Template-Directed Synthesis of Micro and Nano-Structures of Functional Conducting Copolymers by Oxidative Chemical Vapor Deposition

Template-directed synthesis of micro and nano-structures of functional conducting copolymers by oxidative chemical vapor deposition

Dhiman Bhattacharyya, and Karen K. Gleason*

Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139

Abstract:

Template-directed syntheses of inorganic and organic materials are becoming very popular because it is easy to control the desired structures in the products. Micro and nanostructures are important because they provide very high surface area to volume ratio. It increases the interfacial area of the surfaces. Thus synthesized increased surface areas have many applications, for example, to increase the sensitivities of sensors, performances of the photovoltaic cells. Previously, nano and micro-structures made of conductive polymers have been reported. However, they were free floating nanostructures of conductive polymers.  In this work, we present a single step preparation of micro-tubules and nanoforests of functional conductive copolymers by oxidative chemical vapor deposition (oCVD) process at low temperature. Here, 3,4-ethylenedioxythiophene (EDOT) and 3-substituted thiophene monomers were employed to synthesize these structures. Iron chloride was used as an oxidant during the vapor phase polymerization step, as well as a dopant in the polymeric system in order to make it conductive. The copolymeric films were characterized by FT-IR, UV-Vis and X-ray photoelectron spectroscopies and 4-point probe measurements and SEM. The available functional groups in the copolymers were used for further derivatization reactions.