Synthesis and electrochemical capacitance performance of polyaniline doped with lignosulfonate

Polyaniline doped with lignosulfonate (PANI/LGS) was prepared by using a facile oxidative polymerization of aniline with (NH4)2S2O8 as an oxidant, and the structure and morphology of PANI/LGS were investigated. As an active material for supercapacitors, the capacity retention rate of PANI/LGS was 75.1% with a growth of current density from 0.2 to 10 A g−1, indicating a high rate performance, and that of PANI was only 38.3%. For PANI/LGS, a specific capacitance of 377.2 F g−1 remained at 10 A g−1, and that of PANI was 183.7 F g−1. Moreover, the cycling stability was also measured in a two-electrode symmetrical capacitor at a current density of 1.0 A g−1. The capacity retention rate of PANI/LGS was 74.3% after 10 000 cycles, and that of PANI was 52.8%.