Effect of LiCl on conductivity of polyaniline synthesized via in-situ chemical oxidative method

An in-situ chemical oxidative method has been exploited for the synthesis of polyaniline (PANI) using HCl as a dopant, LiCl as a co-dopant and ammonium persulfate (APS) as an oxidizing agent at room temperature. The monomer to oxidant ratio has been optimized as 1:1.125 and the concentration of LiCl was varied from 0.0625 to 3 M. The synthesized polymer (PANI-LiCl) was characterized by Fourier transform infrared (FTIR) spectroscopy, Ultraviolet–Visible (UV–Vis) spectroscopy, X-ray diffraction (XRD) studies, Scanning Electron Microscopy (SEM) X-ray Photoelectron Spectroscopy (XPS) and Electrical conductivity measurements. The thermal properties of the synthesized PANI-LiCl have been characterized by Differential Scanning Colorimetry (DSC). The conductivity of the synthesized PANI-LiCl increases with the increasing concentration of LiCl from 0.0625 to 2.5 M. Further increase of LiCl concentration (3 M) drastically decreased the conductivity of PANI due to the saturation or over oxidation. The maximum electrical conductivity of 25.01 S cm−1 was realized for 2.5 M LiCl doped PANI.