The Conducting polymeric materials have many physical properties which enable them to use invarious field like bioengineering, electronic, optical, chromic, electrical and medical engineering etc.Such one of promising candidate, polyaniline was synthesized via chemical oxidative polymerization process in acidic hydrochloric medic, taking potassium dichromate as an oxidant with doping of cobalt nitrate in different concentrations. The prepared doped polymeric composites were characterized by UV-visible spectroscopy, X-ray diffraction and dc conductivity measurement techniques. The UV-visible spectra of prepared composites revealed that the band gap decreases continuously with increases in dopant cobalt nitrate concentration and the peaks exhibiting the presence of charged particles. X-ray diffraction patterns of powdered composites showed amorphous nature as most conducting polymers exhibit. The DC conductivity of polymer composites has been measured in a specially designed measurement holder by two probe method in temperature range of 300-400 K and significant enhancement in dc conductivity has been observed with dopant and increase in temperature, proving the semiconductor nature of synthesized polymer composites.

Polyaniline, UV-Visible spectroscopy, X-ray diffraction, dc conductivity