Cobalt-free cathode material SrFe0.9Nb0.1O3− for intermediate-temperature solid oxide fuel cells

Abstract

A cobalt-free cubic perovskite oxide, SrFe0.9Nb0.1O3−δ (SFN) was investigated as a cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). XRD results showed that SFN cathode was chemically compatible with the electrolyte Sm0.2Ce0.8O1.9 (SDC) for temperatures up to 1050 °C. The electrical conductivity of SFN sample reached 34–70 S cm−1 in the commonly operated temperatures of IT-SOFCs (600–800 °C). The area specific resistance was 0.138 Ω cm2 for SFN cathode on SDC electrolyte at 750 °C. A maximum power density of 407 mW cm−2 was obtained at 800 °C for single-cell with 300 μm thick SDC electrolyte and SFN cathode.