Effect of multi-walled carbon nanotubes and conducting polymer on capacitance of mesoporous carbon electrode

Porous carbon is the most widely used electrode materials in energy storage devices. It is generally accepted that in such electrodes, mesoporosity is more desired in supercapacitor than microporosity for the ions tranportation. However, the relatively poor conductivity of porous carbon often leads to low capacitance. To improve the capacity of mesoporous carbon based electrode, we designed a composite film composed of mesoporous carbon, multiwalled carbon nanotubes (MWNTs) and conducting polymer, Poly-3,4-ethylenedioxythiophene/poly(styrenesulfonate) (PEDOT-PSS), and hoped that each component in the composed film could contribute synergetically to improve electrochemical properties. The electrochemical performance of the film was evaluated by cyclic voltammetry and constant current charge/discharge method. With the assistance of MWNTs and conducting polymer, the specific capacitance of the mesoporous carbon based electrode was amplified six times. The electrode also presented excellent charge/discharge rate and good cycling stability, retaining about 94% of its initial capacitance after 1000 cycles. The results demonstrated that mesoporous carbon is more effectively utilized with assistance of MWNTs and conducting polymer in the electrode. Such method is very promising for the future applications of the porous carbon in electrode materials for high performance electrochemical supercapacitors.