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

摘要

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 H_2 and n-C_4H_(10) in SOFC is prepared by wet impregnation method into a porous CeO_2-YSZ matrix. The prepared Cu-Fe/CeO_2-YSZ anodes are then characterized by thermo-gravimetric analysis (TCA), X-ray diffraction (XRD), elemental dispersive X-ray (EDX) and scanning election microscopy (SEM). Carbonaceous deposits formed on Cu-Fe/CeO_2-YSZ anodes after exposure to n-C_4H_(10) are studied using a combination of i -V characteristics and TGA measurements. It is observed that the addition of Fe to Cu in CeO_2-YSZ cermet anode enhance the performance in H_2 and n-C_4H_(10) fuels. The performance of cell having molar ratio of Cu-Fe of 1:1 in Cu-Fe/CeO_2-YSZ anode shows power density of 240 mW cm~(-2) and 260 mW cm~(-2) in n-C_4H_(10) and in H_2 after n-C_4H_(10) flow at 800 C. The i-V curve shows that the conductivity of the anode improves after exposure to n-C_4H_(10) No apparent degradation in performance is observed after n-C_4H_(10) flow except for carbon fibre formation indicating Cu-Fe bimetallic is worth considering as an anode for direct butane SOFC.