Heterointerface engineering for dual-enhanced polysulfides regulation in high-energy-density lithium-sulfur batteries

The practical application of lithium‑sulfur (Li-S) batteries is severely hindered by the notorious polysulfides shuttle effect and sluggish redox kinetics. Herein, we propose a semi-lattice-matched NiO-NiS heterointerface engineered with excellent polysulfides adsorption capability and catalytic activity for boosting sulfur redox conversion in Li-S batteries. The excellent structural stability of NiO can effectively suppress the phase degradation of NiS during redox cycling, thereby providing long-term preservation of its catalytic activity. More importantly, NiO and NiS form a semi-lattice-matched structure, which not only facilitates efficient electron transport but also provides additional catalytic active sites. Therefore, the fabricated cell exhibits excellent rate performance and outstanding cycling stability. The NiO-NiS cell retains 78.0 % capacity over 100 cycles at a high current density of 2.76 mA cm −2 , while achieving an impressive areal capacity of 4.33 mA h cm −2 even with high sulfur content of 86 wt% at 0.55 mA cm −2 . This study offers valuable insights and novel perspectives for the rational design of heterointerfaces in high-energy-density Li-S batteries. A flower-like NiO-NiS heterojunction was successfully employed as an efficient sulfur host for Li-S batteries. The semi-lattice-matched structure formed by NiO-NiS accelerated charge transfer and created numerous additional catalytic active sites. With these advantages, the prepared NiO-NiS/S cathode demonstrated outstanding electrochemical performance. • Semi-lattice-matched heterointerface design enhances polysulfide redox kinetics in Li-S batteries. • Nanoflower NiO-NiS synergizes NiO's rapid polysulfides adsorption with NiS's catalytic conversion. • Optimized NiO-NiS cell maintains 2C cycling stability with minimal capacity decay. • High sulfur-loading cathode (86 wt%) achieves durable performance via dual-phase interface engineering.