Results 131 to 140 of about 476 (168)

Zn-substituted brownmillerite-type strontium ferrites

Bulletin of the Russian Academy of Sciences: Physics, 2017
New La/Zn substituted strontium ferrites Sr(2 −x)La x [Fe(2 − x)Zn x ]O5, (0 ≤ x ≤ 0.3) with brownmillerite- type structure are obtained and studied via X-ray phase analysis and Mossbauer spectroscopy.
K. V. Pokholok, D. S. Filimonov, M. G. Rozova, O. A. Tyablikov   +3 more
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A Computer Simulation Investigation of Brownmillerite-Structured Ba2In2O5

Journal of Solid State Chemistry, 1997
Abstract Atomistic simulation techniques have been used to investigate the crystal structure and defect energetics of Ba 2 In 2 O 5 . An interatomic potential model was developed that reproduces the orthorhombic brownmillerite structure, with alternating layers of oxygen octahedra and tetrahedra.
C.A.J. Fisher, M.S. Islam, R.J. Brook
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Low-energy excitations in brownmillerites and related oxides

Physica B: Condensed Matter, 2004
It is generally believedthat the glasses andcrystals d iffer very much from each other by their vibrational spectra. However, the crystalline systems with frozen disorder may exhibit the vibrational density of states (DOS) peaked in low-energy region quite resembling to the Bose peak typically observedin glasses.
A.I. Rykov, K. Nomura, T. Mitsui, M. Seto   +3 more
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Ordering of tetrahedral chains in the Sr2MnGaO5 brownmillerite

Journal of Solid State Chemistry, 2003
Abstract Tetrahedral chain ordering in the Sr2MnGaO5 structure is studied using electron diffraction (ED) and high-resolution electron microscopy. The ED patterns show the presence of satellite reflections, which indicate a commensurately modulated structure with a=5.4056(8) A, b=16.171(3) A, c=5.5592(7) A, q =1/2 c * , superspace group ...
Abakumov, A.M., Alekseeva, A.M., Rozova, M.G., Antipov, E.V., Lebedev, O.I., Van Tendeloo, G.   +5 more
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Defect, protons and conductivity in brownmillerite-structured Ba2In2O5

Solid State Ionics, 1999
Abstract Defect energetics of Ba 2 In 2 O 5 have been investigated by atomistic modelling techniques with emphasis on different modes of conductivity. Oxygen Frenkel pairs were found to be the most energetically favourable intrinsic defects and are responsible for oxide ion conductivity in the orthorhombic structure. Formation energies of electronic
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Revealing the Catalytic Heart of Brownmillerites for the Oxygen Evolution Reaction

The Journal of Physical Chemistry Letters
Brownmillerite oxides are a family of metal oxides structurally related to perovskite oxides that have ordered oxygen vacancies. Despite their structural similarity, unlike perovskite oxide, they remain relatively unexplored as oxygen evolution reaction (OER) electrocatalysts.
Anil Kumar, Vikrant Chaudhary, Utkarsh Singh, Tashi Nautiyal, Sujan Sen   +4 more
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Magnetic structure of Sr2Fe2O5 brownmillerite by single-crystal Mössbauer spectroscopy

Journal of Solid State Chemistry, 2013
Abstract In order to determine orientation of the Fe3+ magnetic moments and electric field gradient (efg) axes in the brownmillerite-type strontium ferrite structure for both iron sublattices where the efg tensor is not axially symmetric, the Mossbauer spectra of powdered and oriented single-crystal Sr2Fe2O5 were analyzed by solving the complete ...
Waerenborgh, JC, Tsipis, EV, Auckett, JE, Ling, CD, Kharton, VV   +4 more
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Synthesis and characterization of brownmillerite SrFeO2.5 in nanostructured form

AIP Conference Proceedings, 2015
Synthesis of bulk polycrystalline and nanocrystalline oxygen-deficient SrFeO2.5 compounds, with potential applications as oxygen membranes, has been explored by chemical route to optimize an easy and reproducible method for high yield. The structure of the samples was investigated by X-ray powder diffraction followed by structural refinement. Both bulk
null Suchita, K. Baskar, Shubra Singh
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Evaluation of a brownmillerite oxide as cathode for solid oxide fuel cells

Journal of Power Sources, 2013
Brownmillerite oxide Ca2Fe1.3Mn0.7O5+δ is synthesized and evaluated as a new cathode material for solid oxide fuel cells (SOFCs). The average thermal expansion coefficient (TEC) of Ca2Fe1.3Mn0.7O5+δ is 13.3 ± 0.2 × 10−6 K−1, close to that of the typical electrolyte materials.
Qiang Li, Liping Sun, Xu Zeng, Hui Zhao, Lihua Huo, Jean-Claude Grenier, Jean-Marc Bassat, Fabrice Mauvy   +7 more
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Epitaxial Brownmillerite Oxide Thin Films for Reliable Switching Memory

ACS Applied Materials & Interfaces, 2016
Resistive switching memory, which is mostly based on polycrystalline thin films, suffers from wide distributions in switching parameters-including set voltage, reset voltage, and resistance-in their low- and high-resistance states. One of the most commonly used methods to overcome this limitation is to introduce inhomogeneity.
Susant K, Acharya, Raveendra Venkata, Nallagatla, Octolia, Togibasa, Bo W, Lee, Chunli, Liu, Chang U, Jung, Bae Ho, Park, Ji-Yong, Park, Yunae, Cho, Dong-Wook, Kim, Janghyun, Jo, Deok-Hwang, Kwon, Miyoung, Kim, Cheol Seong, Hwang, Seung C, Chae   +14 more
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