Cathodic properties of La0.9Sr0.1MnO3 electrode for fuel cells based on LaGaO3 solid electrolyte

Since LaMnO3 cathode shows good electrode properties for fuel cells employing YSZ (Yttria Stabilized Zirconia) electrolyte, it is interesting to see if LaMnO3 can also be used as an electrode material for LaGaO3- based fuel cells. In this study, the cathodic properties of La0.9Sr0.1MnO3 (LSM) and LSM mixed with La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM) were studied. When LSM was mixed with LSGM for electrode, the resulting mixture cathode showed the lower overpotential than that for LSM. It also showed the smaller particle size than LSM in addition to the expected mixed conductivity. The cathodic overpotential of LSM was much higher on LSGM electrolyte than that on YSZ electrolyte due possibly to the insulating phase produced by the reaction between LSM and LSGM. With varying cell preparation condition, it was shown that the thickness of reaction layer can be controlled, and the electrode overpotential can be reduced.