Improvement of a GDC-based composite cathode for intermediate-temperature solid oxide fuel cells

Abstract

La0.84Sr0.16MnO3−δ - Ce0.8Gd0.2O2-δ (LSM-GDC) composite cathodes were fabricated by impregnating the LSM matrix with both LSM′ (La0.84Sr0.16MnO3−δ) and GDC (or only GDC), and the ion-impregnated LSM-GDC composite cathodes showed excellent performance. At 750 °C, the value of the cathode polarization resistance (Rp) was only 0.058 Ω cm2 for an ion-impregnated LSM-GDC composite cathode which was impregnated with both LSM′ and GDC. For the performance of the single cell with the same cathode, the maximum power density was 1.1 W cm−2 at 750 °C. The long-term test of the cell was carried out at 700 °C with a constant load of 0.3 A cm−2 and the output voltage was stable on the whole. The results demonstrated that LSM-GDC fabricated by impregnating the LSM matrix with both LSM′ and GDC was a promising composite cathode material for the intermediate-temperature solid oxide fuel cells.