Electrochemical properties of graphene-MnO composite and hollow-structured MnO powders prepared by a simple one-pot spray pyrolysis process

Graphene-MnO composite and hollow-structured MnO powders are prepared by a simple one-pot spray pyrolysis process. The graphene content in the graphene-MnO composite powder is estimated to be 10 wt.%. The fine MnO crystals of size several tens of nanometers are uniformly distributed all over the graphene. The BET specific surface areas of the graphene-MnO composite and hollow-structured MnO powders are found to be 20 and 5 m² g^-1, respectively. The graphene-MnO composite powders have high initial discharge and charge capacities of 1207 and 849 mA h g^-1, respectively, at a current density of 500 mA g^-1. The initial discharge and charge capacities of the hollow-structured MnO powders are 1004 and 673 mA h g^-1, respectively. The discharge capacities of the graphene-MnO composite and hollow-structured MnO powders for the 130^th cycle are 1313 and 701 mA h g^-1, respectively.