ELECTROCHROMIC PROPERTY OF ELECTROCHEMICALLY POLYMERIZED TRIS(PHENANTHROLINE DERIVATIVE)-IRON(II III) COMPLEX FILM/

A new film of the iron complexes with 4,7-bis ((2-hydroxyphenyl) methy laminosulfonylphenyl)-1, 10-phenanthroline (HPP) ligand is prepared on the electrode surfaces of In-Sn oxide conducting glass (ITO) by elect rooxidative polymerization. The resulting film shows a well-defined re versible voltammogram corresponding to the redox reaction of the Fe (I I/III) complexes, which have the electrochromic property of red and co lorless with the difference of oxidation states. Reversible electrochr omic responses between red and colorless were obtained in aqueous and nonaqueous solutions when the appropriate potentials are applied to th e film coated electrode. The response rate of the color change was wit hin 0. 5 sec for the film of the thickness PHI = 300 nm. The electron transfer rate through the film can be treated apparently with diffusio nal process. The apparent diffusion coefficients for the electron tran sfer process within the film are evaluated as (1-2) X 10(-8) cm2s-1 fo r coloring and bleaching processes of the [Fe (HPP)3]2+/3+ film by pot ential-step chronoamperometric and chronocoulometric methods.