Abstract: The electrochemical polymerization of thionine in the aqueous acetic solution has been carried out using cyclic voltammetry. Polythionine is a blue material. Its color can be quickly changed by applied potential. Polythionine has a good electrochemical reversibility, stability and a fast charge transfer ability in the solution of 0.50 mol•dm－3 HCl to the solution of acetate of pH 6.0. Visible and FTIR spectra of polythionine have been presented in this paper. Based on FTIR spectra, a suggestion for mechanism of polymerization of thionine is presented.

Key words: Thionine, Electrochemical polymerization, Spectra of polythionine, 　 Electrochemical properties