Preparation of porous nanorod polyaniline film and its high electrochemical capacitance performance

Nano-sized polyaniline (PANI) films were electrochemically deposited onto an ITO substrate by a pulse galvanostatic method (PGM) in an aqueous solution. The morphology of the as-prepared PANI film was characterized using a field emission scanning electron microscope (FESEM). It was observed that the as-prepared PANI films were highly porous, and showed a nano-sized rod-like or coralline-like morphology depending on the charge loading performed in the electropolymerization process. Furthermore, the PANI films were electrochemically measured by the galvanostatic charge-discharge (GCD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests in 1 mol L^-1 HClO₄ solution. The results showed that such PANI films had a favorable electrochemical activity and an excellent capacitance. The rod-like PANI film prepared with the charge loading of 1000 mC showed the highest discharge capacitance of 569.1 F g^-1 at a low current density of 1 A g^-1. The discharge capacitance retained 97.7% after 1000 cycles at a large current density of 10 A g^-1.