Catalysis in SC-SOFCs

Despite the numerous investigations on understanding SC-SOFCs over the past 20 years, little attention has been paid to the crucial role of catalysis in such 

Recently, Savoie etal. [24] reported an extensive investigation on catalysis in SC-SOFCs with Ni-YSZ (yttria-stabilized zirconia) anodes. Their investigations were performed on three different half-cells exposed at various temperatures to a methane-air gas mixture. The detected outlet gases contained CO and H2, but also CO2, suggesting that the complete oxidation reaction also occurred. Furthermore, at a fixed gas flow rate, the outlet gas composition was found to depend on both Rmix and the thickness of the anode. At 600 °C and Rmix = 1-2, 33% of methane was catalytically converted on a thin anode (0.05 mm), and more than double on a thick anode (1.52 mm). An increase in temperature led to an increase in methane conversion. At 800 °C and R ix = 1-2, the yield of H2 was 14 and 38% for thin and thick anodes, respectively. The production of syngas was significantly reduced at lower temperatures. From this study, it is obvious that the optimization of SC-SOFC systems requires extensive catalytic studies on the electrode materials. 

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