Chemically stable and coke resistant Sm1-xCexFeO3-δ perovskites for low temperature solid oxide fuel cell anode applications

Sm1-xCexFeO3-delta (x = 0-0.05) perovskite materials were investigated as anodes for low-temperature solid oxide fuel cells (LT-SOFCs) using dry hydrogen and dry methane fuels. Ce doping changes the electrical behaviour of SmFeO3 from p-type to n-type and improves the reduction stability under the strong reducing atmosphere required at the anode. The resulting Ce doped materials presented good and stable performances as anodes under hydrogen and methane fuels. The Sm0.95Ce0.05FeO3-delta anode showed the lowest charge transfer resistances in the series at 700 degrees C, 0.05 Omega cm(2) and 1.4 Omega cm(2) under dry hydrogen and methane, respectively. At 450 degrees C, the Sm0.95Ce0.01FeO3-delta anode demonstrated performance with an open circuit potential (OCP) of 0.690 V and lowest R-ct of 1.5 k Omega cm(2) under dry methane fuel. More importantly no visible coking was found on the surface of these anodes after the performance under dry methane for similar to 23 h at all temperatures. (C) 2011 Elsevier B.V. All rights reserved.