Low temperature synthesis and characterization of Na–M–(O)–F phases with M=Ti, V

Journal Article · Sun Mar 15 00:00:00 EDT 2015 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2015.03.006· OSTI ID:22475667

Nava-Avendaño, Jessica ^[1]; Ayllón, José A. ^[2]; Frontera, Carlos; Oró-Solé, Judith ^[1]; Estruga, Marc ^[2]; Molins, Elies ^[1]

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1. Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, E-08193 Bellaterra, Catalonia (Spain)
2. Departament de Química, Universitat Autònoma de Barcelona, Campus UAB, E-08193 Bellaterra, Catalonia (Spain)

Na{sub 5}Ti{sub 3}O{sub 3}F{sub 11} was prepared by the microwave assisted method, and presents a chiolite related structure with cell parameters a=10.5016(5), b=10.4025(5), and c=10.2911(5) Å and Cmca (no. 64) space group. From solvothermal synthesis at 100 °C the cryolite Na{sub 3−δ}VO{sub 1−δ}F{sub 5+δ} was prepared, which crystallizes in the monoclinic system with a=5.5403(2), b=5.6804(2), c=7.9523(2) Å, β=90.032(7)° cell parameters and P2{sub 1}/n (no. 14) space group. Under similar synthesis conditions but with higher HF concentration the chiolite-type phase Na{sub 5−δ}V{sub 3}F{sub 14} was achieved, which exhibits a=10.5482(2), b=10.4887(1) and c=10.3243(1) Å cell parameters and Cmc2{sub 1} (no. 36) space group. A single crystal also having the chiolite structure was synthesized at 200 °C which exhibits tetragonal symmetry (a=7.380(3) and c=10.381(11) Å and space group P4{sub 2}2{sub 1}2 (no. 94)). Bond valence sum indicates that it contains V{sup 4+} and therefore can be formulated as Na{sub 5}V{sub 3}O{sub 3}F{sub 11}. - Graphical abstract: Na{sub 5}M{sub 3}(O,F){sub 14} with M=Ti and V having chiolite structure and Na{sub 3−δ}VO{sub 1−δ}F{sub 5+δ} cryolite were prepared by means of microwave-assisted and solvothermal synthesis. - Highlights: • Na{sub 5}Ti{sub 3}O{sub 3}F{sub 11} chiolite was prepared by a microwave assisted method and characterized. • Na{sub 3−δ}VO{sub 1−δ}F{sub 5+δ} and Na{sub 5−δ}V{sub 3}F{sub 14} were prepared by solvothermal synthesis. • The compounds were structurally characterized by diffraction techniques. • O/F distribution was estimated by applying Pauling’s second rule.

• OSTI ID: 22475667
• Journal Information: Journal of Solid State Chemistry, Vol. 226; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CONCENTRATION RATIO
LATTICE PARAMETERS
MICROWAVE RADIATION
MONOCLINIC LATTICES
MONOCRYSTALS
ORTHORHOMBIC LATTICES
OXYFLUORIDES
SODIUM COMPOUNDS
SYNTHESIS
TEMPERATURE DEPENDENCE
TITANIUM COMPOUNDS
VALENCE
VANADIUM COMPOUNDS
VANADIUM IONS