Sulfur-poisoned Ni-based solid oxide fuel cell anode characterization by varying water content

The 0.2% hydrogen sulfide (H2S) poisoning of Ni/YSZ anode-supported solid oxide fuel cells (SOFCs) is investigated by varying water content in fuel. The degradation extent of the cell voltage decreases with increasing water content (from 0% to 10%). Water can be generated at the anode side through an electrochemical reaction, and the content of water product augments upon the addition of fuel. However, our results indicate that an increase in fuel utilization significantly aggravates H2S poisoning behavior. The results of X-ray analysis suggest that the presence of water in fuel cannot affect the final forms of nickel sulfides, but microstructural inspection reveals different attack modes upon the injection of vapor (from 0 to 10%) into fuel containing 0.2% H2S.

Research highlights▶ The effect of water content in fuel on the H2S poisoning Ni-based solid oxide fuel cell was confirmed in the original experimental course. ▶ The contaminated materials were analyzed using the EDS and XRD techniques and two new Ni–S phases was detected because of the high concentration of H2S fed to the fuel. ▶ The specific morphology was observed for the poisoned surface of Ni–YSZ anode.