Hydrothermal synthesis of high specific capacitance electrode material using porous bagasse biomass carbon hosting MnO2 nanospheres

In this article, a high specific capacitance biomass carbon/MnO2 nanocomposites electrode materials were prepared by hydrothermal method. The porous sugarcane bagasse based biomass carbon was used as the host to load MnO2 nanospheres. The final obtained nanocomposites exhibit high specific capacitance. Besides, the effects of different electrolytes on the electrochemical properties of sugarcane bagasse carbon (SBC)/MnO2 nanosphere composites (SBC/MnO2) were also investigated. In comparison with MnO2 nanospheres, the specific capacitances of the SBC/MnO2 composite materials are improved whether in alkaline electrolyte or neutral electrolyte. Especially, in 1 M Na2SO4 electrolyte, the specific capacitance of SBC/MnO2 composite is up to 747 F·g−1 at a current density of 1 A·g−1, which is much higher than the MnO2 nanospheres at the same current density. At the same time, after 1000 cycles of charge–discharge process in a neutral electrolyte, the specific capacitance retention of SBC/MnO2 composite reaches 77%.