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Electrochemical dispersion technique for preparation of hybrid MO x –C supports and Pt/MO x –C electrocatalysts for low-temperature fuel cells

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Abstract

Hybrid MOx–C (M = Sn, Ni) supports and Pt/MO x –C catalysts for direct alcohol fuel cells were prepared via the electrochemical oxidation and dispersion of a metal under the influence of a pulsed alternating current. We estimated conductivity and specific surface area of as-prepared SnO2, NiO and hybrid supports, as well as estimated their morphology and the morphology of Pt-based catalysts using X-ray diffraction, transmission and scanning electron microscopy analyses. Pt/MO x –C (M = Sn, Ni) catalytic systems with oxide contents of 30 and 60 % in hybrid supports and a Pt content of 25 % were used for the electrochemical oxidation of CO, methanol and ethanol in acidic and alkaline solutions. The presence of oxides in the hybrid supports for catalysts reduces the onset potential for the electrooxidation of CO and alcohols in an acidic solution. At Pt/SnO2–C, the onset potential of ethanol electrooxidation in an acidic solution decreases by 170 mV and increases the rate of the oxidation process by more than sevenfold at the low Tafel potential region. In alkaline solutions, the presence of metal oxides in the catalysts is not so effective, which is probably due to the high coverage of the platinum surface with oxygen-containing species. The Pt catalyst on the SnO2–C hybrid support exhibited superior electrochemical stability in an acidic solution and Pt/NiO–C—in an alkaline solution. The difference in the optimum oxide content (30 % for SnO2, 60 % for NiO) of the catalysts can be attributed to different morphologies of the oxides.

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Acknowledgments

The financial support by the Russian Science Foundation (Grant No. 14-23-00078) is gratefully acknowledged.

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Authors and Affiliations

  1. Platov South-Russian State Polytechnic University (NPI), Prosveschenia Str. 132, Novocherkassk, Russian Federation, 346428

    A. B. Kuriganova, D. V. Leontyeva & N. V. Smirnova

  2. Don State Technical University, Gagarin Square 1, Rostov-on-Don, Russian Federation, 344000

    D. V. Leontyeva

  3. Electrochemistry and Electroplating Group, Technische Universitaet Ilmenau, Gustav-Kirchhoff-Str. 6, 98693, Ilmenau, Germany

    S. Ivanov & A. Bund

  4. National University of Science and Technology “MISiS”, Leninskiy Prospect 4, Moscow, Russian Federation, 119049

    N. V. Smirnova

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  1. A. B. Kuriganova
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  3. S. Ivanov
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Kuriganova, A.B., Leontyeva, D.V., Ivanov, S. et al. Electrochemical dispersion technique for preparation of hybrid MO x –C supports and Pt/MO x –C electrocatalysts for low-temperature fuel cells. J Appl Electrochem 46, 1245–1260 (2016). https://doi.org/10.1007/s10800-016-1006-5

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