SrCo0.9Sb0.1O3-δ cubic perovskite as a novel cathode for intermediate-to-low temperature SOFCs

Abstract

The SrCo0.9Sb0.1O3-δ (SCS) composite oxide with cubic perovskite structure was synthesized by a modified Pechini method, and examined as a novel cathode for intermediate-to-low temperature solid oxide fuel cells (ILT-SOFCs). At 700°C and under open-circuit condition, a symmetrical SCS cathode on Sm0.2Ce0.8O1.9 (SDC) electrolyte showed a low polarization resistance (Rp) of 0.09 Ωcm2 in air. A porous layer of SCS was deposited on an anode-supported fuel cell, consisting of a ∼30 μm thick dense electrolyte of SDC prepared by a cost-effective dip coating process, and an NiO-SDC cermet as an anode (Ni-SDC/SDC/SCS). The single cells obtained were tested with humidified (∼3% H2O) hydrogen as fuel and static air as oxidant. A high open-circuit voltage of 0.86 V, a maximum power density of 354 mW/cm2, and a low polarization resistance of the electrodes of 0.13 Ωcm2 was achieved at 650°C. © 2009 Elsevier Ltd. All rights reserved.