Carbon–Manganese Oxide Composite Derived from Wheat Flour: Kitchen-Inspired Green Synthesis and Applications in Energy Storage

Abstract

The quest for better alternatives for graphite anodes is the holy grail in the field of energy storage technologies. Biomass-derived carbon has been widely explored as the energydense and cost-effective option but involves several pre/postconditioning steps. In this study, kitchen chemistry concepts of fermentation have been utilized to obtain sustainable carbon anodes from readily available and cost-effective wheat flour and baker's yeast. The yeast-fermented mixture of wheat flour and MnCO 3 is pyrolyzed under 500 °C to yield porous C-MnO composites, which have been explored as an anode for Li-ion batteries. The material showed superior electrochemical performance with an initial discharge of 1160 mAh g −1 at 0.15 A g −1 (after solid electrolyte interface formation). A reversible capacity of 1499 mAh g −1 was obtained with a concomitant improvement of 30% after 160 cycles exhibiting a "negative fading effect". Excellent electrochemical behavior has been attributed to the synergistic effect of in situ synthesized, well-dispersed MnO in carbon, the presence of redox-active Mn, and well-connected porosity in nanohybrids. At a high current density of 1 A g −1 , the anode displayed an exemplary initial discharge capacity of 770 mAh g −1 with a high initial Coulombic efficiency of 90%, which was maintained at 856 mAh g −1 after 760 cycles. Easy synthesis and excellent electrochemical performance render this material highly promising for battery applications.

Enhanced Lithium Storage Performance: Dual-Modified Electrospun Si@MnO@CNFs Composites for Advanced Anodes

“…The Si@MnO@CNFs electrode’s formation of the SEI film during the first discharge is the primary source of Li . Three subpeaks are visible in the high-resolution C 1s XPS spectrum (Figure b), including CC, which is centered at about 284.8 eV and peaks at 282.9 and 287.2 eV, which represents the carbide of Mn 3+ and the C–O of the carbon matrix that has been adsorbed with oxygen . Three subpeaks were seen in the high-resolution O 1s XPS spectrum (Figure c).…”