Fabrication of polypyrrole/multi-walled carbon nanotubes composites as high performance electrodes for supercapacitors

The development of supercapacitor electrode material with high performance and low cost is a significant part of the research work. Herein, the polypyrrole (PPy)/Multi-walled carbon nanotubes (MWNTs) composites were synthesized by oxidative polymerization, when the iron (III) chloride (FeCl 3 ), methyl orange (MO), sodium dodecyl benzene sulfonate (SDBS) were used as the oxidant and dopant template. Various compounds of PPy and carbon nanotubes were synthesized, it shows a better capacity when the ratio of PPy and MWCNTs is up to 9:1.Under acidic conditions, the capacitance characteristics of the PPy/MWCNTs are better than other ones' when SDBS and MO are added, in other words, its ion exchange is more rapid and reversible. Electrochemical tests show that the initial discharge capacity of the PPy/MWCNTs composite electrode is 374.6 F/g. While the coulomb efficiency can remain 88% after 1000 discharge cycles, it indicates the good circulation stability of PPy/MWCNTs composite electrode material is obtained.