School of Chemical Engineering and Technology and ‡Department of Chemistry, School of Science, Tianjin University , Tianjin 300350, China.
ACS Appl Mater Interfaces. 2018 Feb 7;10(5):4715-4725. doi: 10.1021/acsami.7b16760. Epub 2018 Jan 23.
The utilization of silicon/carbon composites as anode materials to replace the commercial graphite is hampered by their tendency to huge volumetric expansion, costly raw materials, and complex synthesis processes in lithium-ion batteries. Herein, self-assembly method is successfully applied to prepare hierarchical silicon nanoparticles@oxidized mesocarbon microbeads/carbon (Si@O-MCMB/C) composites for the first time, in which O-MCMB core and low-cost sucrose-derived carbon shell not only effectively enhance the electrical conductivity of the anode, but also mediate the dramatic volume change of silicon during cycles. At the same time, the carbon can act as "adhesive", which is crucial in enhancing the adhesive force between Si and O-MCMB in the composites. The as-obtained Si@O-MCMB/C delivers an initial reversible capacity of 560 mAh g at 0.1 A g, an outstanding cyclic retention of 92.8% after 200 cycles, and respectable rate capability. Furthermore, the synthetic route presented here is efficient, less expensive, simple, and easy to scale up for high-performance composites.
硅/碳复合材料作为锂离子电池的阳极材料来替代商业石墨，但其存在巨大的体积膨胀、昂贵的原材料和复杂的合成工艺等问题。在此，我们首次成功应用自组装法制备了分级硅纳米颗粒@氧化中间相炭微球/碳（Si@O-MCMB/C）复合材料，其中 O-MCMB 核和低成本蔗糖衍生的碳壳不仅有效地提高了阳极的导电性，而且还可以缓解硅在循环过程中的剧烈体积变化。同时，碳可以作为“粘合剂”，这对于增强复合材料中硅和 O-MCMB 之间的粘接力至关重要。所获得的 Si@O-MCMB/C 在 0.1 A g 时具有 560 mAh g 的初始可逆容量，在 200 次循环后具有 92.8%的出色循环保持率和良好的倍率性能。此外，这里提出的合成路线高效、廉价、简单，易于大规模制备高性能复合材料。
