Fabrication and electrochemical characterizations of Nd2NiO4+δ-Ce0.8Gd0.2O2−δ composite cathodes for anode-supported intermediate temperature solid oxide fuel cells

Nd2NiO4+δ (NNO)-Ce0.8Gd0.2O2−δ (CGO) composites were investigated as cathodes for intermediate temperature solid oxide fuel cells (IT-SOFCs). Planar NiO-YSZ anode-supported cells in size of 50 mm × 50 mm were fabricated with YSZ as the electrolyte. The effects of sintering temperature and the relative proportions of NNO and CGO on the cell performance were investigated in combination with chemical reactivity tests of NNO-YSZ and NNO-CGO. NNO-CGO composite cathodes were successfully sintered on YSZ electrolyte at 1000 °C. By using La0.6Sr0.4CoO3−δ (LSC) as current collector, the cell with 70NNO-30CGO composite cathode sintered at 1000 °C exhibited the highest power density of 620 mW cm−2 (at 0.7 V) and the lowest polarization resistance of 0.302 Ω cm2 at 800 °C. Short-term durability studies revealed that the degradation of cell performance was attributed to the crack formation on the LSC current collector layer and the delamination between NNO-CGO cathode layer and LSC current collector layer.