Department of Mechanical Engineering, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA.
Nanoscale. 2014 Jan 7;6(1):342-51. doi: 10.1039/c3nr04162j. Epub 2013 Nov 7.
This study aims to realize controllable synthesis of Si-based nanostructures from common and easily accessible silica nanoparticles and to study their component/structure-dependent electrochemical performance as an anode of lithium-ion batteries (LIBs). To this end, a controllable route based on deliberate design has been developed to prepare hollow Si-based nanospheres with tunable composition and crystal structure at the nanoscale. The synthesis process started with coating silica nanoparticles with a carbonaceous polymer with a controllable thickness followed by magnesiothermic reduction. An Si-SiC-C composite was finally produced with a unique hollow sphere structure featuring Si-SiC nanoparticles encapsulated by a cross-linked carbon film network. In addition to the scalability of the synthetic route, the resulting composite exhibits a number of advantageous properties, including excellent electrical conductivity, highly accessible surfaces, structural coherence, and a favorable structure for the formation of a stable solid-electrolyte interphase, which makes it attractive and promising for advanced anode materials of LIBs.
本研究旨在实现从常见且易于获得的二氧化硅纳米粒子可控合成硅基纳米结构，并研究其成分/结构依赖性电化学性能作为锂离子电池 (LIBs) 的阳极。为此，开发了一种基于精心设计的可控途径，以在纳米尺度上制备具有可调组成和晶体结构的空心硅基纳米球。该合成过程从用可控厚度的碳质聚合物涂覆二氧化硅纳米粒子开始，然后进行镁热还原。最后，采用独特的空心球结构制备了 Si-SiC-C 复合材料，其特征在于 Si-SiC 纳米颗粒被交联碳膜网络包裹。除了合成路线的可扩展性之外，所得到的复合材料还具有许多有利的特性，包括优异的导电性、高可及表面、结构连贯性以及有利于形成稳定的固体电解质界面的结构，这使其成为有吸引力和有前途的先进锂离子电池阳极材料。
