Cobalt and Molybdenum Carbide Nanoparticles Grafted on Nitrogen‐Doped Carbon Nanotubes as Efficient Chemical Anchors and Polysulfide Conversion Catalysts for Lithium‐Sulfur Batteries

Abstract The practical applications of lithium‐sulfur (Li−S) batteries are mainly hindered by the shuttle effect of soluble polysulfides and the slow kinetics of polysulfide conversion. Herein, a multi‐component material with cobalt and molybdenum carbide nanoparticles grafted on bamboo‐like N‐doped carbon nanotubes (Co−Mo 2 C@NCNTs) is fabricated and applied to modify the separator to suppress polysulfide migration and to promote polysulfide conversion. The uniformly distributed Co and Mo 2 C nanoparticles act as both the adsorbent to capture the polysulfides with Co−S and Mo−S bonds by Lewis acid‐base interactions and the catalyst to further accelerate the reaction kinetics of polysulfide transformation. Consequently, the Li−S batteries with the Co−Mo 2 C@NCNTs‐coated separator deliver a high specific capacity of 1324 mAh g −1 at 0.2 C and a capacity decay rate of 0.068 % per cycle at 1 C for 500 cycles. The results suggest the efficient chemical anchoring and catalysis of the multifunctional Co−Mo 2 C@NCNTs composite as a feasible method for future large‐scale applications of high‐performance Li−S batteries.