The polyaniline coated multi-walled carbon nanotubes (PANI/CNTs) composites were synthesized by in situ polymerization. The microstructure and component of the composites were characterized by scanning electron microscope (SEM), Fourier transfer infrared spectroscopy (FTIR), X-ray diffraction (XRD), and N2 adsorption BET. The electrochemical performances of the samples were tested by cyclic voltammogram (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge. The results showed that the thickness of PANI layer on the surface of CNTs was ca. 50 nm. The specific capacitance of the ob- tained composite material was about 305.3 F g-1, which was much better than the specific capacitance of the pure CNTs (31 F g-1).
