Composites Based on Polyaniline and Activated IR-Pyrolyzed Polyacrylonitrile As Promising Supercapacitor Electrode Materials

A method has been developed for synthesis of a composite coating based on polyaniline by introducing dispersed IR-pyrolyzed polyacrylonitrile, activated by alkaline treatment, into a polymer matrix. The coating is applied from a suspension in formic acid onto a graphite foil that has been previously subjected to anodic etching to improve the wettability with an electrolyte. The produced composite electrodes for sulfuric acid supercapacitors demonstrate high stability during long-term cycling. The specific electrochemical capacitance was 0.89 F cm–2, which is more than 2 times higher than that for an electrode with a polyaniline coating (0.41 F cm–2) tested under the same conditions. The main contribution to the increase in the total capacitance is made by the double-layer capacitance due to the rise in the active electrode surface.