Institute for Clean Energy & Advanced Materials, Faculty of Materials and Energy , Southwest University , Chongqing 400715 , PR China.
Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies , Chongqing 400715 , P.R. China.
ACS Appl Mater Interfaces. 2018 Dec 19;10(50):43707-43715. doi: 10.1021/acsami.8b16948. Epub 2018 Dec 7.
Inhibiting the shuttle effect, buffering the volume expansion, and improving the utilization of sulfur have been the three strategic points for developing a high-performance lithium-sulfur (Li-S) battery. Driven by this background, a flexible sulfur host material composed of FeCoS nanotube arrays grown on the surface of carbon cloth is designed for a binder-free cathode of the Li-S battery through two-step hydrothermal method. Among the rest, the interconnected carbon fiber skeleton of the composite electrode ensures the basic electrical conductivity, whereas the FeCoS nanotube arrays not only boost the electron and electrolyte transfer but also inhibit the dissolution of polysulfides because of their strong chemical adsorption. Meanwhile, the hollow structures of these arrays can provide a large inner space to accommodate the volume expansion of sulfur. More significantly, the developed composite electrode also reveals a catalytic action for accelerating the reaction kinetic of the Li-S battery. As a result, the FeCoS/CC@S electrode delivers a high discharge capacity of 1384 mA h g at the current density of 0.1 C and simultaneously exhibits a stable Coulombic efficiency of about 98%.
抑制穿梭效应、缓冲体积膨胀和提高硫的利用率一直是开发高性能锂-硫（Li-S）电池的三个战略要点。受此背景驱动，通过两步水热法设计了一种由生长在碳纤维布表面的 FeCoS 纳米管阵列组成的柔性硫主体材料，用作无粘结剂 Li-S 电池的阴极。在其余部分中，复合电极的互连碳纤维骨架确保了基本的导电性，而 FeCoS 纳米管阵列不仅由于其强化学吸附而促进了电子和电解质的转移，而且抑制了多硫化物的溶解。同时，这些阵列的中空结构可以提供大的内部空间来容纳硫的体积膨胀。更重要的是，所开发的复合电极还表现出加速 Li-S 电池反应动力学的催化作用。因此，FeCoS/CC@S 电极在 0.1 C 的电流密度下提供了 1384 mA h g 的高放电容量，同时表现出约 98%的稳定库仑效率。
