Hierarchical graphene oxide/polyaniline nanocomposites prepared by interfacial electrochemical polymerization for flexible solid-state supercapacitors

Hierarchical graphene oxide/polyaniline (GO/PANI) nanocomposites deposited on flexible substrates were synthesized by one-step interfacial electrochemical polymerization. PANI nanorods were coated on the surface of GO to form a three-dimensional nanostructure, which was prepared by the polymerization at the water/chloroform interface. The current density for interfacial electrochemical polymerization was up to 0.5 mA cm(-2), which is one-fold higher than that used in conventional electrochemical methods for nanostructures. Fourier transform infrared spectra, Raman and ultraviolet-visible absorption spectra indicated that PANI in a highly doped state showed a strong pi-pi electronic interaction with GO, resulting in an increased degree of conjugation. The flexible all-solid-state supercapacitors using GO/PANI nanocomposites exhibited a high specific capacitance of 1095 F g(-1) at 1 A g(-1), good rate capability and cycling performance, thus showing an energy density of 24.3 W h kg(-1) and the maximum power density of 28.1 kW kg(-1). This performance outperforms numerous previous solid-state supercapacitors that used carbon-based/PANI nanocomposites because of the synergistic effect of GO and PANI based on hierarchical nanostructures controlled by interfacial electrochemical polymerization.