Department of Mechanical and Materials Engineering, University of Western Ontario, London, Ontario, Canada.
Phys Chem Chem Phys. 2013 Mar 14;15(10):3535-42. doi: 10.1039/c3cp44172e. Epub 2013 Feb 4.
Hierarchical carbon encapsulated tin (Sn@C) embedded graphene nanosheet (GN) composites (Sn@C-GNs) have been successfully fabricated via a simple and scalable one-step chemical vapor deposition (CVD) procedure. The GN supported Sn@C core-shell structures consist of a crystalline tin core, which is thoroughly covered by a carbon shell and more interestingly, extra voids are present between the carbon shell and the tin core. Synchrotron spectroscopy confirms that the metallic tin core is free of oxidation and the existence of charge redistribution transfer from tin to the carbonaceous materials of the shell, facilitating their intimate contact by chemical bonding and resultant lattice variation. The hybrid electrodes of this material exhibit a highly stable and reversible capacity together with an excellent rate capability, which benefits from the improved electrochemical properties of tin provided by the protective carbon matrix, voids and the flexible GN matrices.
通过简单且可扩展的一步化学气相沉积（CVD）程序，成功制备了分层碳封装锡（Sn@C）嵌入石墨烯纳米片（GN）复合材料（Sn@C-GNs）。GN 支撑的 Sn@C 核壳结构由结晶锡核组成，该核完全被碳壳覆盖，更有趣的是，在碳壳和锡核之间存在额外的空隙。同步辐射光谱证实，金属锡核没有氧化，并且存在电荷从锡到壳的碳质材料的重新分布转移，通过化学键合和由此产生的晶格变化促进它们的紧密接触。该材料的混合电极表现出高度稳定和可逆的容量以及优异的倍率性能，这得益于保护性碳基质、空隙和柔性 GN 基质提供的锡的电化学性能的提高。
