title: Covalent layer-by-layer assembly of redox-active polymer multilayers.
abstract: Poly(ferrocenyl(3-bromopropyl)methylsilane) and poly(ethylene imine) are employed in a layer-by-layer deposition process to form covalently connected, redox-active multilayer thin films by means of an amine alkylation reaction. The stepwise buildup of these multilayers on silicon, ITO, and quartz substrates was monitored by UV-vis absorption spectroscopy, Fourier transform infrared spectroscopy (FTIR), static contact angle measurements, surface plasmon resonance (SPR), atomic force microscopy, ellipsometry, and cyclic voltammetry, which provide evidence for a linear increase in multilayer thickness with the number of deposited bilayers. Upon oxidation and reduction, these covalently interconnected layers do not disassemble, in contrast to poly(ferrocenylsilane) (PFS) layers featuring similar backbone structures that are held together by electrostatic forces. The PFS/PEI multilayers are effective for the electrochemical sensing of ascorbic acid and hydrogen peroxide and show improved sensing performance at higher bilayer numbers. These covalently linked layers are readily derivatized further and can therefore be regarded as a versatile platform for creating robust, tailorable, redox-active interfaces with applications in sensing and biofuel cells.
authors: Department of Materials Science and Technology of Polymers, University of Twente, MESA+ Institute for Nanotechnology, Enschede, The Netherlands.
authors: Xueling
authors: X
authors: Feng
authors: Aysegul
authors: A
authors: Cumurcu
authors: Xiaofeng
authors: X
authors: Sui
authors: Jing
authors: J
authors: Song
authors: Mark A
authors: MA
authors: Hempenius
authors: G Julius
authors: GJ
authors: Vancso
mesh_terms: D018625:Microscopy, Atomic Force; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D020349:Surface Plasmon Resonance
chemical_list: D011108:Polymers