School of Materials Science and Engineering, University of Shanghai for Science & Technology , Shanghai 200093, China.
ACS Appl Mater Interfaces. 2017 Feb 1;9(4):3544-3553. doi: 10.1021/acsami.6b10807. Epub 2017 Jan 17.
A unique 3D graphene-single walled carbon nanotube (G-SWNT) aerogel anchored with SnO nanoparticles (SnO@G-SWCNT) is fabricated by the hydrothermal self-assembly process. The influences of mass ratio of SWCNT to graphene on structure and electrochemical properties of SnO@G-SWCNT are investigated systematically. The SnO@G-SWCNT composites show excellent electrochemical performance in Li-ion batteries; for instance, at a current density of 100 mA g, a specific capacity of 758 mAh g was obtained for the SnO@G-SWCNT with 50% SWCNT in G-SWCNT and the Coulombic efficiency is close to 100% after 200 cycles; even at current density of 1 A g, it can still maintain a stable specific capacity of 537 mAh g after 300 cycles. It is believed that the 3D G-SWNT architecture provides a flexible conductive matrix for loading the SnO, facilitating the electronic and ionic transportation and mitigating the volume variation of the SnO during lithiation/delithiation. This work also provides a facile and reasonable strategy to solve the pulverization and agglomeration problem of other transition metal oxides as electrode materials.
通过水热自组装工艺制备了一种独特的 3D 石墨烯-单壁碳纳米管（G-SWNT）气凝胶，其中锚定了 SnO 纳米粒子（SnO@G-SWCNT）。系统研究了 SWCNT 与石墨烯的质量比对 SnO@G-SWCNT 的结构和电化学性能的影响。SnO@G-SWCNT 复合材料在锂离子电池中表现出优异的电化学性能；例如，在 100 mA g 的电流密度下，具有 50% SWCNT 在 G-SWCNT 中 SnO@G-SWCNT 的比容量为 758 mAh g，经过 200 次循环后库仑效率接近 100%；即使在 1 A g 的电流密度下，经过 300 次循环后仍能保持稳定的比容量为 537 mAh g。相信 3D G-SWNT 结构为负载 SnO 提供了一个灵活的导电基质，有利于电子和离子的传输，并减轻了 SnO 在锂化/脱锂过程中的体积变化。这项工作还为解决其他过渡金属氧化物作为电极材料的粉碎和团聚问题提供了一种简单合理的策略。
