Some characteristics of Al_2O_3- and CaO-modified LaFeO_3-based cathode materials for solid oxide fuel cells

摘要

Al_2O_3- and CaO-modified LaFeO_3 were tested as possible solid oxide fuel cell (SOFC) cathode materials. Their electrical and structural characteristics were studied. In the La(Fe_(1-x)Al_x)O_3 system, specific resistivities increase with increasing concentration of Al_2O_3. The sintered materials are porous and the average grain diameters decrease with increasing Al_2O_3 content. In the La_(1-x)Ca_xFeO_3 system, a new single phase, iso-structural with LaFeO_3, was observed for x = 0.5. The room temperature resistivities of La_(1-x)Ca_xFeO_y decrease with increasing values of x, up to x = 0.5. The resistivity of La_(0.5)Ca_(0.5)FeO_y is more than four orders of magnitude lower than the resistivity of LaFeO_3.