Electrochemical effects of cobalt doping on (La,Sr)(Ga,Mg)O3−δ electrolyte prepared by aerosol deposition

(La,Sr)(Ga,Mg)O3−δ and (La,Sr)(Ga,Mg,Co)O3−δ electrolytes were aerosol deposited on conventionally sintered NiO-GDC anode substrates at room temperature to minimize reactions between them. Composite cathodes comprising (La,Sr)(Co,Fe)O3−δ and polyvinylidene fluoride were similarly deposited at room temperature. Both electrolytes and cathode maintained good adhesion. Cobalt in the electrolyte reduced open cell voltage (∼0.8 V vs. ∼1.1 V) probably due to the decrease of ionic transfer number, and increased maximum power density (∼0.8 W/cm2 vs. ∼0.5 W/cm2 at 650 °C) by increasing ionic conductivity.