High Performance SrFe0.2Co0.4Mo0.4O3−δ Ceramic Anode Supported Low-Temperature SOFCs

Abstract

The development of alternative ceramic anodes for low-temperature solid oxide fuel cells (LT-SOFCs) is essential to overcome the inherent challenges such as redox instability and coking associated with Ni-based cermet anodes. Moreover, due to the large electrolyte ohmic loss at low temperature, it is critical to developing an electrode supported cell that allows electrolyte thickness reduction. Here we successfully demonstrated a high performance SrFe0.2Co0.4Mo0.4O3−δ (SFCM) ceramic anode supported LT-SOFC with a peak power density of 730 mW cm−2 and 300 mW cm−2 at ambitious low temperatures of 550 °C and 450 °C, respectively, in humidified H2. The new anode material SFCM exhibits exceptional conductivity of over 30 S cm−1 at 450 °C in humidified H2, providing essential current collection capability as an anode backbone appropriate for the infiltration of Ni-gadolinia doped ceria (GDC) electrocatalysts. Compared to conventional Ni-cermet anodes, the nano-sized Ni-GDC particles in our SFCM based electrode significantly improves the cell stability in hydrocarbon gases. We demonstrated a stable long-term operation over a period of 380 h in CH4–containing gas mixtures at 450 °C with a voltage degradation rate of 4% per 1000 h at a constant current of 0.2 A*cm−2. Our results demonstrate a high performance ceramic anode with high stability for low temperature operation.