Strontium iron molybdenum oxide as electrocatalyst for nitrous oxide reduction in solid oxide fuel cells

• Type: Article in International Scientific Journal
• Date: 2024

Authors

Holz, LIV (Author) Other; Loureiro, FJA (Author) Other; Graça, VCD (Author) Other; Mikhalev, SM (Author) Other; Fernandes, C (Author) Other; Adélio Mendes (Author) FEUP; Fagg, DP (Author) Other

Journal

Title: International Journal of Hydrogen Energy

Vol. 54

Pages: 25-36

ISSN: 0360-3199

Publisher: Elsevier

Indexing

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Other information

Authenticus ID: P-00Y-J3K

DOI: 10.1016/j.ijhydene.2023.05.251

Abstract (EN): Nitrous oxide (N2O) is an environmentally damaging gas and alternative methods for its abatement are needed. In this work, we developed an electrochemical route using the mixed ionic electronic conductor Sr2Fe15Mo05O6-delta (SFMO) as electrocatalyst for N2O reduction in the temperature range of 600-800 degrees C, at ambient pressure, for application in Solid Oxide Fuel Cells (SOFCs). The electrode mechanism, studied by electrochemical impedance spectroscopy (EIS), is discussed to involve a competition between both O-2 and N2O species, particularly at lower temperatures, where N2O thermal decomposition is lower. In terms of electrocatalytic properties, galvanostatic transients were used to assess N2O electroreduction on the SFMO electrode. The results showed that, after cathodic polarization, the N2O conversion increases. In particular, a highest Faradaic efficiency (|Lambda|) of 3.94 was obtained at 600 degrees C. The reversibility of the mechanism was also assessed, and the results showed that the reaction rate returns to its open circuit value upon current interruption. This work indicates, therefore, that the electrochemical promotion of N2O reduction can be an attractive tool to be implemented for the reduction of this environmentally damaging gas in SOFC systems.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12