Enhanced electrochemical behavior and hydrophobicity of crystalline polyaniline@graphene nanocomposite synthesized at elevated temperature

This paper reports a simple route for the synthesis of graphene (GN) using an electrochemical method as well as its composite with polyaniline (Pani). The resulting nanocomposite contained high crystalline regions due to the in-situ oxidative polymerization performed at elevated temperatures. Thus prepared GN, Pani and Pani@GN nanocomposite were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). Morphological studies showed that Pani formed a smooth coating over the surface of GN. A shift in the FTIR, Raman and XPS spectra of the Pani@GN nanocomposite also supports the strong interactions between Pani and GN, confirming the successful synthesis of the Pani@GN nanocomposite. XRD and selected area electron diffraction revealed the highly crystalline nature of Pani in the Pani@GN nanocomposite, highlighting the efficacy of the preparation method. The Pani@GN nanocomposite showed higher DC electrical conductivity and capacitance than Pani. The enhanced performance of the Pani@GN nanocomposite was attributed to the large surface area provided by GN, facilitating the rapid transport of electrolyte ions into the electrode during the redox process. The Pani@GN nanocomposite also exhibited better hydrophobicity due to the incorporation of GN.