Facile PVP-Assisted Synthesis of MnO2@MWNT Composites and their Application in Supercapacitors

A composite of well dispersed MnO 2 nanoparticles adhered on multi-walled carbon nanotubes (MnO 2 @MWNT) is obtained through facile hydrothermal process and followed by high temperature annealing. The nanoscale MnO 2 particles were homogeneously distributed on the surface of MWNTs under polyvinyl pyrrolidone (PVP)-assisted reaction. The MnO 2 @MWNT composite (34.43 wt. % MnO 2 ) displays a high specific capacitance of 285.12 F/g at a current density of 1 A/g in 1 M Na 2 SO 4 electrolyte. The electrode exhibits good cycling stability, which the specific capacitance retention retains up to 90.17% after 1000 cycles at 1 A/g.