Abstract
Polyaniline (PANI) synthesized by a potentiostatic method at 4 °C in 1 M HNO 3 with the polymerization charge density equal to/less than 0.45 C cm -2 was demonstrated to exhibit ideally capacitive characteristics (i.e. high reversibility and high-power property) with a high specific capacitance of 210 F g -1 for the application of electrochemical supercapacitors in NaNO 3 . Influences of the polymerization charge density (i.e. the polymer loading) and the polymerization temperature on the capacitive characteristics of PANI films compared by both cyclic voltammetry and charge-discharge technique were reasonably correlated with their structural properties examined by X-ray photoelectron spectroscopy (XPS). The highest specific capacitance of a PANI film polymerized at 4 °C was attributed to its lowest density of structure defects. The surface morphology of these PANI films was examined by a scanning electron microscope (SEM). © 2002 Elsevier Science Ltd. All rights reserved.