High performance of La0.6Sr0.4Co0.2Fe0.8O3–Ce0.9Gd0.1O1.95 nanoparticulate cathode for intermediate temperature microtubular solid oxide fuel cells

The perovskite La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 –Ce 0.9 Gd 0.1 O 1.95 (LSCF–GDC) nanoparticulate cathode was applied for microtubular solid oxide fuel cells operated at intermediate temperatures. For the cell with the cathode sintered at 950 °C, maximum power densities of 0.26, 0.54 and 0.73 W cm −2 were obtained at 550, 600 and 650 °C, respectively. The ohmic resistance increased for the cathode sintered at 850 °C, and the polarization resistance increased for the cathode sintered at 1050 °C. The cathode polarization resistances of ionic conduction process in the LSCF bulk and adsorption/desorption process on the LSCF surface were estimated by the distribution of relaxation times analysis, which were only 0.066 and 0.065 Ω cm 2 at 600 °C for the cathode sintered at 950 °C. The grain size of the cathode was less than 100 nm, which resulted in high performance due to an overall decrease in cathode polarization resistance.