Chemistry of Materials · 2002 · 588 citations · 43 references
Natural SciencesMaterials EngineeringMaterials ScienceElectrochemical EngineeringElectrochemistryNanomaterialsCarbon NanotubesConducting PolymersElectrochemical Impedance SpectroscopyElectrode MaterialsNanotubesSupercapacitorsCapacitanceComposite Electrode MaterialsConducting Polymer CompositesElectrochemical Impedance AnalysisMulti-walled Carbon NanotubesNanocomposite FilmsPolypyrroleVoltammetry
This work reports the supercapacitive properties of electrochemically grown composite films of multiwalled carbon nanotubes (MWNT) and polypyrrole (PPy), a conducting polymer. Scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy revealed that the nanoporous three-dimensional arrangement of PPy-coated MWNTs in these films facilitated improved electron and ion transfer relative to pure PPy films. The low-frequency capacitance was measured for films of varying thickness, revealing specific capacitances per mass ( C mass ) and geometric area ( C area ) as high as 192 F g - 1 and 1.0 F cm - 2, respectively. Rates of charge and discharge about an order of magnitude faster than similarly prepared pure PPy films were also observed.
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