Preparation and electrochemical capacitive performance of polyaniline nanofiber-graphene oxide hybrids by oil–water interfacial polymerization

Polyaniline nanofiber-graphene oxide (PANIF-GO) hybrids were fabricated by oil–water interfacial polymerization. The structures of PANIF-GO hybrids, pure PANIF and GO were examined by high resolution transmission electron microscopy. It was found that PANIFs were homogeneously inserted between the GO layers or absorbed on the surface of the GO. Fourier transform infrared spectroscopy and X-ray diffraction showed that PANIFs effectively increased the interlayer distance of GO from 0.83 nm to 1.38 nm. Electrochemical properties for the hybrid electrode were tested by cyclic voltammetry and electrochemical impedance spectroscopy using a three-electrode system. The results indicated that a high specific capacitance of 564.7 F g−1 for the hybrids was measured at the current density of 0.5 A g−1 in a 1 M H2SO4 aqueous solution compared to 352.8 F g−1 for pure PANIF and 30.1 F g−1 for GO. Moreover, the PANIF-GO hybrids showed a very long cycle life with only 9.4% specific capacitance loss after 2000 cycles. The as-prepared hybrids are remarkable electrode materials for the supercapacitors.