MnS nanocomposites based on doped graphene: simple synthesis by a wet chemical route and improved electrochemical properties as an electrode material for supercapacitors

Abstract

Nanocomposites of MnS anchored on graphene, nitrogen-doped graphene and boron-doped graphene have been prepared by a simple wet chemical process. The effect of graphene concentration in MnS and the effect of doping type in the composites are studied through the use of various characterization techniques. An electrochemical performance better than that of pure MnS has been observed in the graphene based composites. The doping of N and B atoms in graphene can further enhance the electrochemical activities of the nanocomposites. The present study demonstrates that MnS with doped graphene has large electrode/electrolyte interfaces, which offers more active sites and ensures a high charge storage capacity of the composite. A maximum specific capacitance of 696.6 and 353.8 F g⁻¹ are measured for MnS/BG-9 and MnS/NG-9 composite, respectively, at a 5 mV s⁻¹ scan rate, whereas the pure graphene composite (MnS/G-9) exhibits only a maximum specific capacitance of 156 F g⁻¹.