Study Of Functional Films Based On Polyoxometalates

Inorganic-organic nanocomposite film materials with optical,electrical and magnetic properties are one of the research focuses in contemporary materials science. The studies on inorganic-organic composite functional films of polyoxometalates have drawn more and more attention owing to their potential applications in luminescence, photochromism, magnetism, electrics and catalysis.This work deals with the preparation of the polyoxometalate-based functional film materials.The functional films of{PEI/(α-SiW12/MB)n}, {PEI/(a-PMo12/MB)n} and{PEI/(P2W17/Ru(Bphen))n}were prepared by layer-by-layer technology. The components, structures and properties of these films were characterized by UV-vis spectra, X-ray photoelectron spectrum (XPS), atomic force microscopy (AFM), Fluorescence spectra (FL) and cyclic voltammetry (CV).These measurements showed that the above-mentioned inorganic-organic components were incorporated into the composite films and their original structures and properties remained in the films. The growth processes of the assembled films were quantitative and highly reproducible from layer to layer. The surfaces were smooth and were dispersed with uniform spherical particles.The films of{PEI/(a-SiW12/MB)n} and{PEI/(a-PMo12/MB)n} show inhibition against the Escherichia coli. This result shows potential application of the{PEI/(POMs/MB)n} multilayer films in antibacterial materials. And we discuss the mechanism of antibacterial activities. The film of{PEI/(P2W17/Ru(Bphen))n} shows the characteristic luminescence of Ru(Ⅱ)and represents electro-catalytic activity towards bromate ion and nitrite.