Abstract
A porous composite cathode containing (La0.8Sr0.2)0.98MnO3 (LSM) and yttria stabilized zirconia (YSZ) for use in a solid oxide fuel cell has been produced by air plasma spraying. Deposition was carried out using axial powder injection for increased deposition efficiency and composition control. A plasma composed of argon and nitrogen was used to decrease processing costs and avoid decomposition of the cathode material during deposition. Preliminary investigations focused on determining the range of plasma conditions under which each of the materials could be successfully deposited separately. A set of conditions was thereby determined that were suitable for the deposition of a composite cathode from pre-mixed LSM and YSZ powders. Graphite pore former was added to the powder mixture in order to achieve sufficient porosity in the final coating. A tape cast YSZ electrolyte was used as the substrate for the deposition of the cathode and also as the mechanical support layer in the finished cell. Following deposition of the cathode, an anode was produced by traditional wet ceramic processing techniques. Plasma sprayed cathode was characterized by SEM, EDX, and XRD, and the electrochemical performance of the full fuel cell was evaluated.
