Influence of Y-substitution on phase composition and proton uptake of self-generated Ba(Ce,Fe)O_3−δ–Ba(Fe,Ce)O_3−δcomposites

Abstract

Substitution with Y affects phase formation and the local cation stoichiometry of the Ce-rich and Fe-rich phases of BaCe1−(x+z)FexYzO3−δ self-generated composites. This is of particular importance for the water uptake in these compounds.

Interface Diffusion and Compatibility of (Ba,La)FeO3−δ Perovskite Electrodes in Contact with Barium Zirconate and Ceria

“…We will make use of these concepts in the discussion of the present results. Such aspects have been recognized to play a role in the dopant distribution in the BaFeO 3 –BaCeO 3 system …”

“…Such aspects have been recognized to play a role in the dopant distribution in the BaFeO 3 −BaCeO 3 system. 41 In addition to the driving forces, the amount of interdiffusion is determined by the mobilities of the cations in and between the respective oxide phases. In the materials considered here (oxides with perovskite and fluorite structure), cation diffusion is typically slow, with bulk diffusion being orders of magnitude lower than diffusion along grain boundaries and interfaces, as shown in Figure S1 (all diffusion coefficients are self/tracer diffusion coefficients; if suitable isotopes are unavailable, chemically similar "impurity cations" were used).…”

Electrokinetic Insights into the Triple Ionic and Electronic Conductivity of a Novel Nanocomposite Functional Material for Protonic Ceramic Fuel Cells

“…The phase separation of BCCFZ into a rhombohedral‐cubic structure could be due to the wide difference between the ionic radii of the two key B‐site elements (Ce and Co) based on their stoichiometric composition during the synthesis of the BCCFZ (4411) nanocomposites. [ 23 ] The Ce and Co with an oxidation state of +4 (coordination VI) have an ionic radius of 0.87 and 0.53 nm, respectively, based on Shannon estimation. [ 24 ] From the Rietveld refinement results, the rhombohedral phase (space group = R‐3c, JCPDS: 75‐0431) is the dominant phase (60 wt%) with the lattice parameters a = b = 6.167753 Å and c = 15.056063 Å while the cubic phase (40 wt%, space group = Pm‐3m, JCPDS: 75‐0227), has the lattice parameters a = b = c = 4.1060143 Å.…”

Perovskites for protonic ceramic fuel cells: a review

“…The hybrids were composed of proton and electron co-conducting phases, which could facilitate the ionic transport in electrodes for PCFCs. 197 Very recently, we conducted several valuable studies in this research area. For example, Song et al synthesized a multi-phase cathode in accordance with stoichiometric BaCo 0.7 (Ce 0.8 Y 0.2 ) 0.3 O 3− δ (BCCY).…”