Copper–terbia and copper–gadolina anodes for direct hydrocarbon solid oxide fuel cells: A fundamental comparison of their physicochemical features and performances

Copper–terbia and copper–gadolina supported electrolyte SOFCs have been prepared by using standard procedures; such as, tape casting, dual tape casting, painting and impregnation. Anode XRD patterns analysis lead to the following chemical formulas: TbO1.823–CuO–Zr0.8Y0.2O1.9 and Gd2O3–CuO–Zr0.8Y0.2O1.9. Since TPR profiles and cell performances are fundamentally based on solid state RedOx reactions, a comparative analysis could suggest that there is an apparent correlation between them. This first approach may be considered as the basis of a simple methodology to predict SOFC anodes performances. Cu–TbO2 SOFC performance depends on the hydrocarbon nature (toluene < n-heptane < cyclohexane < 1-hexene), the cell behaviour (in term of power density) is improved when light hydrocarbons (those which have low carbon/hydrogen ratio content) are fed. Furthermore, the performance is improved by successive anode reactivations using hydrogen.