One-Step Synthesis of Graphene Oxide/Polypyrrole/MnO2 Ternary Nanocomposites with an Improved Electrochemical Capacitance

The graphene oxide/polypyrrole/MnO2 (GO/PPy/MnO2) ternary nanocomposites have been synthesized via one-step in situ redox reaction. The reaction between KMnO4 and pyrrole monomers results in the simultaneous formation of PPy and MnO2 on the surface of GO nanosheets. The microstructures and properties of the GO/PPy/MnO2 ternary nanocomposite are characterized by X-ray diffraction (XRD), Raman spectroscopy, thermogravimetric analyses (TGA), scanning electron microscopy (SEM), energy dispersive X-ray diffraction (EDX), and electrochemical measurements. The results indicate that an improved specific capacitance of the GO/PPy/MnO2 ternary nanocomposite is obtained in 1.0 M Na2SO4 aqueous solution compared with that of GO/PPy binary nanocomposite. The ternary nanocomposite displays good rate capability and still retains 90% of the original specific capacitance after 1000 cycles by continuous cyclic voltammetric scans. The electrochemical results show that the ternary nanocomposite is a competitive candidate as an electrode material for future energy storage systems.