Enhancement of Discharge Capacity of Mg/MnO2 Primary Cell with Nano-MnO2-Graphene as Cathode

In the present study, pristine a-MnO 2 and graphene mixed with nanoparticles a-MnO 2 -based cathode were prepared and their electrochemical performances were studied in a magnesium/ manganese dioxide-graphene (Mg/a-MnO 2 - graphene) primary battery cell. A modified Mg/MnO 2 -graphene primary cell was constructed using the prepared α-MnO 2 nanoparticles [Sample A (α-MnO 2 ) and Sample B (α-MnO 2 -graphene)] and electrochemically synthesized graphene in a Swagelok type cell. The discharge measurements of the modified Mg/MnO 2 cell were analyzed using galvanostatic constant current (1, 5 and 10 mA) discharge with the cutoff voltage of 0.2V. The discharge capacity of α-MnO 2 based cathode was 20, 46 and 73 mAhg -1 respectively at 1, 5, 10 mA constant current, respectively. Similarly the discharge capacity of α-MnO 2 -graphene based cathode was 68, 308 and 271 mAhg -1 , respectively. Moreover, the discharge capacity of cathode based on α-MnO 2 -graphene increased three times compared to α-MnO 2 based electrode. The present work unveils that graphene-a-MnO 2 based cathode is suitable for primary magnesium battery application.