Recent Advances and Strategies of Metal Sulfides for Accelerating Polysulfide Redox and Regulating Li Plating.

Metal sulfides are emerging as multifunctional mediators to address the shuttle effect and lithium dendrite growth in lithium-sulfur batteries (LSBs), yet their structure-property-catalysis relationships remain underexplored. This review critically examines the dual functionality of mono-, bi-, and multimetallic sulfides in simultaneously accelerating polysulfide redox kinetics and guiding uniform lithium deposition. By analyzing their mechanisms in sulfur cathodes and Li-metal anodes, we reveal how tailored electronic structures, interfacial engineering, and heterostructure design enhance the catalytic selectivity and cycling stability. We further evaluate synthesis strategies to balance conductivity, adsorption strength, and active site density, offering design principles for integrated sulfide-based architectures. Finally, we outline key challenges in scalability and interfacial dynamics, proposing advanced characterization and machine learning as pathways to unlock high-energy, long-cycle LSBs.