Zincothermic-Reduction-Enabled Harvesting of an Si/C Composite from Rice Husks for a Li-Ion Battery Anode

Abstract

Harvesting Si-based anode materials from environmentally friendly and abundant Si-containing natural resources not only meets the needs of the constantly widening Li-ion battery (LIB) markets but also promotes the utilization of agricultural waste. Herein, we report the fabrication of an Si/C composite derived from rice husks (RHs) via a low-temperature AlCl 3 -assisted zincothermic reduction. Thermodynamically, the bio-SiO 2 blended with a carbon matrix is first transformed to SiCl 4 and then reduced by Zn powder to produce Si nanoparticles. Due to the internal contact of bio-Si and C derived from RHs, the prepared Si/C composite displays an outstanding electrochemical performance; a capacity of 1033 mAh g −1 can be achieved over 100 cycles under 1 A g −1 with 6.6% capacity loss. What is more, the capacity of the Si/C composite can be maintained at 745 mAh g −1 over 250 cycles under 2 A g −1 . In this work, a novel approach is developed to synthesize Si/C composites with the utilization of sustainable biomass resources for LIB anodes, enabling a high-value-added conversion for Si-based agricultural waste.

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Preparation of Hollow Nanostructured Si Spheres by Zincothermic Reduction of SiO2 to Si for Lithium-Ion Batteries

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