Insights into the electrochemical properties of bagasse-derived hard carbon anode materials for sodium-ion battery

Bio-derived Hard Carbon is a proven negative electrode material for sodium ion battery (SIB). In the present study, we report synthesis of carbonaceous anode material for SIBs by pyrolyzing sugarcane bagasse, an abundant biowaste. Sugarcane bagasse contains carbon-rich compounds e.g., hemicellulose, lignin and cellulose which prevent graphitization of carbon on pyrolysis. The prepared material is highly disordered, porous with flake-like structures and has enhanced interplanar spacing which facilitate the faster Na ion transport and enhanced sodium storage as evidenced by the excellent electrochemical characteristics of the hard carbon pyrolyzed at 900 °C (SW 900) showing highest 2nd cycle discharge capacity of 300 mAhg−1 at 25 mAg−1. Even after subjecting the SW 900 for 300 cycling at 100 mAg−1, the capacity of over 65% is found. This confirms sugarcane waste as a suitable hard carbon anode material for SIB application. The sodium storage mechanism of the hard carbon contributing to the slope and the plateau capacity has been studied in detail.