Preparation Of Graphene Oxide/Polyaniline Nanocomposites For Flexible Solid-State Supercapacitors

Supercapacitor(SC) has been considered to be one of the ideal energy storage devices due to its high capability, a fast charge/discharge rate and a long working lifetime. Compared with traditional SCs using liquid electrolytes, flexible all-solid-state SCs have many advantages including bendability, portability, environmental friendliness and good stability. But the power and energy densities are still very low. Thus, exploring new electrode materials is critically important for flexible all-solid-state SCs.In this study, three-dimensional(3D) hierarchical graphene oxide/polyaniline(GO/PANI) nanocomposite was prepared by interfacial electrochemical polymerization. The biphasic electrolyte was applied for the deposition of GO/PANI nanocomposites on flexible substrates at a water/oil interface. The current density for interfacial electrochemical po lymerization was up to 0.5 mA/cm2, which was one- magnitude higher than that used in conventional electrochemical methods for nanostructures. PANI nanorods were coated on the surface of GO to form a 3D nanostructure. Fourier transform infrared spectra, Rama n spectra, ultraviolet- visible absorption spectra and X-ray photoelectron spectroscopy indicated that PANI was in a highly doped state and showed a mass fraction of 55.7 wt%. The slightly reduced GO showed a strong ?-? electronic interaction with PANI, favoring charge transfer at the interface. Flexible all-solid-state SCs based on GO/PANI nanocomposite showed a high specific capacitance of 1095 F/g at 1 A/g, good rate capability, cycling performance(1000 cycles, 91.1%) and bending stability(bending for 100 s, 95%), thus showing energy density of 24.3 Wh/kg and power density of 28.1 k W/kg. High performance arises from synergistic effect of GO and PANI and hierarchical nanostructures. The 3D hierarchical GO/PANI nanocomposite can be developed for advanced flexible all-solid-state SCs.