Remarkable Stability of Supercapacitor Material Synthesized by Manganese Oxide Filled in Multiwalled Carbon Nanotubes

Improving the electrochemical stability of manganese oxide/multiwalled carbon nanotubes (MnO2/MWCNTs) nanocomposites is of great importance to many electrochemical supercapacitor applications. In this study, the electrochemical properties of MnO2 filled inside the cavity of MWCNTs were investigated for the first time. The prepared nanocomposite was characterized by means of X-ray photoelectron spectroscopy (XPS), X-ray diffraction patterns (XRD), transmission electron microscopy (TEM) images, scanning electron microscopy (SEM) together with energy dispersive X-ray spectroscopy (EDX) and thermogravimetric analyses (TGA). Electrochemical characterization has been performed using cyclic voltammetry (CV), galvanostatic charging/discharging (CD) test. The TEM image, XRD analysis confirmed the high structural stability and CD test complied the high electrochemical stability of the prepared nanocomposite. Besides, MnO2/MWCNTs nanocomposite supercapacitor showed superior cycling stability in the potential range of 0 1.0V due to the filling of the electroactive material inside the tubes and retained 96% of initial capacitance even over 200 cycles.