Hydrothermal Synthesis of Porous Sugarcane Bagasse Carbon/MnO2 Nanocomposite for Supercapacitor Application

In this article, we reported a biomass carbon/MnO2 nanocomposite electrode material prepared by a hydrothermal method. Sugarcane bagasse and KOH were the carbon source and activation agent, respectively. The obtained sugarcane bagasse carbon is rich in pore structure, so it can act as the host for MnO2. The biomass carbon/MnO2 nanocomposite electrode was prepared by a hydrothermal method. The morphologies of materials were observed by scanning electron microscopy. Raman spectra and x-ray diffraction were utilized to characterize the molecular and crystal structures of samples, respectively. The electrochemical and capacitive performances of materials were tested by electrochemical workstation. By calculation, the specific capacitance of sugarcane bagasse carbon, MnO2 and composite electrode are 280 F g−1, 163 F g−1 and 359 F g−1, respectively. Compared with pure sugarcane bagasse carbon and MnO2, the specific capacitance of the composite increases by 28% and 120%, respectively. After 2000 cycles of charge and discharge, the capacitance retention of the composite is 94%, which is higher than 91% of sugarcane bagasse carbon and 45% of MnO2.