Characteristics of Pt Electrode Activated by Tb1 − xCexO2 − α Films in Contact with ZrO2 + 10 mol % Y2O3 Electrolyte

A. I. Kovrova A. I. Kovrova , V. P. Gorelov V. P. Gorelov
Российский электрохимический журнал
Abstract / Full Text

Porous platinum electrodes on ZrO2 + 10 mol % Y2O3 solid electrolyte (YSZ) are activated by Tb1 − xCexO2 − α (x = 0; 0.15; 0.33; 0.5; 1.0) mixed oxides by impregnation, and their polarization characteristics are studied. The activation is carried out under the conditions that an oxide activator nanofilm forms on the electrolyte surface as a result of heat treatment of the electrode. The activation is performed by impregnating the electrodes with low-concentrated alcohol solution of terbium and cerium nitrates (1.5% as recalculated to the oxides) and subsequent slow heating (≤50°C/h) to 850°C. An average thickness of the film on the electrolyte after a single activation (≈0.1 mg oxides/cm2) is estimated at 10–20 nm. The electrodes of Pt|YSZ|Pt cell activated by Tb1 − xCexO2 − α films are studied by the impedance method in the oxidative and reductive atmospheres in the range of 700 to 500°C. The polarization conductivities of the activated electrodes increase by 2–3 orders of magnitude. The studied electrodes are discussed within the model of compact oxide electrodes, where platinum plays the role of collector. The advantage of these electrodes is that they can work both in the oxidative and reductive conditions. According to the aggregate of the properties, Tb1 − xCexO2 − α compounds at x = 0.3–0.5 are recommended for activation.

Author information
  • Institute of High-Temperature Electrochemistry, Ural Branch, Russian Academy of Sciences, Yekaterinburg, 620137, Russia

    A. I. Kovrova & V. P. Gorelov

  1. Chen, M., Liu, T., and Lin, Z., Theory for the conductivity of nanoparticle-infiltrated SOFC electrode, ECS Transactions, 2013, vol. 57, p. 2763.
  2. Bertei, A., Pharoah, J.G., Gawel, D.A.W., and Nicolella, C., A particle-based model for effective properties in infiltrated solid oxide fuel cell electrodes, J. Electrochem. Soc., 2014, vol. 161, p. 1243.
  3. Ramos, T., Veltze, S., Sudireddy, B.R., Jordensen, P.S., Theil Kuhn, L., and Holtappels, P., Effect of Ru/CGO versus Ni/CGO co-infiltration on the performance and stability of STN-based SOFCs, Fuel Cells, 2014, vol. 14, p. 1062.
  4. Tang, D., Han, M.-F., and Zheng, Z.-W., Fabrication and performance of La0.6Sr0.4Co0.2Fe0.8O3−δ infiltrated-yttria-stabilized zirconia cathode on anode-supported solid oxide fuel cell, J. Fuel Cell Sci. Technol., 2015, vol. 12, p. 011001.
  5. Kishimoto, M., Lomberg, M., Ruiz-Trejo, E., and Brandon, N.P., Enhanced triple-phase boundary density in infiltrated electrodes for solid oxide fuel cells demonstrated by high-resolution tomography, J. Power Sources, 2014, vol. 266, p. 291.
  6. Yaroslavtsev, I.Yu., Bronin, D.I., Vdovin, G.K., and Isupova, L.A., Oxide cathodes for electrochemical devices made with the use of a nanostructured composition material, Russ. J. Electrochem., 2012, vol. 48, p. 981.
  7. Vshivkova, A.I. and Gorelov, V.P., The method of manufacture of electrodes of electrochemical devices with solid electrolyte. Russian Patent 2543071, 2015.
  8. Vshivkova, A.I. and Gorelov, V.P., Activation of oxygen reaction by praseodymium oxide film on platinum electrode in contact with YSZ electrolyte, Russ. J. Electrochem., 2016, vol. 52, p. 488.
  9. Kovrova, A.I. and Gorelov, V.P., Films of certain oxides of rare-earth elements as the activators of platinum electrode on ZrO2 + 10 mol % Y2O3 electrolyte, Russ. J. Electrochem., 2017, vol. 5, p. 522.
  10. Rutman, D.S., Toropov, Yu.S., Pliner, S.Yu., Neuimin, A.D., and Polezhaev, Yu.M., Vysokoupornye materialy iz dioksida tsirkoniya (High-Refractory Materials of Zirconium Dioxide), Moscow: Metallurgiya, 1985.
  11. Vshivkova, A.I., Gorelov, V.P., Kuz’min, A.V., Plaksin, S.V., Pankratov, A.A., and Yaroslavtseva, T.V., Preparation and physicochemical properties of praseodymium oxide films and ceramics, Inorg. Mater., 2015, vol. 51, p. 1168.
  12. Wang, X, Hanson, J.C., Liu, G., and Rodrigueza, J.A., The behavior of mixed-metal oxides: Physical and chemical properties of bulk Ce1 − xTbxO2 and nanoparticles of Ce1 − xTbxOy, J. Chem. Phys., 2004, vol. 121, p. 5334.
  13. Coduri, M., Scavini, M., Brunelli, M., Pedrazzin, E., and Masala, P., Structural characterization of Tb- and Pr-doped ceria, Solid State Ionics, 2014, vol. 268, p. 150.
  14. Kim, J.J., Bishop, S.R., Chen, D., and Tuller, H.L., Defect chemistry of Pr doped ceria thin films investigated by in situ optical and impedance measurement, Chem. Mater., 2017, vol. 29, p. 1999.