Tungsten Oxide Nanowire/Carbon Nanotube Interlayer As a Polysulfide Mediator for High-Performance Lithium-Sulfur Batteries

Abstract

In this study, we designed a new nanaowire to enhance the performance of lithium-sulfur batteries. Tungsten oxide nanowires (WNWs) were synthesized via a simple hydrothermal method. WNWs and one-dimensional materials easily mix with carbon nanotubes (CNTs) to form interlayers. The WNW interacts with lithium polysulfides as a thiosulfate mediator by positioning the lithium polysulfide near the cathode to increase the reaction kinetics. The lithium-sulfur cell with WNW/CNT interlayer achieves a very high initial discharge capacity of 1558 mAh g-1 and 656 mAh g-1 at 0.1 C and 3 C, respectively. Moreover, a cell with a high sulfur mass loading of 4.2 mg cm-2, still delivers a high capacity of 1136 mAh g-1 at a current density of 0.2 C. This excellent performance and structural stability are due to the chemical adsorption and catalytic effects of the thiosulfate mediator on WNW.References Hwang, J.-Y.; Kim, H. M.; Shin, S.; Sun, Y.-K., Adv. Funct. Mater. 2018, 28, 1704294. Lin, H. B.; Zhang, S. L.; Zhang, T. R.; Ye, H. L.; Yao, Q. F.; Zheng, G. W.; Lee, J. Y., Adv. Energy Mater. 2018, 8, 1801868. Kumar, R.; Liu, J.; Hwang, J.-Y.; Sun, Y.-K., J. Mater. Chem. A 2018, 6, 11582-11605.