Formation of polymer films containing multivalent metal cations by stepwise alternate adsorption of metal cations and polyanions

Abstract

Self-assembled multilayer films, in which molecular polyelectrolyte building blocks are held together by complexed multivalent metal cations, were prepared successfully via sequential layer-by-layer adsorption reactions. To form such films, rare-earth cations (Gd3+, Er3+, Nd3+), and poly(styrene sulfonate)-Na were used. The characterization of mutilayer built-up films, formed on the oxidized silicon and quartz substrates was carried out by atomic force microscopy, Fourier transform infrared spectroscopy, UV–Vis spectroscopy, X-ray diffraction. Gadolinium content in the material and magnetic properties of Gd-containing films were characterized by electron paramagnetic resonance technique. The data obtained indicate closely packed and homogeneous structure of built-up films with high content of rare-earth cations. Simple layer-by layer film growth procedure in this method, allows for the systematic effective nanometer-scale level single-layer control of chemical content, composition, functionality, metal cation complexes structure and film thickness. This structure, in turn, determines film properties of interest (optical, electronic, chemical, mechanical, magnetic etc.). As a result, such polymer rare-earth-doped film materials can be perspective for various photonic and other applications.