Ellipsometric studies of polyaniline growth and redox cycling

Abstract

Ellipsometry has been used to characterise the growth of polyaniline films on platinum and gold electrodes by potential cycling. Analysis of the time evolution of the ellipsometric parameters allowed continuous monitoring of the growth process, and subsequent measurements of the changes in optical properties during oxidation and reduction of the PANI film were related to the electrochemical behaviour. Spectroscopic ellipsometry has been used to evaluate n and k values of the film for differing degrees of oxidation. Frequency-resolved transmission measurements have been used to show that the periodic electrical and optical responses of the polyaniline film are directly related.