EQCM-based sensor for metal ions
… of a gold (Au) piezoelectrode modified by a Nafion® polymer layer impregnated with a cationic hydroxainic acid (HA), a ligand showing oxidation state specific selectivity towards actinide 4+ ions and a non-radioactive demonstrator ion, Fe3+ In its final configuration, the polymer layer will …
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Transport properties of anion exchange membranes for fuel cell applications
… proton exchange membranes (PEM), such as Nafion® are highly conductive and chemically and mechanically stable, PEMs are not widely used in fuel cells due to the higher cost of fluoropolymers and the platinum metal catalysts. Anion exchange membranes (AEM) offer lower cost of both polymers …
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Caractérisation d'un champ de forces pour les membranes échangeuses de protons
… est la simulation d'une PEM de référence, le Nafion®, à différents niveaux d'approximation de calcul dans le but de guider la synthèse de nouvelles membranes plus performantes. Le but de l'étude présenté dans ce mémoire a été la caractérisation du groupement fonctionnel acide de la chaîne …
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Synthesis and Characterization of Hydrophobic-Hydrophilic Multiblock Copolymers for Proton Exchange Membrane Applications
… ionomers (PFSAs), represented by DuPont's Nafion®. Despite their good chemical stability and proton conductivity at high relative humidity (RH) and low temperature, several major drawbacks have been observed on PFSAs, such as high cost, high fuel permeability, insufficient thermo-mechanical …
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High Temperature Polymers for Proton Exchange Membrane Fuel Cells
… at 80 C compared to the state-of-the-art PEM (Nafion®); nevertheless these membranes became brittle under operating conditions. Several series of poly(arylene ether)s based on disodium-3,3′-disulfonate-4,4′-dichlorodiphenylsulfone (S-DCDPS) and a benzimidazole-containing bisphenol were …
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Controlling the mechanical and transport properties of layer-by-layer films and electrospun mat composite membranes for fuel cell applications
… fuel cells, the current industrial standard PEM, Nafion®, does not have all the required attributes. Layer-by-Layer (LbL) assembly allows for the controlled deposition of alternating polyelectrolytes at the nanometer scale. This technique can be used with highly proton conductive water soluble …
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The Formation of Metal Nanoparticle-Carbon Nanotube Composite Materials for the Non-enzymatic Detection of Glucose
… sensitivity. These films were combined with a Nafion® membrane to improve selectivity towards glucose in the presence of commonly occurring interferants. The fMWCNT-Aunano(NaBH4) composite was also combined with palladium nanoparticles (PdNPs) to form a composite named fMWCNT-Aunano/Pdnano. …
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Understanding of Ammonia Transport In Pem Fuel Cells
… ERE was developed for PEM fuel cell by using a Nafion® strip and used to understand contamination mechanism. The voltage of anode electrode relative to ERE was measured during a polarization curve. The data showed the measurement of individual electrode was extremely affected by the misalignment …
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Studies Toward the Development of a Microelectrode Array for Detection of Dopamine Through Redox Cycling
… the involvement of polymer coating such as Nafion®.</p> <p>Microfabrication was used to produce different geometries (parallel bands and concentric rings) with feature size of 4 µm or 25 µm and inter-electrode spacing of 4 µm or 25 µm on a single substrate (microelectrode arrays). Comparison …
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Experimental Studies on the Mechanical Durability of Proton Exchange Membranes
… because of the controllable mechanical loading. Nafion® NRE-211 membrane was tested at three different temperatures and the time-temperature superposition principle was used to construct a stress-lifetime master curve. Tested at 90°C, extruded Ion Power® N111-IP membrane was found to have longer …
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