Simplified Synthesis of Biomass‐Derived Si/C Composites as Stable Anode Materials for Lithium‐Ion Batteries

Abstract

Synthesis of silicon/carbon (Si/C) composites from biomass resources could enable the effective utilization of agricultural products in the battery industry with economical as well as environmental benefits. Herein, a simplified process was developed to synthesize Si/C from biomass, by using a low‐cost agricultural byproduct “rice husk (RH)” as a model. This process includes the calcination of RH for SiO2/C and the reduction of SiO2/C by Al in molten salts at a moderate temperature. This process does not need the removal of carbon before thermal reduction of SiO2, which is thought to be necessary to avoid the formation of SiC at elevated temperatures. Thus, carbon derived from biomass can be directly used for Si/C composites for anode materials. The resultant Si/C shows a high reversible capacity of 1309 mAh g−1 and long cycle life (300 cycles). This research advocates a new and simplified strategy for the synthesis of RH‐based biomass‐derived Si/C, which is beneficial for low‐cost, environmentally friendly, and green energy storage applications.

Biomass-Based Silicon and Carbon for Lithium-Ion Battery Anodes

“…This composite electrode displayed superior performance compared to RH-carbon and RH-Si ( Figure 2D ) ( Yu et al, 2018 ). Majeed et al also synthesized porous Si/C composite from RH by aluminothermic reduction at a lower temperature ( Figure 2E ), which exhibited good electrochemical performance ( Figures 2F–J ) compared to RH-Si ( Majeed et al, 2020 ). Therefore, the development of Si/C anode from biomass raw materials appears to be the most reliable strategy for the future, considering its economic value and eco-friendly aspect.…”

“…Electrochemical performance of Si/C composite: (F) CV curves, (G) charge/discharge curves, (H) cycling performance at 200 mAg −1 , (I) rate capabilities at different current densities, and (J) cycling stability at 500 mAg −1 . Modified with permission from ( Majeed et al, 2020 ). Copyright © 2000–2022 by John Wiley & Sons, Inc.…”

Reconstructed Nano-Si Assembled Microsphere via Molten Salt-Assisted Low-Temperature Aluminothermic Reduction of Diatomite as High-Performance Anodes for Lithium-Ion Batteries

“…Therefore, converting the cheap mineral silicon source to Si becomes a pressing issue. To date, waste windshield, white carbon black, rice husk, diatomite, and so on have been used as silicon sources to synthesize Si-based materials. Among them, diatomite is a kind of biological sedimentary mineral and distributed widely in the world, especially in China.…”

“…Simultaneously, the decrease of temperature also reduces energy consumption, benefiting the reduction of manufacturing cost. However, either magnesium thermal reduction or aluminum thermal reduction cannot control the morphology after reduction, generally nanoparticles and irregular big block. , The large surface of the nanoparticles and the large grain size of irregular big block lead to low coulombic efficiency and bad cycle performance, respectively, which are not conducive to application. A stable novel structure should be explored to achieve high performance of the Si anode.…”

Scalable Synthesis of Porous SiFe@C Composite with Excellent Lithium Storage

“…Moreover, the relative complexity, low yield, and high cost in the synthesis process of nanosilicon have largely hindered large‐scale commercial applications. Another strategy is to combine silicon with other components to prepare core–shell, [9] yolk–shell, [19] and porous structures [20] of silicon‐based composites, such as silicon/carbon composites, [4, 21–24] silicon/metal composites, [25] silicon/metal oxide composites, [26] and silicon/conductive polymer composites [27, 28] . The above research ideas have been extensively investigated, but it still requires further exploration to achieve large‐scale industrial production due to complicated synthesis processes and high cost.…”