Facile Synthesis of Crumpled Nitrogen-Doped MXene Nanosheets as a New Sulfur Host for Lithium¿Sulfur Batteries

Crumpled nitrogen-doped MXene nanosheets with strong physical and chemical coadsorption of polysulfides are synthesized by a novel one-step approach and then utilized as a new sulfur host for lithium–sulfur batteries. The nitrogen-doping strategy enables introduction of heteroatoms into MXene nanosheets and simultaneously induces a well-defined porous structure, high surface area, and large pore volume. The as-prepared nitrogen-doped MXene nanosheets have a strong capability of physical and chemical dual-adsorption for polysulfides and achieve a high areal sulfur loading of 5.1 mg cm–2. Lithium–sulfur batteries, based on crumpled nitrogen-doped MXene nanosheets/sulfur composites, demonstrate outstanding electrochemical performances, including a high reversible capacity (1144 mA h g–1 at 0.2C rate) and an extended cycling stability (610 mA h g–1 at 2C after 1000 cycles).