Polypyrrole derivatives for electrochromic applications

Abstract

This review provides a comprehensive assessment of recent progress in polypyrrole derivatives which are specially designed for electrochromic applications.

A magenta polypyrrole derivatised with Methyl Red azo dye: synthesis and spectroelectrochemical characterisation

“…Whilst those with Eg less than 1.5 eV are cathodically-colouring materials, and coloured in the neutral state. Polymers with intermediate values for E g have distinct optical changes throughout the visible region and may exhibit several colours, such as PPy with Eg $ 2.7 eV [11,46,48]. The absorption spectra of the PMRPy film (Fig.…”

“…Usually, E g values of the conjugated polymers are in the range of 1.5-3.0 eV [2,11,46]. Polymers with E g greater than 3.0 eV are generally termed anodically-colouring because they are colourless in the neutral state, while absorbing (coloured) in the visible region in the oxidised state [47].…”

“…In spite of the large number of recent papers and reviews describing the synthesis, spectroelectrochemical properties and applications of PPy derivatives, there are, to our knowledge, only a few reports concerning the preparation and properties of magenta films of PPy derivatives and/or their copolymers [9,11,12,18].…”

“…Among p-conjugated polymers, polypyrrole (PPy) and its derivatives are particularly important due to their good electric conductivity and chemical stability in ambient atmosphere, besides their structural versatility, which allows tailoring of their electronic and electrochemical properties by the manipulation of the monomer structure [10][11][12]. The incorporation of azo-aromatic dyes, such as Methyl Red (2-[4-(dimethylamino)phenylazo]benzoic acid), into the polymer backbone would be quite interesting due to their reversible optoelectronic properties [9,[13][14][15][16].…”

Electrochromic Properties of Polyaniline-Based Hybrid Organic/Inorganic Materials

“…Currently, the development of new hybrid materials based on conjugated polymers have afforded materials with excellent characteristics for application in organic light emitting diodes (OLEDs), 1,2 organic field effect transistors (OFETs), 3 organic solar cells (OSCs), 4 and electrochromic devices (ECDs). [5][6][7] Electrochromic materials based on conjugated polymers show many interesting properties such as multicolor, fast switching speed, flexibility and easy to optimize their properties through molecular tailoring. 8,9 Among the organic polymeric electrochromic materials, polyaniline (PAni) has been widely studied due to many advantageous properties including high optical contrast (∆%T), environmental stability, easy synthesis, as well as comparatively low cost.…”