Preparation of an amide group-connected graphene-polyaniline nanofiber hybrid and its application in supercapacitors

Polyaniline (PANI) nanofiber is grafted onto graphene to obtain a novel graphene-polyaniline (GP) hybrid. Graphene is activated using SOCl ₂ and reacts with PANI to form an amide group that intimately connects graphene and PANI. The existence of the amide group and its anchoring effect in the GP hybrid are confirmed and characterized by SEM, TEM, FT-IR, Raman, XPS and quantum chemistry analyses. Electrochemical tests reveal that the GP hybrid has high capacitance performances of 579.8 and 361.9 F g ^-1 at current densities of 0.3 and 1 A g ^-1. These values indicate superiority to materials interacted by van der Waals force. Long-term charge/discharge tests at high current densities show that the GP hybrid preserves 96% of its initial capacitance, demonstrating good electrochemical stability. The improved electrochemical performance suggests promising application of the GP hybrid in high-performance supercapacitors.