Reduced graphene oxide-mediated synthesis of Mn 3 O 4 nanomaterials for an asymmetric supercapacitor cell.

Herein, Mn 3 O 4 /reduced graphene oxide composites are prepared via a facile solution-phase method for supercapacitor application. Transmission electron microscopy results reveal the uniform distribution of Mn 3 O 4 nanoparticles on graphene layers. The morphology of the Mn 3 O 4 nanomaterial is changed by introducing the reduced graphene oxide during the preparation process. An asymmetric supercapacitor cell based on the Mn 3 O 4 /reduced graphene oxide composite with the weight ratio of 1 : 1 exhibits relatively superior charge storage properties with higher specific capacitance and larger energy density compared with those of pure reduced graphene oxide or Mn 3 O 4 . More importantly, the long-term stability of the composite with more than 90.3% capacitance retention after 10 000 cycles can ensure that the product is widely applied in energy storage devices.