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Showing 1 to 20 of 22 for “"polymer electrolyte membrane fuel cells"”.
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Condition monitoring of polymer electrolyte membrane fuel cells
… some of the limitations inherent in batteries, fuel cell based power generators and converters have been developed. Fuel cells act as electrochemical energy converters that convert a fuel source such as natural gas directly into electrical power without any secondary phases. For systems running …
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Carbon nanotube supported electrocatalysts for polymer electrolyte membrane fuel cells
"Fuel cells are promising alternative power generating devices that can provide clean and environmentally friendly energy for the ever growing global energy demand. This this research was aimed at a study of novel electrocatalysts for polymer electrolyte membrane (PEM) fuel cells. Carbon nanotubes …
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Impedance spectroscopy techniques for condition monitoring of polymer electrolyte membrane fuel cells
… recently, quality, continues to increase. The fuel cell presents itself as a promising prospect to solve one of mankind’s current challenge - clean energy. The fuel cell is essentially an electrochemical conversion system which takes in fuel supply to produce electricity. Some key features make …
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MULTISCALE COMPUTATIONAL MODELING OF NANOSTRUCTURE AND TRANSPORT IN POLYMER ELECTROLYTE MEMBRANE FUEL CELLS
Polymer electrolyte membrane fuel cells (PEMFCs) are predicted to revolutionize energy conversion for transportation due to a multitude of advantages over conventional methods. However, due to their lack of resillience to adverse conditions, they are not as widespread as other portable energy …
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Low PGM PtCo alloy catalysts for low loading Polymer Electrolyte Membrane Fuel Cells
Polymer Electrolyte Membrane Fuel Cells (PEMFCs) are a promising means of generating clean energy in especially transportation applications. The electrochemical conversion of energy is driven within membrane electrode assemblies (MEAs) over costly Pt catalyst which limits PEMFC cost viability. PtCo …
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Using polymer electrolyte membrane fuel cells in a hybrid surface ship propulsion plant to increase fuel efficiency
… to lower the amount of money spent purchasing fuel. Operational restrictions limiting fuel use are temporary and cannot be dependably relied upon. Long term technical research toward improving fuel efficiency is ongoing and includes advanced gas turbines and integrated electric propulsion …
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A comprehensive fractal approach in determination of the effective thermal conductivity of gas diffusion layers in polymer electrolyte membrane fuel cells
The challenges in the fuel cell industry is to produce the efficient thermal and water management for accurate determination of the effectiveness thermal conductivity of gas diffusion layers (GDL) used in polymer electrolyte membrane fuel cells (PEMFC‟s). This is one of the factors affecting the …
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Materials For Energy: Complex Oxides And Nitrides For New Polymer Electrolyte Membrane Fuel Cell Catalysts And Supports
… currently used carbon-based catalyst supports in polymer electrolyte membrane fuel cells (PEMFC) are not sufficiently stable. New, non-carbon catalyst supports are required for large-scale commercialization of PEMFCS, and must be stable in low pH (1-2) and up to +1.5 V (vs. SHE). The material also …
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Analysis of a duo-selecting membrane reactor for the water-gas shift
… hydrocarbons to produce hydrogen suitable for fuel cells; carbon monoxide poisons the low temperature fuel cells (phosphoric acid and polymer electrolyte membrane fuel cells) and must therefore be removed. The reaction is limited by thermodynamic equilibrium at higher temperatures, while …
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Microscopic and spectroscopic characterization of fuel cell catalyst layer materials and interfaces
Polymer electrolyte membrane fuel cells (PEMFCs) are a central technology for the decarbonization of the heavy-duty transportation sector and of industrial processes. This thesis is focused on detailed electron microscopy and x-ray spectroscopy characterization of composition and morphology of …
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Investigation of the Colloidal Behaviour of Carbon Black and Perfluorosulfonated Ionomer in Various Solvents
… microstructure model of catalyst layer of polymer electrolyte membrane fuel cells. Ionomer aggregation behaviour in solution was investigated at different ionomer concentration, solvent type and solvent composition. Ionomer was found to exist in three forms in solution. Extended molecule …
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Multimetallic Nanoparticles For Fuel Cell Electrocatalysts: Considerations Of Their Formation And Thin-Film Inspired Compositions
… efforts to develop new materials for use in polymer electrolyte membrane fuel cells, techniques for the high throughput synthesis and evaluation of thin films have been developed. These studies have revealed several multimetallic systems (both disordered alloys and ordered intermetallics) …
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Water-gas shift conversion in microchannel reactors using noble metal catalysts
Fuel cell technology will play a crucial role in future sustainable energy generation. Different types of fuel cells had been developed, of which Polymer Electrolyte Membrane Fuel Cells (PEMFCs) are the fuel cells of choice for small scale stationary and mobile applications that operate under …
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Comparative analysis of Polymer Electrolyte Membrane (PEM) fuel cells
… out as the preferable ionomers for making the Polymer Electrolyte Membrane Fuel Cells (PEMFC) membranes owing to their extensive intrinsic chemical stability and super sulfonic acid strength which is core to the PEMFC proton conductivity. This thesis presents a deeper analysis into these PFSA …
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Activating oxygen chemistry on metal and metal oxides: design principles of electrochemical catalysts
… many electrochemical energy devices, including polymer electrolyte membrane fuel cells (PEMFCs), water splitting electrolyzers, and rechargeable metal-air batteries, which hampers the development of new-energy applications such as electric vehicles. To increase the energy efficiency of ORR and …
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Understanding and Controlling Wettability of Carbon Powders for PEM Fuel Cell Applications
… to enhancing the performance and lifetime of polymer electrolyte membrane fuel cells (PEMFCs). As the CLs are composed of Pt nanoparticles supported on carbon powders, bound together with Nafion®, the main focus of this work was to understand and control the wettability of carbon materials for …
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Catalyst Layer Design in Polymer Membrane Fuel Cells
One of the biggest obstacles to commercializing polymer electrolyte membrane fuel cells is the use of platinum as a catalyst. One way to overcome this obstacle is to replace platinum with non-platinum group metal (non-PGM) catalysts, particularly for the oxygen reduction reaction (ORR) in proton …
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Impact of carbon support chemistry, morphology, and structure on platinum catalyst durability for PEMFC applications
<p>Polymer electrolyte membrane fuel cells are a promising alternative energy source, capable of being deployed as successful replacements in many stationary and mobile applications. These devices, however, lack durability, and this has become one of the limiting factors for commercialization. Many …
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Σύνθεση, φυσικοχημικός και ηλεκτροχημικός χαρακτηρισμός ηλεκτροκαταλυτών για κυψελίδες καυσίμου υψηλής θερμοκρασίας pem
… χρησιμοποιηθεί ως καύσιµο σε κυψελίδες καυσίµου (fuel cells), όπου παράγεται ενέργεια µέσω ηλεκτροχηµικής αντίδρασης, με φιλικό προς το περιβάλλον τρόπο. Μεταξύ άλλων, οι κυψελίδες καυσίμου πολυμερικής μεμβράνης (Polymer Electrolyte Membrane Fuel Cells, PEMFCs) έχουν προσελκύσει το έντονο …
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Supported Cobalt Oxide Catalysts for the Preferential Oxidation of Carbon Monoxide: An in situ Investigation
… for power generation using proton-exchange or polymer electrolyte membrane fuel cells (PEMFCs). The removal of CO (0.5 – 2%) is essential as it negatively affects the performance of the Pt-based anode catalyst of PEMFCs. Among the various CO removal processes reported, the preferential …
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