Three-dimensional hybrid materials of fish scale-like polyaniline nanosheet arrays on graphene oxide and carbon nanotube for high-performance ultracapacitors

Three-dimensional (3D) hybrid materials composed of 2D fish scale-like polyaniline (PANI) nanosheet arrays on graphene oxide sheets and carbon nanotubes were synthesized by a one-step process using a simplified template-free polymerization method. PANI nanosheet growth is proposed to be accomplished through electrostatic interaction, hydrogen bonding, and π–π stacking interaction. Such a material exhibits specific capacitances of 589 and 413 F g−1 at 0.2 and 5 A g−1, respectively, compared to pristine PANI of 397 and 180 F g−1. After 1000 cycles, the composite still retains 81% of its initial capacitance, while PANI retains only 48%.