Covalently bonded polyaniline/fullerene hybrids with coral-like morphology for high-performance supercapacitor

In this article, we report a novel fullerene–polyaniline emeraldine base (C60–PANI-EB) hybrid synthesized through covalent bonding of polyaniline (PANI) onto para-phenylenediamine (PPD)-functionalized fullerene and its capacity properties. C60–PANI-EB exhibits a unique coral-like porous morphology with PANI particles interconnected by nanofibers. In comparison with polyaniline emeraldine base (PANI-EB), C60–PANI-EB shows significantly higher specific capacitance, specific power and specific energy, and better cycling stability. The specific capacitance of C60–PANI-EB and PANI-EB are 776 F g−1 and 492 F g−1 at current density of 1 mA cm−2, respectively. The specific capacitance of C60–PANI-EB has 37% enhancement over that of PANI-EB even at high current density of 100 mA cm−2. The specific energy of C60–PANI-EB is 64 Wh kg−1 at 1 mA cm−2 and the specific power is 36,595 W kg−1 at current density of 100 mA cm−2. The greatly enhanced capacity performance can be attributed to the increased ionic conductivity induced by the loose molecular packing structure and porous morphology as well as the increased electrical conductivity caused by the coral-like interconnected morphology and the strong electron-withdrawing function of the fullerene through its covalent bonding to PANI.