Abstract:
In this present work, hard carbons were synthesized from local Indonesian starch by using hydrothermal carbonization followed by the activation process at high temperature. It was found that as obtained hard carbons showed a sheet like morphology, a well-connected structure and a large interlayer spacing. The hard carbons were then utilized as anode materials for sodium ion battery. The electrochemical characterizations were examined by cyclic voltammetry (CV), galvanostatic charge discharge and electrochemical impedance spectroscopy. The best hard carbon sample performed a stable cycle profiles, maintaining a high specific capacity of around 180 mAh g-1 until the 100th cycle at a current density of 100 mAg-1 These very good performances were ascribed to the large interspacing of hard carbons, carbon defect structure and sheet like morphology which can provide a large space for sodium storage and facilitate sodium ion transfer.
