Synthesis of electro-active membranes by chemical vapor deposition (CVD) process

Abstract

In the past two decades, many research is being carried out on coating of textile membranes with conductive polymers. In order to functionalize the textile membranes, coating of different intrinsically conductive polymers can be applied on these membranes through appropriate coating techniques like electrochemical polymerization, wet chemical oxidation and chemical vapor deposition (CVD). Noticeably, CVD process is one of the most suitable and environment friendly technique. In this research, microporous polyester and polytetrafluoroethylene (PTFE) membranes were coated with conductive poly(3,4-ethylenedioxythiophene) (PEDOT) by CVD process in the presence of ferric(III)chloride (FeCl3) used as an oxidant. Polymerization of PEDOT on the surface of membranes and pore size was examined by optical microscope and scanning electron microscopy (SEM). Structural analysis investigated with ATR-FTIR, which revealed the successful deposition of PEDOT on membranes without damaging their parent structures. The amount of PEDOT in PEDOT-coated polyester and PTFE membranes was explored with the help of thermogravimeteric analysis. Electrical resistance values of PEDOT-coated membranes were measured by two probe method. The effect of different electrolyte solutions such as, distilled H2O, Na2SO4, HCl, and H2SO4 on electrical properties of produced conductive membranes was investigated after dipping for certain period of time. It was found that membranes dipped in H2SO4 show very low electrical resistance values, i.e. 0.85 kΩ for polyester membrane and 1.17 kΩ for PTFE membrane. The obtained PEDOT-coated electro-active membranes may find their possible utility in fuel cells, enzymatic fuel cells, and antistatic air filter applications. Copyright © 2014 John Wiley & Sons, Ltd.