Multielectronic conduction in La1−xSrxGa1/2Mn1/2O3−δ as solid oxide fuel cell cathode

Four-probe dc conductivities, capacitances, and thermopower have been measured in the temperature range of 80–1123 K for La1−xSrxGa1/2Mn1/2O3−δ, which is a desirable cathode material for lanthanum–gallate electrolytes of solid oxide fuel cells. The dc conductivities in the specimens (0.1⩽x⩽0.3) are insensitive to x but the thermopower is very sensitive to x, although the x=0 specimen exhibits a somewhat different conduction behavior. At T 500 K, the band cond...