New Synthetic Route for Reaching Higher Phase Stabilization in LAMOX‐Based Electrolyte for Solid Oxide Fuel Cells. Issue 13 (6th March 2023)

• Record Type: Journal Article
• Authors: Hchicha, Khouloud; Mhadhbi, Noureddine; Guesmi, Ahlem; Soltani, Taoufik; Hamadi, Naoufel Ben; Naïli, Houcine
• Is Part Of: European journal of inorganic chemistry. Volume 26:Issue 13(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-03-06
• Subjects: fuel cells -- La2Mo2O9 -- LAMOX -- oxide ion conductor -- sulfur; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.202200696
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: S‐substituted La2 Mo2 O9 were synthesized by a solid‐state procedure employing ammonium sulfate (NH4 )2 SO4 as a sulfur source. The synthesized powders were examined using X‐ray diffraction (XRD), thermogravimetric analysis (TGA), infrared, and Raman spectroscopies. The results divulged that the stabilization of the β‐La2 Mo2 O9 polymorph occurred in the interval of sulfur composition 0.1≤y≤0.6. This substitution generates a linear dwindling of the unit cell volume. The decomposition of all substituted samples started above 900 °C with a total weight loss linearly dependent on the sulfur content. Electrical studies confirmed that substituting S 6+ for Mo 6+ suppresses the phase transition of La2 Mo2 O9 and stabilizes the cubic polymorph down to ambient temperature. It was also remarkable that this substitution caused a decrease in the conductivity, and unfortunately, none of the tested compositions allowed exceeding the conductivity of La2 Mo2 O9 . Infrared and Raman spectra confirmed the presence of the characteristic peaks of sulfates and molybdates groups. Abstract : S‐substituted La2 Mo2 O9 were synthesized using a standard solid‐state procedure and examined using X‐ray diffraction (XRD), thermogravimetric analysis (TGA), infrared, and Raman spectroscopies. The stabilization of the high‐temperature β‐La2 Mo2 O9 polymorph occurred in the interval of sulfur composition 0.1≤y≤0.6.