| 초록 |
The H2S tolerance and stability of a Sm0.2Ce0.8O2-δcoating on the Ni/YSZ anode pore wall surface was investigated. The sulfur poisoning mechanisms were studied for various H2S concentrations(0-100ppm) and temperatures(600-700C)under both OCV and current-loading conditions. The unmodified Ni/YSZ anode under current-loading conditions, the cell performance decreased with the introduction of H2S, as the sulfur adsorbed at the ERSs. The SDC-modified Ni/YSZ anode under the OCV conditions, the governing mechanism of the H2S poisoning was the formation of Ce2O2S with low oxygen ion conductivities. The SDC-modified anode under current-loading conditions, the MIEC of the SDC allowed the electrochemical reactions to occur mainly at the SDC/fuel interface. With these conditions, the adsorbed sulfur was removed by the electrochemical oxidation. The decrease in the sulfur poisoning effect resulted in stable cell performances at 500ppm of H2S over 800h. |
