Novel Tungsten, Molybdenum, and Vanadium Oxides Containing Surfactant Ions

Hydrothermal reaction of tungstic acid, molybdic acid, and vanadium pentoxide with the surfactant template dodecyltrimethylammonium bromide (DTABr) yielded one compound with a Keggin type structure, [C 12 H 25 N(CH 3 ) 3 ] 6 (H 2 W 12 O 40 )· x H 2 O, and two new layered compounds, [C 12 H 25 N(CH 3 ) 3 ] 0.5 (MoO 3.25 ) and [C 12 H 25 N(CH 3 ) 3 ] 2/3 V 2 O 5.33 ·H 2 O. The tungsten salt produced needlelike crystals of a hexagonal shape while the molybdenum and vanadium salts formed layered structures. FTIR analysis of the tungsten salt was consistent with materials containing Keggin anions. The X-ray powder diffraction data of this material were indexed to a monoclinic cell with a = 50.56(4) Å, b = 54.41(4) Å, c = 13.12(1) Å, and β = 99.21°. The observed reflections are consistent with space group C 2/ m . Diffraction data obtained from the molybdenum salt showed a between layer d spacing of ca. 22 Å. The vanadium salt was indexed to a triclinic cell with a = 9.813(3) Å, b = 11.512(3) Å, c = 21.725(5) Å, α = 95.30(1)°, β = 93.82(6)°, and γ = 101.12(8)°, with a layer spacing of 21.6 Å.