Mitigation of Sulfur Poisoning of Ni/Zirconia SOFC Anodes by Antimony and Tin

Journal Article · Mon Feb 28 00:00:00 EST 2011 · Journal of the Electrochemical Society, 158(4):B424-B429

DOI:https://doi.org/10.1149/1.3552357· OSTI ID:1008219

Marina, Olga A; Coyle, Christopher A; Engelhard, Mark H; Pederson, Larry R

Surface Ni/Sb and Ni/Sb alloys were found to efficiently minimize the negative effects of sulfur on the performance of Ni/zirconia anode-supported solid oxide fuel cells (SOFC). Prior to operating on fuel gas containing low concentrations of H2S, the nickel/zirconia anodes were briefly exposed to antimony or tin vapor, which only slightly affected the SOFC performance. During the subsequent exposures to 1 and 5 ppm H2S, increases in anodic polarization losses were minimal compared to those observed for the standard nickel/zirconia anodes. Post-test XPS analyses showed that Sb and Sn tended to segregate to the surface of Ni particles, and further confirmed a significant reduction of adsorbed sulfur on the Ni surface in Ni/Sn and Ni/Sb samples compared to the Ni. The effect may be the result of weaker sulfur adsorption on bimetallic surfaces, adsorption site competition between sulfur and Sb or Sn on Ni, or other factors. The use of dilute binary alloys of Ni-Sb or Ni-Sn in the place of Ni, or brief exposure to Sb or Sn vapor, may be effective means to counteract the effects of sulfur poisoning in SOFC anodes and Ni catalysts. Other advantages, including suppression of coking or tailoring the anode composition for the internal reforming, are also expected.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1008219
• Report Number(s): PNNL-SA-76341; 25601; AA2530000; TRN: US201106%%332
• Journal Information: Journal of the Electrochemical Society, 158(4):B424-B429, Vol. 158, Issue 4; ISSN 0013-4651
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
36 MATERIALS SCIENCE
ADSORPTION
ALLOYS
ANODES
ANTIMONY
CATALYSTS
COKING
FUEL GAS
MITIGATION
PERFORMANCE
POISONING
POLARIZATION
SOLID OXIDE FUEL CELLS
SULFUR
X-RAY PHOTOELECTRON SPECTROSCOPY
Ni/YSZ anode
SOFC
sulfur poisoning
antimony and tin passivation
bimetallic catalyst
Environmental Molecular Sciences Laboratory