Porous Ag–Ce0.8Sm0.2O1.9 cermets as anode materials for intermediate temperature solid oxide fuel cells using CO fuel

To study anode materials for intermediate temperature solid oxide fuel cells with Ce0.8Sm0.2O1.9 (CSO) electrolyte using CO fuel, highly porous Ag–CSO cermets are prepared with MgO pore former and characterized. A single cell with 45Ag–CSO anode (Ag content: 45 wt%) is fabricated, tested, and compared with the similar cell with Cu–CeO2–CSO anode. The 45Ag–CSO cermet shows high porosity (47%), high electrical conductivity (1254 S cm−1 at 923 K in CO), high activity ( 0.58m〖mol〗_CO 〖min〗^(-1) g_Cat^(-1)) and stability for CO oxidation at 923 K, and no carbon deposition. The single cell with 45Ag–CSO anode shows high open circuit voltage (1.13 V at 923 K and 1.11 V at 973 K with pure CO as the fuel and air as the oxidant), high maximum power density (MPD, 178.4 mW cm−2 at 923 K and 438.8 mW cm−2 at 973 K), and high stability (no apparent change in MPD over 100 h test at 973 K). This cell is much better in performance than the cell with Cu–CeO2–CSO anode. Given that the CSO electrolyte is 0.385 mm thick, the performance is very encouraging. All the results suggest that the porous 45Ag–CSO cermet is an excellent anode material for ITSOFC with CSO electrolyte using CO fuel.