ORGANIC/INORGANIC HYBRID STRUCTURES BY MOLECULAR ASSEMBLY

Abstract

This thesis is focused on formation of nanostructured, regio-regular conducting polythiophene films by covalent binding and Langmuir-Blodgett (LB) assembly to fabricate organic/inorganic hybrid structures. Multilayers of polythiophene have been formed on with substrate-film and layer-to-layer links established by covalent bonding. The covalently bound nanostructured films possessed uniformity, good thermal and chemical stabilities and good electrical characteristics. Langmuir-Blodgett (LB) assembly has been adapted to fabricate molecular layers containing blends of an amphiphilic regio-regular, ether-terminated polythiophene with a polyalkylthiophene. Hybridization has been accomplished by introducing Au nanoparticles into the covalent and LB polythiophene films by making use of electrostatic and chemisorptive interactions. Polythiophenes were also assembled on one-dimensional ZnO nanorods synthesized by a low temperature and cost effective solution based two-step approach. The nanorods were vertically oriented and densely packed exhibiting a hexagonal wurtzite structure. These hybrid structures showed enhancement in the photoresponse and electrical conductivity upon light exposure on the film.