Metastable hexagonal molybdates: Hydrothermal preparation, structure, and reactivity

Journal Article · Sat Jul 01 00:00:00 EDT 1995 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1006/jssc.1995.1280· OSTI ID:146440

Guo, J; Zavalij, P; Whittingham, M S ^[1]

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1. State Univ. of New York at Binghamton, NY (United States)

Hydrothermal treatment of acidified M{sub 2}MoO{sub 4} solutions at 150{degrees}C for 3 days leads to a range of structures depending on the metal M. Hexagonal molybdates with the general formula (M{sub y} {center_dot} zH{sub 2}O)Mo{sub 6{minus}x}O{sub 13{minus}x}H{sub 4{minus}y} are formed when M is a small cation, such as Na{sup +}, NH{sup +}{sub 4}, and Ag{sup +}. These molybdates crystallize as hexagonal rods and have the space group P6{sub 3}/m. The open structure of these hexagonal molybdates both allows the M ions in the tunnels to be readily mobile and permits the ready intercalation of additional cations such as hydrogen and lithium. Upon continuous ion exchange of sodium molybdate with 6 N HNO{sub 3}, a new hydrate, MoO{sub 3} {center_dot}O.6H{sub 2}O, was formed; subsequent dehydration of this hydrate results in the formation of a new hexagonal modification of {open_quotes}MoO{sub 3}.{close_quotes} The structural features, thermal properties, diffusion, and reactivity of these phases have been determined and compared with phases synthesized by other methods.

• Sponsoring Organization: USDOE
• OSTI ID: 146440
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 2 Vol. 117; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
AMMONIUM COMPOUNDS
CHEMICAL REACTIONS
CRYSTAL STRUCTURE
HYDRATES
HYDROTHERMAL SYNTHESIS
ION EXCHANGE
MOLYBDATES
SILVER COMPOUNDS
SODIUM COMPOUNDS