Muñoz Gil, DanielBoulahya, KhalidSantoyo, María SantamariaAzcondo, TeresaAmador, Ulises2024-01-222024-01-222021Daniel Muñoz Gil, Khalid Boulahya, María Santamaria Santoyo, M. Teresa Azcondo, and Ulises Amador Inorganic Chemistry 2021 60 (5), 3094-3105 DOI: 10.1021/acs.inorgchem.0c033910020-166910.1021/acs.inorgchem.0c03391https://hdl.handle.net/20.500.14352/94287The effects of the contents of iron and cobalt on the crystal structure, oxygen content, thermal expansion coefficient, and electrical−electrochemical properties of materials Eu2SrCoxFe2−xO7−δ (x = 0.50 and 1.00) are reported. These oxides are well-ordered new members of the Ruddlesden−Popper series (Eu,Sr)n+1(Co,Fe)nO3n+1 system with n = 2 as determined by selected area electron diffraction and high-resolution transmission electron microscopy and X-ray diffraction studies. The two materials are semiconductors of p-type, with much higher total conductivity under working conditions for the low cobalt compound, Eu2SrCo0.50Fe1.50O7−δ. Composite cathodes prepared with this oxide present much lower area-specific resistance values (0.08 Ω·cm2 at 973 K in air) than composites containing Eu2SrCo1.00Fe1.00O7−δ (1.15 Ω·cm2). This significant difference is related to the much higher total conductivity and a sufficiently high content of oxygen vacancies in the Fe-rich phase. The excellent electrochemical performance of Eu2SrCo0.50Fe1.50O7−δ with low cobalt content, which shows one of the lowest area-specific resistance reported so far for a Ruddlesden−Popper oxide, makes it a good candidate for application as a cathode material for solid oxide fuel cells at intermediate temperatures in real devices.engjournal articlehttps://doi.org/10.1021/acs.inorgchem.0c03391restricted access546Química inorgánica (Química)23 Química