Low temperature solid oxide fuel cells with hierarchically porous cathode nano-network

Cost and reliability of solid oxide fuel cell (SOFC) system resulting from high operating temperature severely hinders its wide-spread commercialization. In this study, high performance low temperature SOFCs with hierarchically porous nano cathode network (Sm0.5Sr0.5CoO3-Gd0.1Ce0.9O2-delta, SSC-GDC) have been fabricated by vacuum-free infiltration and subsequent freeze-drying combustion. The straight open GDC cathode skeleton and NiO-GDC anode substrate prepared by freeze-drying tape-casting facilitate mass transport while the nano cathode catalyst promotes the electrochemical reactions. The cell with straight open electrodes and hierarchically porous cathode network demonstrates a maximum power density of 0.65 W cm(-2) at 500 degrees C and impressive stability for more than 500 h at 400 degrees C using H-2 as fuel and ambient air as oxidant. The simple and cost-effective fabrication process is expected to significantly impact the SOFC operability and accelerate its commercialization. (C) 2014 Elsevier Ltd. All rights reserved.