Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China.
Nanoscale. 2013 Feb 21;5(4):1576-82. doi: 10.1039/c2nr33482h.
We explore a hybrid material consisting of SnO(2) nanoparticles (NPs) embedded in the porous shells of carbon cages (SnO(2)-PSCC). The hybrid material exhibits improved kinetics of lithiation-delithiation and high reversible capacity, and excellent cyclic stability without capacity loss over 100 cycles at 500 mA g(-1) with a coulombic efficiency close to 100% after the initial cycle. This can be ascribed to the high electrical conductivity, the hierarchical porosity and the confinement effect of the PSCC on the volume change of SnO(2) NPs. The material has a large reversible capacity of 460 mA h g(-1) at a high current density of 5 A g(-1) due to a short ion diffusion length in the bulk and large number of inter-pore ion transport channels. These results provide insight into improving the lithium storage performance of SnO(2) by facilitating the reaction kinetics and indicate that this hybrid material has great potential for use in high-rate and durable lithium ion batteries.
我们探索了一种由嵌入在多孔碳笼壳中的 SnO(2)纳米颗粒 (NPs) 组成的混合材料 (SnO(2)-PSCC)。该混合材料表现出改善的锂化-脱锂动力学和高可逆容量，以及优异的循环稳定性，在 500 mA g(-1) 的电流密度下经过 100 次循环后没有容量损失，初始循环后库仑效率接近 100%。这可以归因于 PSCC 对 SnO(2) NPs 体积变化的高导电性、分级多孔性和限制作用。由于在体相中有较短的离子扩散长度和大量的孔间离子输运通道，该材料在高电流密度 5 A g(-1) 下具有 460 mA h g(-1) 的大可逆容量。这些结果为通过促进反应动力学来提高 SnO(2) 的储锂性能提供了深入的了解，并表明这种混合材料在高倍率和长寿命锂离子电池中有很大的应用潜力。
