Development and Characterization of Cathode-Supported SOFCs by Single-Step Cofiring Fabrication for Intermediate Temperature Operation

Abstract

In this study, a single-step cofiring through the extrusion molding and wet-ceramic coating technique was developed to fabricate a cathode-supported microtubular cell. The cell is consisting of a Ce0.9Gd0.1O1.95 (GDC) electrolyte with a NiO–GDC anode on a porous La0.6Sr0.4Co0.2Fe0.8O3−δ∕GDC tube (460μm wall thickness and 2.26mm diameter). Densification of the ceria membrane (thickness <20μm) was successful by cosintering the laminated thin electrolyte and the anode with the cathode at 1200°C. Compared with that fabricated by the conventional two-step cofiring process, the cell showed an improved performance due to the increased anode sintering temperature, which leads to an improved anode∕electrolyte interfacial property. The cell having 2cm tube length fed with humidified 30vol%H2–Ar (3% H2O) produced the maximum power densities of 0.09Wcm−2, 0.08Wcm−2, and 0.05Wcm−2, at 600°C, 550°C, and 500°C, respectively.