ELECTROCHEMICAL BEHAVIOR OF POLYANILINE (PANI) DOPED WITH DIFFERENT NITRATE SALTS
Polyaniline (PANi) was synthesized from double distilled aniline dissolved in HNO3 solution by chemical oxidative polymerization method using ammonium persulfate (APS) as an oxidant at room temperature. Five PANi samples were prepared by doping with different metal nitrate salts like KNO3, Ni (NO3)2.6H2O, Pb(NO3)2 and La(NO3)3.6H2O at room temperature. Among the five PANi samples, a maximum conductivity of 8.7765´10-2 S cm-1 was found in PANi-La and a minimum of 1.8804´10-2 S cm-1 in PANi-H. The CV curve shows that sample PANi-K has the highest specific capacitance value of 150.25 F g-1 in comparison to other samples and also the charge discharge cycle shows the highest specific capacitance value of 186.65 F g-1 for the sample PANi-K. FTIR spectrograph confirms the presence of functional groups and also the interaction between the polymer chains with dopants. Furthermore, the observed spectral features also reflect physical ordering and aligned conformation of the PANi, which is in correlation with the XRD. The XRD pattern indicates that PANi samples have systematic arrangement of the polymer chain with a semi crystalline nature. Based on the electrochemical properties
found, PANi-K would be the best material for supercapacitor application in comparison to other samples.