Development of nanohybrids based on carbon nanotubes/P(EDOT-co-MPy) and P(EDOT-co-PyMP) copolymers as electrode materials for aqueous supercapacitors

We present the synthesis of nanohybrids based on carbon nanotube with EDOT/Py derivatives copolymers, P(EDOT-co-MPy) and P(EDOT-co-PyMP). These hybrids were prepared with functionalized MWCNT via in-situ polymerization for aqueous supercapacitor applications. The chemical structure and morphology of the hybrids were compared with those of neat copolymers and MWCNTs using FTIR, Raman and XPS spectroscopies. The results provided evidence of a covalent attachment between the copolymer and nanotubes. The electrodes were used in symmetric supercapacitor cell configuration and their performance was evaluated using cyclic voltammetry (CV), galvanostatic charge/discharge tests and electrochemical impedance spectroscopy (EIS). The hybrids presented an improvement in the capacitance values compared to a pure capacitive system (MWCNT) and the neat copolymers. The rate capability of the cells was also improved as a result of an enhancement in charge transfer in the nanohybrids. The devices showed high performance with excellent cycling stability, compared to the poor cyclability of the conjugated polymers, even after 20,000 cycles.