Optimization of SDC-(Li/Na)₂CO₃ composite electrolyte for low-temperature solid oxide fuel cell applications

In this paper, samarium doped ceria (SDC)-(Li/Na)₂CO₃ composite electrolytes with different carbonate content were prepared by two processes, i.e. dry process and wet process, in which carbonate content was chosen to be 20%, 25% and 30%. The effects of preparation process and carbonate content on the phase structure, morphology were observed by XRD and SEM. The electrical conductivitiy of these composite electrolytes were measured by ac. impedance spectroscopy at 400-600°C in air. The single cells based on these composite electrolytes was fabricated by dry pressing and the performances of hydrogen/air fuel cells were evaluated.