Controlling the morphology of electrochemically deposited poly(3-methylthiophene) films by electrode rotation

Abstract

An investigation of the influence of electrode rotation on the electrochemical deposition of poly(3-methylthiophene) and the morphology and properties of the resulting films has been performed which confirms that soluble intermediates play a significant role in polymer deposition. It appears that polymer deposition takes place through two simultaneous processes, that is, propagation at the ends of polymer chains in the polymer matrix and the precipitation of oligomeric/polymeric species from solution. Precipitation dominates on a stationary electrode at long times and leads to porous, uneven films. Dense compact films are formed at high rotation rates (e.g. 1600 rpm). Impedance spectroscopy has revealed that films prepared at high rotation rates are much less permeable than those prepared on stationary electrodes.