MoO3/MoS2 flexible paper as sulfur cathode with synergistic suppress shuttle effect for lithium-sulfur batteries

Lithium-sulfur (Li-S) batteries have become one of the most promising candidate systems for electronic energy storage applications. However, the shuttle effect, which is caused by the intermediate lithium polysulfide (LiPs) dissolving in the electrolyte and commuting between electrodes, is the main factor leading to the deterioration of the electrochemical performance of the Li-S batteries. Different from most single physical confinement or chemical adsorption, we report a hydrogen ion intercalated molybdenum trioxide (MoO3-HI) with embedded molybdenum disulfide (MoS2) flexible paper as S hosts not only restricted soluble LiPs passively with physical adsorption, but also accelerate actively the transformation rate of polysulfides with strong chemical affinity and catalytic activity. Furthermore, the theoretical calculation showed that the MoO3-HI/MoS2 equipped the ability of directly convert S-8 molecules into LiS2 molecules, eliminating the formation of lithium polysulfide. Based on the new strategy of synergistic suppress shuttle effect, the Li-S battery with MoO3-HI/MoS2/S cathode achieved a capacity of 911.3 mAh g(-1) after 500 cycles with outstanding cycle stability. In addition, MoO3-HI/MoS2 paper as a flexible carrier for Li-S batteries can be folded repeatedly and keep the structure intact. Hence, the current work provides a novel paper electrode with active and passive dual synergistic inhibition of shuttle effect characteristics for high performance flexible lithium-sulfur batteries.

Automated summary

A novel MoO3-HI/MoS2/S paper electrode has been developed to synergistically suppress the shuttle effect in Li-S batteries. The experimental results demonstrate that the Li-S battery with this electrode can maintain outstanding capacity and cycle stability after 500 cycles.