MWNTs/PANI composite materials prepared by in-situ chemical oxidative polymerization for supercapacitor electrode

Multi-walled carbon nanotubes (MWNTs)/ polyaniline (PANI) composite materials were prepared by in-situ chemical oxidative polymerization of an aniline solution containing well-dispersed MWNTs. The supercapacitive behaviors of these composite materials were investigated with cyclic voltammetry (CV), charge–discharge tests, and ac impedance spectroscopy, respectively. The composites based on the charge-transfer complex between well-dispersed MWNTs and PANI matrixes show much higher specific capacitance, better thermal stability, lower resistance, and were more promising for applications in supercapacitors than a pure PANI electrode. The highest specific capacitance value of 224 Fg-1 was obtained for the MWNTs/PANI composite materials containing MWNTs of 0.8 wt%. The improvement mechanisms of the capacitance of the composite materials were also discussed in detail.