Change search
Refine search result
1 - 7 of 7
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Eiler, Konrad
    et al.
    Universitat Autònoma de Barcelona, Spain.
    Mölmen, Live
    RISE Research Institutes of Sweden, Safety and Transport, Electrification and Reliability. Jönköping University, Sweden.
    Fast, Lars
    RISE Research Institutes of Sweden, Safety and Transport, Electrification and Reliability.
    Leisner, Peter
    Jönköping University, Sweden.
    Sort, Jordi
    Universitat Autònoma de Barcelona, Spain; ICREA, Spain.
    Pellicer, Eva
    Universitat Autònoma de Barcelona, Spain.
    Oxygen reduction reaction and proton exchange membrane fuel cell performance of pulse electrodeposited Pt–Ni and Pt–Ni–Mo(O) nanoparticles2022In: Materials Today Energy, ISSN 2468-6069, Vol. 27, article id 101023Article in journal (Refereed)
    Abstract [en]

    Proton exchange membrane fuel cells (PEMFCs) are an important alternative to fossil fuels and a complement to batteries for the electrification of vehicles. However, their high cost obstructs commercialization, and the catalyst material, including its synthesis, constitutes one of the major cost components. In this work, Pt–Ni and Pt–Ni–Mo(O) nanoparticles (NPs) of varying composition have been synthesized in a single step by pulse electrodeposition onto a PEMFC's gas diffusion layer. The proposed synthesis route combines NP synthesis and their fixation onto the microporous carbon layer in a single step. Both Pt–Ni and Pt–Ni–Mo(O) catalysts exhibit extremely high mass activities at oxygen reduction reaction (ORR) with very low Pt loadings of around 4 μg/cm2 due to the favorable distribution of NPs in contact with the proton exchange membrane. Particle sizes of 40–50 nm and 40–80 nm were obtained for Pt–Ni and Pt–Ni–Mo(O) systems, respectively. The highest ORR mass activities were found for Pt67Ni33 and Pt66Ni32–MoOx NPs. The feasibility of a single-step electrodeposition of Pt–Ni–Mo(O) NPs was successfully demonstrated; however, the ternary NPs are of more amorphous nature in contrast to the crystalline, binary Pt–Ni particles, due to the oxidized state of Mo. Nevertheless, despite their heterogeneous nature, the ternary NPs show homogeneous behavior even on a microscopic scale. © 2022 The Author(s)

  • 2.
    Mölmen, Live
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Alexandersson, Anna
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics.
    Leisner, Peter
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Surface technology should improve PEM fuel cell performance2019In: Transactions of the Institute of Metal Finishing, ISSN 0020-2967, E-ISSN 1745-9192, Vol. 97, no 3, p. 112-114Article in journal (Refereed)
    Abstract [en]

    Leading industrial nations are investing in hydrogen technology as energy storage solution with fuel cells as the main converter to electric energy. Improvements in the performance of the key components: electrode catalyst, bipolar plates and polymer electrolyte membrane are needed to reduce costs for mass-market introduction. Consequently, surface technology has an essential role in meeting the goals. 

    Download full text (pdf)
    fulltext
  • 3.
    Mölmen, Live
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Braun, Maximilian
    FEM Forschungsinstitut Edelmetalle Metallchemie, Germany.
    Baumgärtner, Manfred
    FEM Forschungsinstitut Edelmetalle Metallchemie, Germany.
    Leisner, Peter
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Pt-P catalyst for fuel cells2019Conference paper (Other academic)
    Abstract [en]

    Fuel cell technology is becoming increasingly important in a society where the energy system is changing toward a high degree of electrification based on fossil-free primary sources of energy. Among commercial fuel cells, PEM (polymer electrolyte membrane) technology is dominating and the production is doubled each year. The reason for PEM technology being so prosperous is the ability of the industry to manufacture thin film materials (electrodes, membranes and protective films on bipolar plates), while also reaching high current densities. In order to improve the efficiency, catalysts are applied in the electrodes. These improvements have been achieved during the last decades thanks to significant materials development of membranes and electrodes, including micro- and nano-structuring and catalyst development by materials-doping. Thus, PEM technology has a strong potential to offer sustainable, cost effective and flexible solutions.

    However, PEM technology is sensitive to contamination of catalysts and membrane. Additionally, the demanding internal environment (chemistry, temperature, pressure, and dynamic operation make the conditions very harsh) poses complex challenges in terms of durability. Therefore, there are still challenges to overcome to make PEM technology more efficient and robust and thereby beneficial. The most important areas of materials development to reduce the cost of PEM fuel cells are

    • High-performance electrode catalysts enabling ultra-low precious metal loading,
    • Lower cost, lighter, corrosion-resistant bipolar plates,
    • Low cost, high-performance membranes.

    The purpose of the present work is synthesis of catalytic Pt and PtP nanoparticles onto the gas diffusion layer (GDL) of PEM fuel cells by electrodeposition, and in a next step to study aging during fuel cell testing.

    Pt particles with varying P concentration are electrodeposited onto the carbon paper GDL. The concentrations used were 0 at% P, 1 at% P and 10 at% P. The GDL is activated by plasma etching prior to electroplating. The electrolyte used, contained 8 gL-1 Pt as Pt(NO2)2(NH3)2, 70 gL-1  NaCH3COOH and 100 gL-1  Na2CO3. Phosphorous was added in the form of H3PO3. Pulsed electrodeposition was performed at a temperature of 30 °C with an on-time of 0.005 seconds and off-time of 0.195 s. The peak current was 5 A.

  • 4.
    Mölmen, Live
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Fast, Lars
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics.
    Andreatta, Francesco
    Università degli Studi di Udine, Italy.
    Leisner, Peter
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics.
    Pitting corrosion on coated stainless steel PEMFC flow plates2019Conference paper (Other academic)
    Abstract [en]

    The bipolar plate(BPP) constitutes up to 28% of the PEMFC stack cost[1]. Cheaper and more lightweight materials are needed, while there are strict requirements on both the mechanical and chemical stability within the acidic environment of the fuel cell. The targets set by the US DOE are a corrosion current <1 μA/cm2 and interfacial contact resistance <0.01 ohm cm2[2].

    Stainless steel is affordable and has the mechanical stability required for the BPPs. However, SS is subject to corrosion in the PEMFC environment. To be able to reach the DOE goals, either noble metal or conductive ceramic coatings must be utilised[3]. In this work, commercially available coatings on hydroformed SS 316L flow plates are studied. A single cell fuel cell tester is used to age the samples, and the in-situ degradation is measured by impedance measurements and polarisation curves. The electrochemical micro-cell technique is utilised to study the corrosion on both the pristine and aged flow plates by polarisation. SEM is used to analyse the surface. The aim is to better understand the pitting corrosion on PEMFC flow plates.

  • 5.
    Mölmen, Live
    et al.
    RISE Research Institutes of Sweden, Safety and Transport, Electrification and Reliability. Jönköping University, Sweden.
    Fast, Lars
    RISE Research Institutes of Sweden, Safety and Transport, Electrification and Reliability.
    Lundblad, Anders Olof
    RISE Research Institutes of Sweden, Safety and Transport, Electrification and Reliability.
    Eriksson, Peter
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Leisner, Peter
    Jönköping University, Sweden.
    Contact resistance measurement methods for PEM fuel cell bipolar plates and power terminals2023In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 555, article id 232341Article in journal (Refereed)
    Abstract [en]

    The electrical contact resistance is a key parameter for optimising both the bipolar plate of the polymer electrolyte membrane fuel cell (PEMFC) and the electrical contact of the power terminal of the stack. The contact resistance is affected by the conductivity, roughness, and hardness of the two contacting surfaces. Here, new, application-specific contact resistance measurement methods are proposed for both the stack power terminal, and the bipolar plate. The proposed methods are compared to methods from references as well as standards, and it is concluded that the uncertainty of the measurements can be reduced by changing the measurement setup, and that the influence of probe resistance on measurement results can be eliminated. Furthermore, the effect of different accelerated durability tests on the contact resistance of the power terminal is examined both on test coupons and on a prototype screw connection with an electroless NiP and an electroplated NiSn coatings. As expected, the NiSn coupons gives lower contact resistance after ageing as compared to the NiP. However, the increase in contact resistance seen on coupons after ageing is not observed on the prototype screw connection. © 2022 The Author(s)

  • 6.
    Mölmen, Live
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics.
    Lundblad, Anders Olof
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics.
    Fast, Lars
    Zanella, Caterina
    Jönköping University, Sweden.
    Leisner, Peter
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Investigation of feed water impurities on life-time of PEMWE2019Conference paper (Other academic)
    Abstract [en]

    With the introduction of fuel cell electric vehicles (FCEV), hydrogen gas produced without fossil fuels Is requiredto reduce the CO2 emissions. At the same time, the production of renewable energy is increasing. Waterelectrolysis to produce hydrogen with the use of electricity from renewable sources allows for storage of theenergy in the form of hydrogen. The gas can be utilized either back to the electric net or as fuel for FCEVs.However, the cost of water electrolysis systems needs to be reduced while the lifetime must be increased. Oneof the main limitations of the proton exchange membrane water electrolyser (PEMWE) system is the degradationof the membrane1. This limits the lifetime of the system and is expensive to replace. It has been shown thatimpurities from feed water and the degradation products from other component poison the membrane, loweringthe proton conductivity. Furthermore, metal ion impurities catalyse the formation of hydrogen peroxide at thecathode further contributing to irreversible membrane thinning2. In industrial systems, the water circulated tothe cells is purified to minimize the degradation. However, the purification limits the operating temperature ofthe systems and increases the total system cost2.The water quality used in most electrolysis cells today utilises ASTM type II deionized water. However, littleresearch is done on the limitations, and quantifying the reduction in efficiency dependent on the water quality.Dedigama et al.3 calculated the minimum flow needed, and further state that in industry, 5 times the necessaryflow of water is circulated to ensure proper wetting of the membrane. However, in research, an excess of wateris often used, up to 100 times higher flow than required, to exclude mass transport restrictions on thereactions3,4.Increasing temperature decreases the kinetic overpotential and increases the membrane conductivity4.However, also dissolution of the catalyst and degradation of the cell components increase with temperature.Furthermore, in industrial applications the maximum temperature of the water into the purification system is60°C5. Dependent on the aim of the research, experiments at temperatures as low as 25°C are performed to fitwith the industry, while others run at 80 or 90°C to probe the upper limits of current density and efficiency2.In this project we aim to analyse the effect of varying water purity on the membrane degradation in a single PEMelectrolysis cell test setup. Furthermore, the effect of changing temperature from 60 to 80°C on the impuritytolerance will be studied. The circulating feed water will be analysed with respect to conductivity, metal ion andfluorine concentration. A parallel “blank” system with only tubings, fittings etc will be assembled and comparedto the data measured from the electrolyser. Contaminating species will be added to the feed water to study theirimpact.

  • 7.
    Zendejas Medina, León
    et al.
    Uppsala University, Sweden.
    Mølmen, Live
    RISE Research Institutes of Sweden, Safety and Transport, Electrification and Reliability. Jönköping University, Sweden.
    Paschalidou, Eirini-Maria
    Uppsala University, Sweden.
    Donzel-Gargand, Olivier
    Uppsala University, Sweden.
    Leisner, Peter
    Jönköping University, Sweden.
    Jansson, Ulf
    Uppsala University, Sweden.
    Nyholm, Leif
    Uppsala University, Sweden.
    Extending the Passive Region of CrFeNi-Based High Entropy Alloys2023In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 33, no 51, article id 2307897Article in journal (Refereed)
    Abstract [en]

    This study provides principles for designing new corrosion resistant high entropy alloys. The theoretical framework is a percolation model developed by Newman and Sieradzki that predicts the ability of an alloy to passivate, i.e., to form a protective surface oxide, based on its composition. Here, their model is applied to more complex materials than previously, namely amorphous CrFeNiTa and CrFeNiW alloys. Furthermore, the model describes a more complex passivation process: reforming the oxide layer above the transpassive potential of Cr. The model is used to predict the lowest concentration of Ta or W required to extend the passive region, yielding 11–14 at% Ta and 14–17 at% W. For CrFeNiTa, experiments reveal a threshold value of 13–15 at% Ta, which agrees with the prediction. For CrFeNiW, the experimentally determined threshold value is 37–45 at% W, far above the predicted value. Further investigations explore why the percolation model fails to describe the CrFeNiW system; key factors are the higher nobility and the pH sensitivity of W. These results demonstrate some limitations of the percolation model and offer complementary passivation criteria, while providing a design route for combining the properties of the 3d transition metal and refractory metal groups. 

1 - 7 of 7
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf