Applied Surface Science, Vol.473, 540-547, 2019
Flower-like molybdenum disulfide/carbon nanotubes composites for high sulfur utilization and high-performance lithium-sulfur battery cathodes
Lithium-sulfur (Li-S) batteries have attracted an increasing attention for advanced energy storage devices, because of their high energy density, low cost and lower environmental impacts. However, their commercial applications are still hampered with the low conductivity and sulfur utilization, the low sulfur loading and the serious capacity fading at a high current rate. Herein, we prepared flower-like molybdenum disulfide and carbon nanotubes (MoS2/CNTs) composites with mesoporous structures for high sulfur utilization cathodes. The flowerlike MoS2 can immobilize sulfur and obstruct the solubility of polysulfide within the structures. The MoS2/CNTs-S cathode with 2.6 mg cm(-2) sulfur loading and capacity per area of 3.83 mA h cm(-2) delivers an initial specific discharge capacity of 1473 mA h g(-1) with 88.0% sulfur utilization and maintains a reversible capacity of 855.5 mA h g(-1) with coulombic efficiency up to 96.6% after 50 cycles at the current rate of 0.2 C (335.0 mA g(-1)). Impressively, the MoS2/CNTs-S cathode at 5C shows the high specific capacity of 1254 mA h g(-1) with 76.0% sulfur utilization and maintains 384.0 mA h g(-1) with an average coulombic efficiency of 91% after 200 cycles. The MoS2/CNTs-S cathode could be a good candidate for high-performance Li-S battery.