T. Yamaki et al., Formation of hybrid monolayers and Langmuir-Blodgett-type multilayers fromammonium cations and TiO2 crystalline nanosheets, THIN SOL FI, 393(1-2), 2001, pp. 154-160
A novel hybrid monolayer composed of ammonium cations and TiO2 crystalline
nanosheets was formed at an air-water interface. We employed, as the subpha
se under the monolayer, stable colloidal suspensions obtained by exfoliatin
g a lepidocrocite-type layered titanate, H(x)Ti(2-x/4)square O-x/4(4).H2O (
x similar to 0.7; square, vacancy) into elementary host layers. Surface pre
ssure-area isotherms demonstrated that spreading molecules of dioctadecyldi
methylammonium bromide (DODAB) on the suspensions resulted in complexation
of DODAB with the exfoliated single layers of quasi-TiO2. The hybrid monola
yer was quantitatively transferred onto solid substrates by the Langmuir-Bl
odgett (LB) technique to form a multilayer film. UV-Visible absorption spec
tra and X-ray diffraction measurements confirmed that the film possessed a
DODAB/TiO2 alternating structure with a repeating unit of 3.4 nm. (C) 2001
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