Effect of Graphene Oxide as a Dopant on the Electrochemical Performance of Graphene Oxide/Polyaniline Composite

A method for preparing a graphene oxide/polyaniline (GO/PANI) composite electrode was developed to investigate the effect of GO doped in PANI. PANI was first prepared by the polymerisation of aniline and then dedoped by NH4OH to form emeraldine base (EB). The dedoped PANI and as-prepared GO were dissolved in N-methyl-2-pyrrolidone (NMP) to generate a homogeneous dispersion. The GO/PANI composites were redoped in HCl before use as electrode materials. These composites were characterised by Raman spectroscopy, X-ray diffraction, UV-vis adsorption spectroscopy, scanning electron microscopy, atomic force microscopy and electrochemical measurements. The GO/PANI composite electrode (containing 2.5% GO) has an initial gravimetric capacitance of 896 F g−1 at a scan rate of 5 mV s−1 and a retention life of 51% after 500 cycles, which is an improvement over that of pure PANI (23%). The results show that the synergy of GO and PANI attributes to the good electrochemical performance of the GO/PANI composite electrode.