Ethylene glycol reduced graphene oxide/polypyrrole composite for supercapacitor

Highlights: ► A novel EG-RGO/PPy composite for supercapacitor application is well constructed. ► The well-soluble GO was dispersed in aqueous polymerisable aniline monomer solution to form stable GO/PPy structure. ► The EG reduced RGO/PPy can retain the PPy conductive conjugative frameworks. ► The EG-RGO/PPy electrode exhibits superior electrochemical capability as supercapacitor electrode. -- Abstract: A promising supercapacitor material based on graphene/polypyrrole (PPy) has been successfully synthesized via in situ oxidation polymerization of pyrrole monomers in aqueous graphene oxide (GO) solutions, followed by chemical reduction using ethylene glycol (EG). Unlike the commonly employed hydrazine reduction, the moderate EG reductant does not destruct the PPy conjugative structures, thus facilitating utilization of the electroactive conductive polymer. The morphologies and the structures of the as-prepared materials are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra, and Fourier transform infrared spectroscopy (FTIR). And the electrochemical performance of the fabricated electrodes was evaluated by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The EG-RGO/PPy electrode shows large specific capacitance, high rate performance, and good charge–discharge stability as well. The excellent electrochemical capability is mainly accounted for the sound composite construction that improves the effective utilization of electroactive PPy component, accelerates shuttling the charged carriers, and alleviates the swelling/shrinkage of polymer chains