Electrical Properties of Impurity Doped Ion Conducting Polymers

Abstract

Generally polymers have been considered to be insulators, but they can now be “tailored” as conducting polymers and can be synthesized for applications, especially for the semiconductor and electronic industries. Polymers can be made to conduct either electronically or ionically. Polymer materials that conduct ions can be described as ion conducting polymer electrolytes. While as prepared polyethylene oxide (PEO) samples are insulators with very low conductivity (10^-10 Scm^-1), impurity ion doped PEO showed conductivity values in the range of 10 Scm^-5 Scm^-1. The conductivity of electron conducting polymers can reach values as high as 10⁵ Scm^-1. Doping of polymers such as PEO can change its electrical properties significantly and infact make it a semiconducting material.¹ This property has opened up new areas of applications such as solid state batteries, electrochromic windows and fuel cells.

PEO doped with various divalent cations from first transition metal group have been investigated. These materials are prepared as thin films from solution casting technique and are further characterized for their suitable applications. Structural studies are carried out spectroscopically and electrical properties are determined by ac and dc conductivity measurements. Other techniques such as DTA and XRD have been used to get a better understanding of these materials.