A perovskite oxide with high conductivities in both air and reducing atmosphere for use as electrode for solid oxide fuel cells

Electrode materials which exhibit high conductivities in both oxidising and reducing atmospheres are in high demand for solid oxide fuel cells (SOFCs) and solid oxide electrolytic cells (SOECs). In this paper, we investigated Cu-doped SrFe(0.9)Nb(0.1)O(3−δ) finding that the primitive perovskite oxide SrFe(0.8)Cu(0.1)Nb(0.1)O(3−δ) (SFCN) exhibits a conductivity of 63 Scm(−1)and 60 Scm(−1) at 415 °C in air and 5%H(2)/Ar respectively. It is believed that the high conductivity in 5%H(2)/Ar is related to the exsolved Fe (or FeCu alloy) on exposure to a reducing atmosphere. To the best of our knowledge, the conductivity of SrFe(0.8)Cu(0.1)Nb(0.1)O(3−δ) in a reducing atmosphere is the highest of all reported oxides which also exhibit a high conductivity in air. Fuel cell performance using SrFe(0.8)Cu(0.1)Nb(0.1)O(3−δ) as the anode, (Y(2)O(3))(0.08)(ZrO(2))(0.92) as the electrolyte and La(0.8)Sr(0.2)FeO(3−δ) as the cathode achieved a power density of 423 mWcm(−2) at 700 °C indicating that SFCN is a promising anode for SOFCs.