Solid State Ionics, Vol.260, 43-48, 2014
SrFe0.8Mo0.2O3-delta: Cathode material for intermediate temperature solid oxide fuel cells
As a mixed oxygen ionic and electronic conductor, SrFe0.8Mo0.2O3-delta is confirmed to be a good cathode material for intermediate-temperature solid-state fuel cells (IT-SOFCs). The sample of SrFe0.8Mo0.2O3-delta is synthesized by a solid-state reaction method. Pure cubic SrFe0.8Mo0.2O3-delta perovskite, with space group of Pm-3 m (no. 221) and lattice parameter a = 3.9120(1) angstrom, is determined via Powder X-ray Rietveld refinements. X-ray photoelectron spectroscopy testifies the existence of mixed oxidation states Fe2+/3+/4+ and Mo5+/6+ in the crystal. Thermogravimetry analysis consistently shows that the SrFe0.8Mo0.2O3-delta begins to the loss of lattice oxygen at about 450 degrees C, which overlaps to the inflection temperature of the electrical conductivity profile. The maximum electrical conductivity obtained is about 50.20 S cm(-1) at 450 degrees C, and the impedance 0.11 Omega cm(2) at 850 degrees C. The performance demonstrates that SrFe0.8Mo0.2O3-delta is a potential candidate as a cathode material for IT-SOFCs. (C) 2014 Elsevier B.V. All rights reserved.