Abstract

Single phase La_1 − xSr_xMn_0.5Cr_0.5O_3 ± δ (LSMC, x_Sr = 0 and 0.2) and composite LSMC:Gd-doped ceria (GDC) mixed ionic and electronic conducting anodes were studied in half-cell and full-cell electrochemical configurations using humidified fuel environments at 700 to 800 °C. We demonstrate here that the removal of Sr from La_1 − xSr_xMn_0.5Cr_0.5O_3 ± δ improves both the thermo-chemical stability and the electronic conductivity of these materials in a humidified H₂ environment, while also enhancing their H₂ oxidation activity, when operating at 700 and 800 °C. It is also shown that the addition of 50:50 wt.% GDC:LaMn_0.5Cr_0.5O_3 ± δ results in the retention of all of these benefits, as compared to a mixture of GDC with the Sr-containing La_0.8Sr_0.2Mn_0.5Cr_0.5O_3 ± δ (x_Sr = 0.2) oxide.