Catalytic graphitization of bacterial cellulose–derived carbon nanofibers for stable and enhanced anodic performance of lithium-ion batteries

Abstract

Bacterial cellulose (BC) produced through microbial fermentation has emerged as a viable precursor for carbon nanofibers (CNF) anode used in lithium-ion batteries. However, the low capacity and fading behavior of BC-derived CNFs render their usage in its pure form. Tuning the microstructure of CNFs in such cases plays an essential role in overcoming these negative ramifications and improves battery performance. In this study, the fermentation media used for BC production is modified by the addition of an iron catalyst, which can induce graphitization in the derived CNFs. Pure BC and catalyst-incorporated BC are pyrolyzed at 900 °C and 1800 °C to obtain CNFs, and the properties of derived CNFs are compared for understanding the role of incorporated catalyst. The structural, morphological, and electrochemical properties of CNFs are analyzed through X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, impedance spectroscopy, galvanostatic charge-discharge studies, and cyclic voltammogram studies. By possessing a higher graphitic content, catalyst-incorporated BC–derived CNFs exhibit an enhanced rate performance with a reversible capacity of 529 mAh g−1 after 100 continuous charge/discharge cycles at a current density of 0.2C.