A novel nitroxide radical polymer-containing conductive polyaniline as molecular skeleton: its synthesis and electrochemical properties as organic cathode

A novel nitroxide radical-containing aniline, 4-(6-(2-amino-phenol-9 H -yl)hexanoyloxy)-2,2,6,6-tetramethylpiperidin-1-yloxy (AnT), was synthesized, and the copolymers of AnT and aniline (P (An-co-AnT)) were then prepared by chemical oxidative polymerization. The introduction of polyaniline (PAn) skeleton in copolymers improved the charge migration along polymer backbone, and the increased ratio of An/AnT monomer makes PAn’s anodic peak in copolymers shift to negative potential and the redox peaks for the nitroxide radical shift to the positive potential. Also, P (An-co-AnT) exhibited a gradually increased charged specific capacity from 120.1 to 141.0 mAh g −1 with increasing the feeding ratio of AnT/An, while the discharge specific capacity presented an opposite result. Specially, P (An-co-AnT) exhibited an obvious charge voltage platform and an even improved cycling stability than that of PAn in the high feeding ratio of AnT/An, and after 20 cycles, the discharge capacity of P (An-co-AnT) (1:1 ([An]/[AnT])) still maintained 82.7 % of the capacity obtained at the initial cycle.