Master of Science, University of Akron, 2005, Chemical Engineering

The development of electrochemical converters (i.e. fuel cells) has attracted research interest during the last decades due to an increasing concern on the depletion of available fossil fuel reserves and environmental issues such as global warming and emission of pollutant gases. Solid oxide fuel cells have received special attention because of their higher energy efficiency, rapid electrode kinetics without using expensive electrocatalysts such as Pt, relative resistance to impurities in the fuel and the possibility of processing CO, CH4 and other Carbon based fuels. Extensive research efforts have resulted in the development of solid oxide fuel cell materials such as Yttria stabilized Zirconia (YSZ) electrolytes, Lanthanum or Calcium doped Strontium Manganite (LSM) cathodes and Ni-YSZ cermet anodes. YSZ electrolytes require high operation temperatures (~ 1000 °C) in order to achieve sufficient ionic conductivity, placing large restrictions to candidate electrode, interconnect and housing materials. As a result, the cost of solid oxide fuel cell systems has become an important factor preventing their commercialization. Recent research efforts have shown that a variety of samarium doped oxides can be used as electrolyte and electrode materials in order to develop solid oxide fuel cells operating in intermediate temperatures. Samarium doped Ceria (SDC) has been shown to possess sufficient ionic conductivity at intermediate temperatures (600-800 °C). iv Similarly, Strontium doped Samarium Cobaltite (SSC) has been shown to act as an active electrode material. During this study we developed a synthesis procedure in order to fabricate a samarium doped ceria electrolyte and a samarium strontium cobaltite electrode material. Different fabrication conditions were tested in order to elucidate a procedure to manufacture an intermediate temperature fuel cell using an SDC electrolyte and two SSC electrodes. The impact of several fabrication variables on the resulting fuel cell (open full item for complete abstract)

Committee: Steven Chuang (Advisor) Subjects: Engineering, Chemical