Pang Haibo, Zhang Weicai, Yu Peifeng, Pan Ning, Hu Hang, Zheng Mingtao, Xiao Yong, Liu Yingliang, Liang Yeru
College of Materials and Energy, Guangdong Provincial Engineering Technology Research Center for Optical Agriculture, South China Agricultural University, Guangzhou 510642, China.
Guangdong Laboratory of Lingnan Mordern Agriculture, Guangzhou 510642, China.
Nanomaterials (Basel). 2020 Mar 12;10(3):513. doi: 10.3390/nano10030513.
Recently, SiO has attracted wide attention in lithium-ion batteries owing to its high theoretical capacity and low cost. However, the utilization of SiO is impeded by the enormous volume expansion and low electric conductivity. Although constructing SiO/carbon composite can significantly enhance the electrochemical performance, the skillful preparation of the well-defined SiO/carbon composite is still a remaining challenge. Here, a facile strategy of in situ coating of polydopamine is applied to synthesis of a series of core-shell structured SiO@carbon composite nanorods with different thicknesses of carbon shells. The carbon shell uniformly coated on the surface of SiO nanorods significantly suppresses the volume expansion to some extent, as well as improves the electric conductivity of SiO. Therefore, the composite nanorods exhibit a remarkable electrochemical performance as the electrode materials of lithium-ion batteries. For instance, a high and stable reversible capacity at a current density of 100 mA g reaches 690 mAh g and a capacity of 344.9 mAh g can be achieved even at the high current density of 1000 mA g. In addition, excellent capacity retention reaches 95% over 100 cycles. These SiO@carbon composite nanorods with decent electrochemical performances hold great potential for applications in lithium-ion batteries.
最近，二氧化硅（SiO）因其高理论容量和低成本在锂离子电池中受到广泛关注。然而，SiO的应用受到巨大体积膨胀和低电导率的阻碍。尽管构建SiO/碳复合材料可以显著提高其电化学性能，但制备结构明确的SiO/碳复合材料仍然是一个挑战。在此，采用一种简便的原位包覆聚多巴胺的策略合成了一系列具有不同碳壳厚度的核壳结构SiO@碳复合纳米棒。均匀包覆在SiO纳米棒表面的碳壳在一定程度上显著抑制了体积膨胀，同时提高了SiO的电导率。因此，作为锂离子电池的电极材料，复合纳米棒表现出卓越的电化学性能。例如，在100 mA g的电流密度下，其高且稳定的可逆容量达到690 mAh g，即使在1000 mA g的高电流密度下，容量也能达到344.9 mAh g。此外，在100次循环中，优异的容量保持率达到95%。这些具有良好电化学性能的SiO@碳复合纳米棒在锂离子电池应用中具有巨大潜力。
