Ni/YSZ ANODE MODIFIED BY IMPREGNATED CeO2 FOR A SOFC WITH HYDROGEN AND METHANE FUEL

摘要

CeO2 was an efficient catalyst material as a Solid Oxide Fuel Cell (SOFC) electrode because of its high oxygen storage capacity and catalytic activity. In this paper, Ni/YSZ catalyst electrode was fabricated by tape casting method, which was modified by impregnated CeO2.The function of added CeO2 on Ni/YSZ anode was investigated by discharge testing. CeO2 formed a porous layer on Ni grains to enlarge TPB and augment oxygen ion channels from SEM images, and the impregnated CeO2 improved anode performance significantly. The optimal content of impregnated CeO2 in Ni/YSZ anode was 2wt%. The maximum power density of the cell with this anode were 378mW/cm2 for H2 fuel and 238mW/cm2 for CH4 fuel at 1073K.The electrochemical impedance spectra (EIS) was applied to characterize the cell reaction resistance. From the impedance analysis results, anode polarization determined the low-frequencies arc. CH4 decomposition on Ni-YSZ and CeO2-Ni-YSZ anodes were proceeding, which indicated that impregnated CeO2 could reduce carbon formation from CH4 decomposition.