CSIRO Manufacturing, PO Box 218, 36 Bradfield Road, Lindfield, NSW 2070, Australia. Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, University of Technology Sydney, NSW 2007, Australia.
Nanotechnology. 2019 Jan 18;30(3):035401. doi: 10.1088/1361-6528/aaec4d. Epub 2018 Nov 16.
WS nanotubes with carbon coatings in a core-shell structure (i.e. WS@C) are synthesized through a facile method based on the Lewis acid-activated thioglycosylation chemistry. The obtained WS@C shows a conformal coverage of conductive amorphous carbon on the surface of WS after thermal treatment, with the thickness of carbon layer being controlled by adjusting the molar ratios of saccharide to nanotube during the synthesis process. When applied in lithium-ion batteries, the WS@C structures show higher reversible capacity of 638 mAh g at a current density of 500 mA g and significantly improved cycling stability as compared to the pristine WS nanotubes. Post-mortem examinations of the electrode materials reveal that the carbon coatings could preserve the morphology of WS nanotubes and assist in forming stable solid electrolyte interface layers, leading to enhanced cycling stability. As such, the WS@C structures show great potential in the application of lithium-ion batteries for achieving excellent electrochemical performances.
WS 纳米管具有核壳结构的碳涂层（即 WS@C），通过基于路易斯酸激活的硫糖苷化学的简便方法合成。所得 WS@C 在热处理后，在 WS 表面表现出导电非晶碳的保形覆盖，碳层的厚度可以通过在合成过程中调整糖与纳米管的摩尔比来控制。将其应用于锂离子电池中时，与原始 WS 纳米管相比，WS@C 结构在 500 mA g 的电流密度下具有更高的可逆容量 638 mAh g，并且显著提高了循环稳定性。对电极材料的事后检查表明，碳涂层可以保持 WS 纳米管的形态，并有助于形成稳定的固体电解质界面层，从而提高循环稳定性。因此，WS@C 结构在锂离子电池的应用中具有很大的潜力，可以实现优异的电化学性能。
