A novel hierarchical hollow nanostructure composed of δ-MnO 2 nanosheets deposited by in-situ growth on hollow carbon nanofibers (MnO 2 /HCNFs) was facilely synthesized using the hydrothermal method. Benefitting from its distinctive hollow structure, nanocomposite of MnO 2 /HCNFs exhibited an enhanced electrochemical property with higher specific capacitance (293.6 F g −1 at 0.5 A g −1 in 1 M Na 2 SO 4 electrolyte) compared to non-hollow structure. Further, an asymmetric supercapacitor (ASC) coin cell was assembled with the MnO 2 /HCNFs nanocomposites (positive electrode) and KOH-activated porous carbon nanofibers (PCNFs) (negative electrode). The asymmetric supercapacitor coin cell exhibited a maximum specific capacitance of 63.9 F g −1 at a high operating voltage window up to 2 V. Moreover, the ASC coin cell possessed a high energy density of 35.1 Wh kg −1 and showed a remarkable cycling stability and only 8.9% capacitance loss was found after 10,000 cycles, which implied the practicability for energy storage.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films