Enhanced electrochemical performance of SnS nanoparticles/CNTs composite as anode material for sodium-ion battery
Enhanced electrochemical performance of SnS nanoparticles/CNTs composite as anode material for sodium-ion battery
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DOI：
10.1016/j.cclet.2017.06.019
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发表时间：
2018
影响因子：
9.1
通讯作者：
Yuanyuan Chen;Bingjie Wang;Tianyi Hou;Xudong Hu;Xin Li;Xiaohong Sun;Shu Cai;Huiming Ji;
中科院分区：
文献类型：
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作者：
Yuanyuan Chen;Bingjie Wang;Tianyi Hou;Xudong Hu;Xin Li;Xiaohong Sun;Shu Cai;Huiming Ji;
采用一锅法合成了SnS纳米粒子/CNTs复合材料（SnS/CNTs复合材料）。结构表征表明，粒径小于10 nm的纯SnS纳米粒子分布在直径小于20 nm的碳纳米管表面。SnS/CNTs复合电极具有较高的可逆容量和良好的循环性能（在50 mA/g下50次循环后为365 mAh/g），上级未添加CNTs的纯SnS电极（在50 mA/g下50 mA/g循环后为115.9 mAh/g）。即使将电流密度增加到500 mA/g，SnS/CNT复合电极在100次循环后仍然提供高达210 mAh/g的可逆容量，比纯SnS电极（100次循环后108 mAh/g）高近两倍。在50 ~ 800 mA/g的电流密度下，SnS/CNTs复合电极的倍率性能也优于纯SnS电极。SnS/CNTs复合材料电化学性能的提高主要归因于CNTs作为柔性导电结构载体的加入和小尺寸SnS纳米粒子的形成。SnS纳米颗粒/CNT复合结构不仅有利于缓冲充放电过程中的体积变化，而且增加了电极与电解质充分接触的表面积，缩短了Na+扩散长度，从而提高了活性材料的导电性和稳定性，最终提供了理想的电化学性能。
SnS nanoparticles/CNTs composite (SnS/CNTs composite) is synthesized by a facile one-pot solvothermal reaction. The structural characterizations reveal pure SnS nanoparticles with the size of less than 10 nm distribute on the surface of CNTs with the diameter of less than 20 nm. The SnS/CNTs composite electrode performs high reversible capacity and good cyclability (365 mAh/g at 50 mA/g after 50 cycles), which is superior to that of pure SnS electrode synthesized without the adding of CNTs (115.9 mAh/g at 50 mA/g after 50 mA/g cycles). Even increasing the current density to 500 mA/g, the SnS/CNTs composite electrode still delivers a reversible capacity up to 210 mAh/g after 100 cycles, nearly two times higher than that of the pure SnS electrode (108 mAh/g after 100 cycles). The rate performance of the SnS/CNTs composite electrode is also better than that of pure SnS electrode at different current densities from 50 mA/g to 800 mA/g. The enhanced electrochemical performance of SnS/CNTs composite can be attributed to the adding of CNTs as a flexible and conductive structure supporter and the formation of SnS nanoparticles with small size. The SnS nanoparticles/CNTs composite structure not only benefits for buffering the volume change during charge and discharge process, but also increases the surface area for sufficient electrode-electrolyte contacting, and shortens Na+diffusion length, which improves the conductivity and stability of active material and finally provides desirable electrochemical performance.