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dc.contributor.authorLópez Vergara, Adrián
dc.contributor.authorVizcaíno-Anaya, Lucía
dc.contributor.authorPorras-Vázquez, José Manuel 
dc.contributor.authorBaldinozzi, Gianguido
dc.contributor.authorDos-Santos-Gómez, Lucía
dc.contributor.authorCanales-Vázquez, J.
dc.contributor.authorMarrero-López, David 
dc.contributor.authorRamírez-Losilla, Enrique 
dc.date.accessioned2023-12-21T11:21:04Z
dc.date.available2023-12-21T11:21:04Z
dc.date.created2023-12-18
dc.date.issued2020-08-03
dc.identifier.urihttps://hdl.handle.net/10630/28458
dc.description.abstractCrystalline La6−xMoO12−δ materials with different lanthanum/molybdenum ratios (0.6 ≤ x ≤ 3.0) have been prepared via a freeze-drying precursor route. The influence of the lanthanum content, sintering temperature, and cooling rate on the phase existence range and polymorphism was evaluated. Lanthanum-rich compounds present three different polymorphs: a cubic (disordered) fluorite and two complex rhombohedral superstructures related to the fluorite. For the first time, the structural resolution of these rhombohedral superstructures, 7 × 7 × 1 and 5 × 5 × 1, has been successfully accomplished by neutron powder diffraction and transmission electron microscopy studies. As the La/Mo ratio decreases, the cubic symmetry is stabilized, although a phase transformation from cubic to monoclinic occurs at a low cooling rate. Impedance spectroscopy measurements under different atmospheres (dry and wet N2 and 5% H2−Ar) show that all materials exhibit mixed proton−electronic conductivity. The n-type electronic conductivity is attributed to Mo6+ reduction and increases for those phases with lower lanthanum content, i.e., for quenched samples, from 5 mS cm−1 for La5.4MoO11.1 to 9.5 mS cm−1 for La4MoO9 at 700 °C in very reducing and wet conditions, which are significantly better than the values published to date for mixed lanthanum tungstates/ molybdates. This makes these materials potential candidates for hydrogen separation membranes.es_ES
dc.language.isoenges_ES
dc.publisherAmerican Chemical Societyes_ES
dc.rightsinfo:eu-repo/semantics/openAccesses_ES
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/4.0/*
dc.subjectSeparación por membranaes_ES
dc.subjectQuímica organometálicaes_ES
dc.subject.otherHydrogen separation membranees_ES
dc.subject.otherLanthanum molybdatees_ES
dc.titleUnravelling Crystal Superstructures and Transformations in the La6−xMoO12−δ (0.6 ≤ x ≤ 3.0) Series: A System with Tailored Ionic/ Electronic Conductivity.es_ES
dc.typeinfo:eu-repo/semantics/articlees_ES
dc.centroFacultad de Cienciases_ES
dc.identifier.doi10.1021/acs.chemmater.0c02673
dc.rights.ccAttribution-NonCommercial-NoDerivatives 4.0 Internacional*
dc.type.hasVersioninfo:eu-repo/semantics/submittedVersiones_ES


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