Investigation of Structure and Electrical Conductivity in Doped Polyaniline

✍ Scribed by Chaudhari, H. K.; Kelkar, D. S.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 273 KB
• Volume: 42
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(199704)42:4<380::aid-pi727>3.0.co;2-f

✦ Synopsis

Polyaniline (PAn) was synthesized chemically and doped with various dopants, such as HCl, HCOOH, and methylene blue S), by an I 2 (C 16 H 18 ClN 3 immersion method. The structure of these samples was investigated by infrared (IR) spectroscopy and wide-angle X-ray di †raction (WAXD) analysis. Remarkable changes have been observed in the IR spectra of doped PAn, indicating that doping is a †ecting the chemical structure. The percentage crystallinity was also found to increase after doping. The electrical conductivity (p) of these samples was measured at various temperatures (T \ 308 K to 423 K). Plots of log p versus Ty, where y \ [1/2, [1/3, [1/4, were obtained and used to identity the conduction mechanism. Undoped PAn shows semiconducting behaviour, while doped samples show a variable range hopping mechanism. A primary cell was constructed with HCl-doped PAn as one of the electrodes and a copper plate as the other electrode. It gave an open circuit voltage of 0É38 V and a short circuit current of about 5É4 mA.