Synthesis of polythiophene thin films by simple successive ionic layer adsorption and reaction (SILAR) method for supercapacitor application

In the present work, polythiophene thin films have been prepared by simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method at room temperature. The oxidative polymerization of thiophene monomer is carried out using FeCl3 as an oxidizing agent. The two beaker SILAR system was adopted with thiophene in acetonitrile solution as a cationic precursor and FeCl3 solution in double distilled water as an anionic precursor for polymerization of thiophene. The physico-chemical properties of polythiophene films are studied for the analysis of structural, morphological, optical and electrical properties. The XRD showed the formation of amorphous polythiophene, whereas electrical and optical studies showed p-type electrical conductivity and band gap 2.90 eV, respectively for polythiophene film. The electrochemical performance of polythiophene electrode was evaluated using cyclic voltammetry (CV) and galvanostatic charge–discharge measurements. A specific capacitance of 252 F g−1 was obtained in 0.1 M LiClO4 solution.

► Simple and inexpensive method used for the synthesis of polythiophene thin films.
► Supercapacitor with maximum specific capacitance of 252 F g−1.
► Polythiophene thin film electrode shows the stability up to 1000th cycles.