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Stanko Hočevar - One of the best experts on this subject based on the ideXlab platform.

  • Computational fluid dynamics study of phosphotungstic acid electrolyte-Based Fuel Cell (PWAFC)
    Journal of Power Sources, 2001
    Co-Authors: Igor Lavrič, Pietro Staiti, Peter Novak, Stanko Hočevar
    Abstract:

    The computational fluid dynamics (CFD) study of the mass and heat transfer in the phosphotungstic acid electrolyte-Based Fuel Cell (PWAFC) was performed in order to elucidate the cause of irregular Fuel Cell work failures at high current densities, which manifested through partial melting of the matrix and electrodes and crossover effect. It was established that the reason for these difficulties is not the damage (cracks) of the catalyst layer in the gas diffusion electrode, but the bad construction of the reactant gas and liquid electrolyte distributors on cathode and anode side of the PWAFC and the lack of cooling system. The CFD study pointed to several practical conclusions how to improve the PWAFC construction.

  • Analysis of the chemical cross-over in a phosphotungstic acid electrolyte Based Fuel Cell
    Electrochimica Acta, 1997
    Co-Authors: N. Giordano, Pietro Staiti, Antonino S. Aricò, Enza Passalacqua, L. Abate, Stanko Hočevar
    Abstract:

    The mechanism of the chemical cross-over in a low temperature Fuel Cell Based on a phosphotungstic acid electrolyte (PWA) was investigated. It was observed that a parasitic chemical process involving redox reactions of the reagent gases with the electrolyte caused a coulombic loss and a detrimental effect on the polarization curves. The total consumption of reagent gases was determined and compared to the Faradaic consumption. Polarization curves carried out under constant gas utilization (0.66) showed that the decrease of electrochemical activity with respect to the experiments conducted with a stoichiometric-excess of reagent gas feed was quite limited. It was observed that the electrochemical losses were more significant when the Cell was operated at low current density or under open circuit conditions, whereas, the electrochemical activity of the PWA Fuel Cell appeared to be little affected by the chemical cross-over at high current densities.

Pietro Staiti - One of the best experts on this subject based on the ideXlab platform.

  • Computational fluid dynamics study of phosphotungstic acid electrolyte-Based Fuel Cell (PWAFC)
    Journal of Power Sources, 2001
    Co-Authors: Igor Lavrič, Pietro Staiti, Peter Novak, Stanko Hočevar
    Abstract:

    The computational fluid dynamics (CFD) study of the mass and heat transfer in the phosphotungstic acid electrolyte-Based Fuel Cell (PWAFC) was performed in order to elucidate the cause of irregular Fuel Cell work failures at high current densities, which manifested through partial melting of the matrix and electrodes and crossover effect. It was established that the reason for these difficulties is not the damage (cracks) of the catalyst layer in the gas diffusion electrode, but the bad construction of the reactant gas and liquid electrolyte distributors on cathode and anode side of the PWAFC and the lack of cooling system. The CFD study pointed to several practical conclusions how to improve the PWAFC construction.

  • Analysis of the chemical cross-over in a phosphotungstic acid electrolyte Based Fuel Cell
    Electrochimica Acta, 1997
    Co-Authors: N. Giordano, Pietro Staiti, Antonino S. Aricò, Enza Passalacqua, L. Abate, Stanko Hočevar
    Abstract:

    The mechanism of the chemical cross-over in a low temperature Fuel Cell Based on a phosphotungstic acid electrolyte (PWA) was investigated. It was observed that a parasitic chemical process involving redox reactions of the reagent gases with the electrolyte caused a coulombic loss and a detrimental effect on the polarization curves. The total consumption of reagent gases was determined and compared to the Faradaic consumption. Polarization curves carried out under constant gas utilization (0.66) showed that the decrease of electrochemical activity with respect to the experiments conducted with a stoichiometric-excess of reagent gas feed was quite limited. It was observed that the electrochemical losses were more significant when the Cell was operated at low current density or under open circuit conditions, whereas, the electrochemical activity of the PWA Fuel Cell appeared to be little affected by the chemical cross-over at high current densities.

Raymond J. Gorte - One of the best experts on this subject based on the ideXlab platform.

  • Direct oxidation of hydrocarbons in a solid-oxide Fuel Cell
    Nature, 2000
    Co-Authors: Seungdoo Park, John M Vohs, Raymond J. Gorte
    Abstract:

    The direct electrochemical oxidation of dry hydrocarbon Fuels to generate electrical power has the potential to accelerate substantially the use of Fuel Cells in transportation and distributed-power applications. Most Fuel-Cell research has involved the use of hydrogen as the Fuel, although the practical generation and storage of hydrogen remains an important technological hurdle. Methane has been successfully oxidized electrochemically, but the susceptibility to carbon formation from other hydrocarbons that may be present or poor power densities have prevented the application of this simple Fuel in practical applications. Here we report the direct, electrochemical oxidation of various hydrocarbons (methane, ethane, 1-butene, n-butane and toluene) using a solid-oxide Fuel Cell at 973 and 1,073 K with a composite anode of copper and ceria (or samaria-doped ceria). We demonstrate that the final products of the oxidation are CO2 and water, and that reasonable power densities can be achieved. The observation that a solid-oxide Fuel Cell can be operated on dry hydrocarbons, including liquid Fuels, without reforming, suggests that this type of Fuel Cell could provide an alternative to hydrogen-Based Fuel-Cell technologies.

Helinando P. De Oliveira - One of the best experts on this subject based on the ideXlab platform.

  • Improvement of Baker's yeast-Based Fuel Cell power output by electrodes and proton exchange membrane modification.
    Materials science & engineering. C Materials for biological applications, 2019
    Co-Authors: Ariadne Helena Pequeno De Oliveira, Jose J. Alcaraz-espinoza, Mateus Matiuzzi Da Costa, Marcio Luis Ferreira Nascimento, Timothy M. Swager, Helinando P. De Oliveira
    Abstract:

    Abstract The production of more efficient yeast-Based Fuel Cells (YFCs) depends on a combination of effective proton exchange membranes, electron mediators and current collectors. The adhesion of organisms on electrode surface plays a key role in the electron transfer process optimizing the generated power density. In this work, it is reported the preparation of a new YFC prototype using membranes of polyvinyl alcohol/ phosphoric acid and anodes of carbon nanotubes/polyurethane. The high surface area for yeast adhesion and the strong interaction established between Cells/carbon nanotubes favor the energy generation in Fuel Cell. To evaluate the influence of external mediators and the consumption of feed solution (glucose) on performance of YFC, the kinetics of current generation of resulting Fuel Cells was analyzed. Results reveal that increases in the impedance of electrodes on generated power can be minimized by periodical infusion of feed Fuel, preserving 70% of maximum power, representing an important condition for prolonged activity of Fuel Cell.

Mani Narayanasamy - One of the best experts on this subject based on the ideXlab platform.

  • Ultra-low loading of platinum in proton exchange membrane-Based Fuel Cells: a brief review
    Materials for Renewable and Sustainable Energy, 2019
    Co-Authors: Aristatil Ganesan, Mani Narayanasamy
    Abstract:

    This review report summarizes different synthesis methods of PEM-Based Fuel Cell catalysts with a focus on ultra-low loading of Pt catalysts. It also demonstrates Fuel Cell performances with ultra-low loading of Pt catalysts which have been reported so far, and suggests a combination method of synthesis for an efficient Fuel Cell performance at a low loading of Pt catalyst. Here, maximum mass-specific power density (MSPD) values are calculated from various reported performance values and are discussed, and compared with the Department of Energy (DOE) 2020 target values.