Nanocomposite Hydrogen-Bonded Multilayer Ultrathin Films by Simultaneous Sexithiophene and Au Nanoparticle Formation

Terthiophene-functionalized poly(4-vinylpyridine) (PVP3T) was incorporated successfully as a reductant to form Au nanoparticles within hydrogen-bonded complexed multilayer thin films. By employing polymer pendant terthiophene moieties, this eliminated the need for an external reducing agent. The redox reaction with HAuCl 4 yielded Au nanoparticles simultaneously with the formation of electrooptically active sexithiophene units. The nanocomposite films were characterized by TEM, XPS, UV−vis, photoluminescence, FT-IR, and ellipsometry measurements. The TEM images confirm unequivocally the formation of well-dispersed nanoparticles within the multilayer structure with a range of size distributions dependent on the preparation conditions. Interestingly, we observed the growth of dendritic nanostructures within the PVP3T/poly(acrylic acid) multilayers with modifications to the preparation procedure. On the basis of these results, this method yields a unique approach for the fabrication of nanocomposite multilayer heterostructures comprised of metallic nanoparticles and conjugated oligomers with interesting nanostructural and spectroscopic properties.