Effect of poly(3,4-ethylenedioxythiophene) (PEDOT) on the pseudocapacitive properties of manganese oxide (MnO2) in the PEDOT/MnO2/multiwall carbon nanotube (MWNT) composite

•Effect of PEDOT on electrochemical properties of MnO2 in PEDOT/MnO2/MWNT composites is studied.•PEDOT was coated onto MnO2/MWNT composites without affecting the morphology of MnO2.•PEDOT functions as an electrically conductive layer in PEDOT/MnO2/MWNT composites.•PEDOT improves the rate capability rather than the specific capacitance of MnO2. The effect of the presence of poly(3,4-ethylenedioxythiophene) (PEDOT) on the pseudocapacitive properties of manganese oxide (MnO2) is investigated using PEDOT/MnO2/multiwall carbon nanotube-based (MWNT) coaxial composites containing different PEDOT contents. To prepare these PEDOT/MnO2/MWNT coaxial composites, a nanometer-thick outer layer of PEDOT was electrochemically polymerized onto the MnO2/MWNT composite, without affecting the morphology of MnO2. The pseudocapacitive properties of the MnO2/MWNT and PEDOT/MnO2/MWNT composites were evaluated by cyclic voltammetry. By analysis of the voltammetric charge, the outermost PEDOT layer on the MnO2/MWNT composite was found to improve the rate capability mainly through acting as an electrically conductive layer, rather the specific capacitance of the MnO2/MWNT composite.