Characterization of Electrochromic Properties of Polyaniline Thin Films Electropolymerized in H<sub>2</sub>SO<sub>4</sub> Solution

Abstract

Polyaniline (PANI) onto indium-doped tin-oxide (ITO)-coated glass samples were prepared by electroopolymerization in 0.5 M H 2 SO 4 solution. Structure and morphology characterization of the PANI films demonstrated that the films were grown onto ITO substrates in the form of polycrystalline microbelts separated by micropores. By analysing the UV-Vis absorption spectra of the PANI films, the energy bandgap was found to be approximately 2.75 eV. The PANI/ITO films exhibited a good reversible electrochromic display (ECD) performance when cycled in 0.1 M LiClO 4 + pro-pylene carbonate. The response time of the ECD coloration was found to be as small as 15 s and the coloration efficiency was found to be 8.85 cm 2 × C −1 . After 100 cycles of the ECD performance, the cyclic voltammetry curve of the working electrode maintained unchanged. This demonstrates that the electropolymerized PANI films can be served as a good candidate for ECD applications, taking advantage of their excellent properties in terms of chemical stability.

Electrochromic Properties of PANI/TiO2 Nanocomposite Films Prepared by Electropolymerization

“…Then PANI/nc-TiO2/ITO films were deposited by electropolymerization method using a solution of the pure reagent grade aniline and sulphuric acid (H2SO4) as reported in [8]. The electrochemical processes were carried-out by using a Potentiostat PGS-30 in a standard three-electrode cell, where nc-TiO2/ITO served as working electrode (WE), Ag/AgCl as reference electrode (AAE) and a platinum grid as counter electrode (CE).…”

“…The PANI-copolymer/ITO electrode has electrochromic display of the inverse change of green-to-blue light. We also prepared PANI/ ITO by using electropolymerization of aniline in a dilute H2SO4 solution [8]. As-prepared PANI films have a bell-like nanoporous structure.…”

Physico-chemical factors conditioning the electronic conduction of conductive polymers

“…By a redox process the electrical conductivity of the PANI allows to pass from one form to another, the degree of its protonation is a crucial factor for the conductivity of the emeraldine form of polyaniline. (The electrical conductivity increases by ten orders of size when its protonation increases by 20%) [11].…”

Optical, Structural and Electrical Properties of Electrochemical Synthesis of Thin Film of Polyaniline

“…It symbolizes a group of macromolecules which conductivity of electrical enables changes from an insulator for a conductor through the redox procedure. The electron conductivity of polyaniline in the formula of emeraldine depends on its protonation and growths by ten orders of magnitude as the degree of protonation is increased from 0 to 20% (2). Indeed, the summary of heteroatoms makes it possible to compensate for the lack of stability of the Polyacetylene in the presence of atmospheric conditions.…”

“…Organic photovoltaic cells (7), gas sensors (8,9,10), a solid electrolytic capacitor (11), electrochromic windows and displays, and packaging, polymeric batteries (12,13). 1,2 Department of Physics, College of Science for Women, University of Baghdad, Baghdad, Iraq * Corresponding :salahabd55@yahoo.com in addition to electric chromic projectors (14). History from conjugated polymers began in the early 1970s when the sulfur polynitride [(-S = N-) x] at room temperature has conductivity close to that of metals.…”