Transition Metal-Doped Polyaniline/Single-Walled Carbon Nanotubes Nanocomposites: Efficient Electrode Material for High Performance Supercapacitors

The demand for superior energy storage devices, such as supercapacitors, has been growing to meet the application requirements of hybrid vehicles and renewable energy systems. Here, we report a simple method to synthesize manganese chloride (MnCl2)-doped polyaniline (PANI)/single-walled carbon nanotubes (SWCNTs) nanocomposites for electrochemical supercapacitors. The possible interactions between MnCl2 and both PANI and SWCNTs was studied by Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy, and Raman spectroscopy. The morphological characteristics of the electrode materials were investigated by field emission scanning microscopy (FESEM) and transmission electron microscopy (TEM). As-prepared nanocomposites showed higher electrical conductivity of 9.65 S/cm at room temperature and reached nonlinear current-voltage characteristics. A maximum specific capacitance of 546 F/g has been obtained for the nanocomposites at 0.5 A/g current density. Transition metal doping and SWCNTs enhance the electrochemical properties of the nanocomposites. The better specific capacitance and charge/discharge rates make them promising candidates as electrodes in supercapacitors, combining high energy densities with high levels of power delivery.