Sorry, you need to enable JavaScript to visit this website.

Electrochemical impedance study of the poisoning behaviour of Ni-based anodes at low concentrations of H2S in an MCFC

TitleElectrochemical impedance study of the poisoning behaviour of Ni-based anodes at low concentrations of H2S in an MCFC
Publication TypeArticolo su Rivista peer-reviewed
Year of Publication2012
AuthorsDevianto, H., Simonetti E., McPhail S.J., Zaza F., Cigolotti V., Paoletti C., Moreno A., La Barbera A., and Luisetto I.
JournalInternational Journal of Hydrogen Energy
KeywordsActive site, Applied loads, Biogas, Carbon dioxide, Cerium compounds, Cerium oxides, Chromium, Coating layer, Coatings, Dip coating, EIS, Electrochemical impedance, Electrochemical impedance spectroscopy, Electrochemical studies, Low concentrations, Metal surfaces, Metallic compounds, Molten carbonate, Molten carbonate fuel cells (MCFC), Potential solutions, Protective layers, Rare earth elements, Rare-earth metal oxide, Thin layers

The effect was investigated of low H2S concentrations, simulating biogas impurity, on the poisoning behaviour of a Ni-based, molten carbonate fuel cell anode. A conventional Ni-Cr anode was coated with ceria using dip coating to form a rare earth metal oxide thin layer on the surface of the anode. Electrochemical studies of the Ni-based samples were performed in symmetric cells under anode atmosphere (H2, CO2, H 2O and N2 as balance) with 2, 6, 12, and 24 ppm of H 2S by means of electrochemical impedance spectroscopy. The recorded data showed that the poisoning resistance was enhanced at low coating percentages of ceria; effects depend on H2S concentration and the applied load. These results were confirmed by electrochemical impedance tests where the cerium oxide addition appears through stable polarization behaviour up to 6 ppm of H2S, particularly in the mass transfer region. The protection is explained by the depression of poisoned Ni active sites and formation of a protective layer to the metal surface. The ceria coating layer is a potential solution to reduce H2S poisoning of MCFCs fuelled with biogas. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


cited By 10

Citation KeyDevianto201219312