Polytoluidine blue-coated multiwalled carbon nanotubes: In-situ polymerization based hybrid nanostructure for high performance asymmetric supercapacitors

In this work, a series of multiwalled carbon nanotubes/polytoluidine blue (MWCNTs/PTB) with network structure are synthesized by in-situ oxidative polymerization. Electrochemical performance of MWCNTs/PTB are optimized through precise control of mass ratio between two components. Field emission scanning electron microscope analysis reveals a more homogeneous dispersion of network structure under the mass ratio of 1:3. Prepared MWCNTs/PTB-3 electrode exhibits the highest specific capacity of 232.7C g −1 and satisfactory specific capacity retention of 91.9 % after 5000 charge/discharge cycles in 1.0 M H 2 SO 4 electrolyte. Additionally, the assembled asymmetric supercapacitor exhibits energy density of 13.4 Wh kg −1 at power density of 600 W kg −1 and maintains exceptional cyclic stability. In conclusion, constructing carbon nanotube-supported conductive polymer composite proves to be an effective approach for enhancing the energy storage performance.