Ultrathin MnO2 nanosheets grown on hollow carbon spheres with enhanced capacitive performance

Abstract Ultrathin MnO2 nanosheets grown on the surface of hollow carbon spheres (MnO2/HCSs) were fabricated by the redox reaction between carbon spheres with KMnO4 in aqueous solution. Due to the porous structure and large amounts of active sites, MnO2/HCSs exhibit excellent capacitive performance with 227.5 F g−1 at 1 A g−1. After 5000 cycles, the capacity retention of MnO2/HCSs remains 96%, indicating its good cycling stability. These results demonstrate that MnO2/HCSs are promising supercapacitor electrode material and this work provide a facile method for growth of ultrathin MnO2 nanosheets on carbon substrate.