SiO₂/C Composite Derived from Rice Husks with Enhanced Capacity as Anodes for Lithium‐Ion Batteries

Abstract

High‐capacity SiO2/C composites with uniform distribution, rice husks (RHs) as raw materials, were scalably prepared by the ball milling method. Based on a fact that the porous SiO2 nanoparticles and carbon in RHs possess natural properties, ball mill could visibly decrease grain sizes of clustering SiO2 particles and C blocks and then improve the dispersivity of the two components, finally forming desirable SiO2/C composite, which can generate more active sites for Li+ storage as well as can effectively buffer the volume change during cycling. Therefore, SiO2/C composites, evaluated as anode for lithium ion batteries, exhibited an excellent electrochemical performance, especially the highly reversible capacity of 827 mA h g−1 over 300 cycles at 100 mA g−1 and 530 mA h g−1 at the large rate of 500 mA g−1, which suggests that the facile ball mill with environmental friendliness and large‐scale preparation may be available for electrode materials derived from biomass.

In Situ‐Derived Porous SiO2/Carbon Nanocomposite from Lichens for Lithium‐Ion Batteries

“…The discharge capacity is gradually recovered to 617.9 mAh g −1 (40th cycle), stably retained at 583.3 mAh g −1 after 100 cycles, indicating good reversibility and the satisfying cycling stability. The capacity of SiO 2 /carbon after “acid‐washing” in this work is also compared with other works . While our results are comparable with the composite generated from rice husk by Feng et al and better than the result illustrated by Ju et al.…”

“…Among the numerous carbon materials, biochar is of particular interest because of its low cost and material consistency, which can be realized from abundant and nontoxic biomass precursors . Various precursors, such as lignin, pomelo pericarp, rice husk, litchi shells, and peanut shells, have been used to prepare biochar, which was commonly carbonized at 500–900 °C under argon atmosphere and followed by acid or alkaline‐washing to remove the impurities, and then applied in LIBs as high‐capacity electrode materials . Thus, the fabrication of SiO 2 /carbon composite will be a highly attractive idea.…”

N‐Enriched Porous Carbon/SiO2 Composites Derived from Biomass Rice Husks for Boosting Li‐Ion Storage: Insight into the Effect of N‐Doping

“…There is no doubt that the primary silica nanoparticles (20–50 nm) are sufficiently feasible to act as active anode material and the distinctly uneven dispersity between silica and carbon must to be further solved. As reported in our previous work, [15a] ball milling has been proved to be a facile and effective method to improve the structural relationship of silica and carbon of RHs (Figure S5b). In this work, the high‐level nitrogen was successfully doped by pretreatment by ball milling.…”

Carbon-Coated SiO2 Composites as Promising Anode Material for Li-Ion Batteries

“…The anode of a Li-ion battery should operate at low potentials and offer high specific energy capacity and density. However, several drastic challenges prevent the practical application of silicon anodes such as its huge (300%) volume change upon full lithiation, which causes the solid electrolyte interface (SEI) rupture or particle pulverization, leading to loss of electrical contact, fast reversible capacity loss, and low coulombic efficiency [ 2 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. In recent years, research interest toward SiO 2 -based materials as a promising new alternative to graphite has been significantly increased due to the high theoretical capacity and low discharge potential similar to pure silicon.…”