Ni–Fe bimetallic anode as an active anode for intermediate temperature SOFC using LaGaO 3 based electrolyte film

Abstract

Effects of additives to Ni anode were studied and it was found that the anodic overpotential can be suppressed by addition of Fe. La 0.9Sr 0.1Ga 0.8Mg 0.2O 3 (LSGM) film was deposited on the dense anode substrate consisting of NiO(Fe 3O 4)–Sm doped CeO 2. After in-situ reduction of NiO and Fe 3O 4 in the dense substrate, the substrate turned to be porous, however, change in size was not large by mixing with SDC. As a result, LSGM dense film with few micrometer thickness was successfully obtained on the porous Ni based anode substrate. By optimizing the thickness of the LSGM film and application of SDC interlayer, the high power density of SOFC single cell using LSGM/SDC bi-layer film as electrolyte at decreased temperature was fabricated and the electrical power generating property was measured as a function of temperature. The high maximum power density could be achieved to a value of 2 W/cm 2 at 873 K. Even at 673 K, the maximum power density of ca. 80 mW/cm 2 is exhibited and this high power density was a result of the low electrolyte resistance and the small anodic overpotential of Ni–Fe bimetallic anode.