Facile deposition of polyaniline on the multi-walled carbon nanotubes/polyvinyl chloride composite films as flexible and robust electrodes for high performance supercapacitors

Highlights: • MWCNTs/PVC films were optimized as the conductive flexible substrate for PANI. • PANI/MWCNTs/PVC-2 electrode possessed high specific capacitance of 801 F g⁻¹ at 1 A/g. • It possessed a high tensile strength of 44.1 MPa with a breaking elongation of 1.6%. • More than 96% of specific capacitance was remained after 50 cycles of 180°-bending. Novel flexible and robust polyaniline/multi-walled carbon nanotubes/polyvinyl chloride (PANI/MWCNTs/PVC) composite films were designed as the free-standing electrodes for high performance supercapacitors, by deposition of polyaniline (PANI) via facile in-situ chemical oxidative polymerization of aniline on the multi-walled carbon nanotubes/polyvinyl chloride (MWCNTs/PVC) composite films, in which MWCNTs were introduced into the PVC matrix in order to improve its mechanical property and electrical conductivity. The MWCNTs/PVC composite film with MWCNTs content of 5% was optimized as the conductive flexible substrate, possessing a tensile strength of 44.1 MPa. The electrochemical tests showed that the PANI/MWCNTs/PVC-2 composite film electrode prepared by the rapid-mixing chemical oxidative polymerization exhibited better electrochemical performance than the PANI/MWCNTs/PVC₃-1 composite film electrode prepared by the conventional chemical oxidative polymerization, i.e. specific capacitance of 801.1 F g⁻¹ at a current density of 1 A g⁻¹, rate capacitance retaining 66.6% of its original value at high current density of 10 A g⁻¹ and 54.9% at scan rate of 100 mV s⁻¹, and long-term electrochemical cyclic stability with a retention of 90.6% after 2000 cycles of CV test at a scan rate of 100 mV s⁻¹. Furthermore, the PANI/PVC/MWCNTs-2 film electrode showed excellent tensile and tear-resistance performance and flexibility, indicating its promising application as bendable and robust electrode for energy storage devices.