MnO2/polypyrrole nanotubular composites: reactive template synthesis, characterization and application as superior electrode materials for high-performance supercapacitors

A novel MnO2/polypyrrole (PPy) heterogeneous composite with nanotubular structure is reported by a facile preparation of in situ chemical polymerization via a reactive template of MnO2. MnO2 nanotubes are found to be served as both appropriate oxidants and scaffolds to polymerize conducting PPy nanocoatings on the surface, thus constructing a unique coaxial configuration. The electrochemical measurements show that both components in the hybrid nanocomposites exhibit highly pseudocapacitive behavior in neutral KCl aqueous electrolyte. MnO2/PPy nanocomposites prepared from an initial MnO2/pyrrole ratio (3:1) deliver a maximum specific capacitance of 337 F g−1 at 0.5 A g−1 with good rate capability and long-term cycling stability, demonstrating their promising applications in high-performance supercapacitors. Moreover, the synthetic methodology may provide a generic guideline in developing different nanostructured MnO2/PPy electrode materials for electrochemical energy storage.