Performance Of Conductive Polymers Coaxial Nanotubes-based Supercapacitor Electrode

Supercapacitor,a new type of electrochemical energy storage device,has advantages of a high power density,fast charge/discharge rate and environment-friendly properties.So it has been widely used in the field of power energy.However,the existing supercapacitor system with carbon material as electrode has some disadvantages,such as poor capacitance and energy density.The conducting polymer materials have turned into promising supercapacitor electrode materials with higher theoretical capacity and mature preparation method.However,electrochemical stability of conducting polymer occurs decay during long-term cycling,which has become the biggest obstacle to further application.In this paper,we used self-degraded template method to prepare tubular polypyrrole by controlling the concentration of raw materials,and then developed polypyrrole/polyaniline coaxial nanotubes?PPy/PANI CANTs?hybrid by electrodeposition of PANI.Electrochemical tests revealed specific capacitance of 390F g^-1 after 2000 cycles at a current density of 2 A g^-1,which demonstrates that PANI coating plays an important role in improving the electrochemical performance of PPy electrode materials.On this basis,PPy/PANI CANTs were embedded in graphene to form 3DGP composite foam and electrochemical tests show that 3DGP electrode delivers specific capacitance of 463 F g^-1 at a current density of 2 A g^-1 after 2000 cycles.3DGP foam integrated the advantages of conducting polymer,graphene coating,tubular structure and three dimensional structure,which could greatly alleviate the capacitance loss problem of the conducting polymer electrode material during cycling.PPy/PANI CANTs-graphene could be further combined with the direct ink writing technology and applied to wearable electronics.