Study and development of conducting polymer-based electrochromic display devices

The electrochromic response of conducting polypyrrole (PPy)/Prussian blue ( PB) and conducting polyaniline (PANI)/Prussian blue (PB) composite films ha s been studied in different electrolytes such as KCl, LiClO4, K2SO4, KNO3, KI/I-2, etc, by depositing the PB films on top of the conducting PPy and PA NI films-all prepared by electrochemical methods. The results show that the use of PB on PPy and PANI not only yields high contrast but also extends t he electrochromic response to a wider region of the visible spectrum, thus working as a sensitizer for improving the electrochromic response of the co nducting PPy and PANI. These electrochromic films have been characterized b y other physicochemical characterization techniques such as cyclic voltamme try, SEM, XPS, XRD, etc. The electrochromic behaviour of the PPy/PB composi te system has been described in detail. Electrochromic display devices usin g solid polymer electrolytes, which are directly useful for commercial prod uction of such devices are currently under study. (C) 2000 Acta Metallurgic a Inc. Published by Elsevier Science Ltd. All rights reserved.