Synthesis of nitrogen doped coiled double walled carbon nanotubes by chemical vapor deposition method for supercapacitor applications

Recently carbon nanostructured materials are more attractive for the supercapacitor applications. Pure carbon nanotubes (CNTs) and double walled nitrogen doped carbon nanotubes (N-DWCNTs) have been synthesized for electrode material for the Supercapacitor applications. The N-DWCNTs were synthesized by Thermal Chemical Vapor Depositions (T-CVD) and they are coil shaped. The synthesized N-DWCNTs were characterized by powder X-ray diffraction (XRD) technique. The morphology of coil shaped N-DWCNTs were revealed by the Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The Electrochemical performance of pure CNTs and N-DWCNTs was analyzed using Cyclic Voltammetry (CV) with 0.5 M H2SO4 electrolyte. It showed the good pseudocapacitance behavior for N-DWCNTs. Electrochemical impedance spectroscopy (EIS) was measured for N-DWCNTs and showed the smaller charge transfer resistance (Rct – 7.731 Ω) which is much smaller than that of CNTs (23.69 Ω). The specific capacitance was measured for pure CNTs (23.40 F/g) and N-DWCNTs (51.29 F/g) with current density 0.125 A/g. [Display omitted] •Carbon nanotubes synthesis forest like growth on metal foils.•The coil/helical shaped Nitrogen doped double walled carbon nanotubes.•Thermal CVD for different carbon nanotubes growth on metal foils.•The helical shaped carbon nanotubes for supercapacitor applications.