Assembling fabrication and capacitance of manganese oxide nanosheets and functionalized carbon nanotubes hybrid material

The manganese oxide nanosheets (MnO2) with negative charge and the functionalized carbon nanotubes (CNTs) with positive charge are selected as assembling blocks, and the manganese oxide nanosheets and functionalized carbon nanotubes hybrid material (CNTs–MnO2 hybrid material) is fabricated by an assembling flocculation method. The restacking process of the manganese oxide nanosheets is effectively prevented due to the existence of CNTs, and manganese oxide nanosheets exist in nearly exfoliation state in CNTs–MnO2 hybrid material. The morphology and structure of the obtained materials are investigated by FTIR, XRD, SEM and TEM. A unique flaky appearance is observed for hybrid material. The capacitance of the CNTs–MnO2 hybrid material is investigated by cyclic voltammetry (CV) and Nyquist plots. A strong synergistic effect between the functionalized CNTs and exfoliated MnO2 is observed. The doped CNTs not only increase the utilization of manganese oxide nanosheets in the active cathode material, but also improve its performance at the high rate charge and discharge. The capacitance of CNTs–MnO2 hybrid material electrode is about 285 F g−1 at 5 mV s−1. A relative high specific capacitance of 151 F g−1 can be maintained even at 100 mV s−1.