Studying the Sulfur Poisoning Mechanism of Solid Oxide Fuel Cells by Means of Patterned Nickel/Yttrium-Stabilized Zirconia Electrodes

Abstract

Sulfur causes Ni-based ceramic anode poisoning and thus shortens the life of the cell. Therefore, it is important to clarify the mechanism of sulfur poisoning to improve cell performance and lifetime. However, there is still some controversy about the mechanism of sulfur poisoning. In this work, Ni-patterned electrodes were used for electrochemical experiments to investigate the mechanism of sulfur poisoning under different operating parameters. First, the Ni pattern electrode is operated in H2 fuel containing H2S with the H2S concentration gradually increasing from 5 ppm to 50 ppm. As the concentration of H2S increases, the electrode performance decreases faster. The effect of high oxygen ion flux on the degree of sulfur poisoning was investigated by regulating the operating current of the Ni-patterned electrode SOFC. The results show that the operating current has a large effect on poisoning. This work provides empirical evidence for the mechanism of Ni/YSZ anode sulfur poisoning, and a possible mechanism for Ni/YSZ anode poisoning under sulfur exposure conditions was established.