Performance studies of copper–iron/ceria–yttria stabilized zirconia anode for electro-oxidation of butane in solid oxide fuel cells

Abstract

Addition of second metal to Cu is useful for electro-oxidation of hydrocarbons in solid oxide fuel cells (SOFC). In this work, electro-catalysts based on Cu–Fe bimetallic anode for use of both H2 and n-C4H10 in SOFC is prepared by wet impregnation method into a porous CeO2–YSZ matrix. The prepared Cu–Fe/CeO2–YSZ anodes are then characterized by thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), elemental dispersive X-ray (EDX) and scanning electron microscopy (SEM). Carbonaceous deposits formed on Cu–Fe/CeO2–YSZ anodes after exposure to n-C4H10 are studied using a combination of i–V characteristics and TGA measurements. It is observed that the addition of Fe to Cu in CeO2–YSZ cermet anode enhance the performance in H2 and n-C4H10 fuels. The performance of cell having molar ratio of Cu–Fe of 1:1 in Cu–Fe/CeO2–YSZ anode shows power density of 240 mW cm−2 and 260 mW cm−2 in n-C4H10 and in H2 after n-C4H10 flow at 800 °C. The i–V curve shows that the conductivity of the anode improves after exposure to n-C4H10. No apparent degradation in performance is observed after n-C4H10 flow except for carbon fibre formation indicating Cu–Fe bimetallic is worth considering as an anode for direct butane SOFC.