F‐Free Fabrication Novel 2D Mo‐Based MBene Catalyst for Advanced Lithium–Sulfur Batteries

Abstract An efficient electrocatalytic medium is very important for lithium–sulfur (Li–S) batteries. Herein, as a novel MBene‐based material, 2D MoB is employed to facilitate the catalytic conversion of lithium polysulfides (LiPSs). Instead of the HF etching technology of previous MXene, the accordion‐like MoB‐based MBene adopts a hydrothermal‐assisted process. Its F‐free surface property prevents the harm of negative sulfur cathode from −F terminations. The high charge conductivity and abundant electrocatalytic active sites promote the adsorption‐transfer conversion of LiPSs on the MoB surface and accelerate the redox kinetics. Theoretical calculation, visual detection and in situ Raman results show that the stratified MoB‐coated separator inhibits the “shuttle effect” of soluble LiPSs through the coupling of physical and chemical mechanisms. Therefore, this work achieves a commendable stability of 847 mAh g −1 reversible capacity (2.0 C) and 0.0651% attenuation rate per cycle (4.0 C). The area capacity of 4.93 mAh cm −2 is still obtained under high loading. More importantly, this work has uncovered the great potential of promising 2D MBene as a catalyst for the reaction of sulfur species.