Effects of Anode Microstructure on the Performances of Cathode-Supported Micro-SOFCs

The effect of anode microstructure on the electrochemical performance of cathode-supported micro solid oxide fuel cells (SOFCs) was evaluated using current-voltage and ac impedance measurements. Small-scale cells were fabricated by the extrusion of a microtubular (La(0.8)Sr(0.2))(0.97)MnO(3) support and subsequent surface coating with a Ce(0.9)Gd(0.1)O(1.95)/Sc(2)O(3)-doped ZrO(2) bilayer electrolyte and NiO-Ce(0.9)Gd(0.1)O(1.95) anode layers. Impedance analysis and scanning electron microscopy observations indicate that an anode layer with coarse NiO particles has a higher porosity and electrode activity than that with fine NiO particles. The SOFC with coarse NiO particles generated more than twice the power density of that with fine NiO particles.