Fabrication of dialkyldimethylammonium/vanadium oxide gel hybrid Langmuir-Blodgett membranes

A hybrid Langmuir-Blodgett (LB) membrane of dialkyldimethylammonium (DCnA, n=12−18) and vanadium oxide gel was fabricated by compressing a DC n A monolayer on an aqueous vanadium oxide solution. The vanadium oxide gel effectively aggregated in situ as a monolayer on the LB trough and stabilized the ammonium monolayer by electrostatic interaction. The hybrid LB monolayer, transferred onto a silicon wafer, had a smooth surface, with less than 1-nm roughness over a 1 μm × 1 μm square area. Multilayered membranes, prepared by repeated transfer of monolayers, showed sharp XRD patterns, assigned as an ordered bilayer-type structure with 2.9–4.8 nm thickness.