A-Site Deficient Lanthanum Strontium Chromite Oxide with In-Situ Growth of Ni-Co Nano-Alloys: A Potential Electrode Catalyst for Solid Oxide Fuel Cell

• Author / Creator

  Cui,Lin

• Solid oxide fuel cell (SOFC) is an advanced power generation device that has desirable fuel flexibility and higher efficiency compared to conventional electricity generators. Since SOFC requires different fuel gases for reactions, a catalytically active fuel electrode with excellent stability as well as good carbon deposition resistance is the real challenge for the cell. In this research, the in-situ exsolved bimetallic doped A-site deficient perovskite oxide: A-site deficient nickel (Ni) and cobalt (Co) bimetallic doped lanthanum strontium chromite oxide (LSC) has been fabricated as a potential fuel electrode for SOFC. The in-situ exsolution process of Ni-Co alloy has been elaborately studied from various aspects. The electrochemical performances of Ni-Co doped LSC are thoroughly compared with Ni doped LSC in hydrogen gas, syngas as the anode and in CO2 gas as the cathode. The fuel cell with a bimetallic doped LSC anode has shown maximum power densities of 329 mW/cm2 in hydrogen and 258 mW/cm2 in syngas compared with only 237mW/cm2 in hydrogen and 170 mW/cm2 in syngas for the fuel cell with the single metallic doped anode at 850℃. The Ni-Co doped electrode also has shown higher optimum operating voltage and better stability than the Ni doped electrode in cathode function. Ni-Co doped cells have demonstrated no obvious degradation during long-term operation as well as good carbon deposition resistance under the tested atmosphere. It can be postulated that the existence of A-site deficiency helps the formation of oxygen vacancies as well as enhances the reducibility of B-site ions. Meanwhile, the synergistic effect between Co and Ni has changed the reduction behavior of Ni particles that increased its reducibility and promoted its electrochemical performances as well as the carbon deposition resistance.

• Subjects / Keywords

  • A-Site Deficient Perovskite Oxide
  • Solid oxide fuel cells
  • In-Situ Exsolution

• Graduation date

  Spring 2017

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3Q52FR41

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.