The Impact of Oxygen Content in O‐Doped MoS2 on the Kinetics of Polysulfide Conversion in Li–S Batteries

Abstract Polysulfide shuttle and sluggish sulfur redox kinetics remain key challenges in lithium–sulfur batteries. Previous researches have shown that introducing oxygen into transition metal sulfides helps to capture polysulfides and enhance their conversion kinetics. Based on this, further investigations are conducted to explore the impact of oxygen doping levels on the physical‐chemical properties and electrocatalytic performance of MoS 2 . The findings reveal that MoS 2 doped with high‐content oxygen exhibits enhanced conductivity and polysulfides conversion kinetics compared to MoS 2 with low‐content oxygen doping, which can be attributed to the alteration of crystal structure from 2H‐phase to the 1T‐phase, the introduction of increased Li–O interactions, and the effect of defects resulting from high‐oxygen doping. Consequently, the lithium–sulfur batteries using high‐oxygen doped MoS 2 as a catalyst deliver a high discharge capacity of 1015 mAh g −1 at 0.25C and maintain 78.5% capacity after 300 more cycles. Specifically, lithium–sulfur batteries employing paper‐based electrodedemonstrate an areal capacity of 3.91 mAh cm −2 at 0.15C, even with sulfur loading of 4.1 mg cm −2 and electrolyte of 6.7 µL mg −1 . These results indicate that oxygen doping levels can modify the properties of MoS 2 , and high‐oxygen doped MoS 2 shows promise as an efficient catalyst for lithium–sulfur batteries.