Engineering the Solid Oxide Fuel Cell Through Infiltrating the Porous Electrodes

Abstract

Engineering the Solid Oxide Fuel Cell Through Infiltrating the Porous Electrodes Bryan Jackson Solid oxide fuel cells (SOFCs) are promising alternatives in energy conversion to produce energy electrochemically, with high energy conversion efficiency, instead of using the conventional combustion process. However, the current state of the art SOFCs need to be further improved in terms of performance and durability to become more economically competitive. In particular, improvements need to be made to increase the cell power density and lower the reaction resistance of porous electrode at operation temperature of 650-800 o C. Appropriate infiltration of nano materials into the porous composite electrode could lower the resistance and mitigate the electrode degradation. In this work numerous techniques are investigated for the infiltration of the conductors and elecrocatalyst into the porous anode and cathode, respectively. Nano-scaled oxide was introduced to porous Ni/YSZ anode with the aim of introducing the additional reaction pathway and increasing the coking resistance when fueled with hydrocarbons. Both the nano-scaled oxide and metallic particles were introduced to the porous LSM/YSZ cathode with the aim of lowering the resistance of oxygen reduction reaction. Impact of the infiltrate on the microstructure of the electrodes is evaluated through the combination of scanning electron microscopy, transmission electron microscopy, and energy dispersive x-ray spectroscopy. Electrochemical impedance spectroscopy (EIS) is used to study the effects of infiltrates on the change of resistance of SOFCs. Some appropriate infiltrate materials and suitable infiltration processes are thus determined for porous electrodes of SOFCs.