Interlaced Micro-Fibrous Hard Carbon As Superior Anode for Na-Ion Battery: Insights into the Sodium Storage Mechanism and Solid Electrolyte Interface

Hard carbon has been proved to be a promising negative electrode material for sodium-ion battery (SIBs) application. In this study, we have synthesized carbonaceous anode material by pyrolysis of tissue paper waste at different temperatures ranging from 800° to 1400°C. The tissue paper pyrolyzed at 1400°C has shown highest desodiation capacity of 350 mAhg-1 at 20 mAg-1 with stable cyclic performance and 70% capacity retention after 400 cycles at 200 mAg-1. The morphology, structure and surface chemistry of the cycled hard carbon electrodes were examined by ex-situ FE-SEM, XRD, Raman and XPS. The characterization results obtained reveal the detailed insights of the solid electrolyte interface and sodium storage mechanism of the hard carbon. The parameters of diffusion kinetics were evaluated by Electrochemical Impedance Spectroscopy (EIS) and CV analysis at different sweep rates. The results obtained in the study establish tissue paper waste as a promising precursor material to synthesize carbonaceous anode for SIBs by a simple one-step pyrolysis process.