Three birds with one arrow: Multifunctional single-atom catalysts enable efficient lithium-sulfur batteries

The lithium-sulfur battery (LSB) has garnered considerable attention as prospective energy storage solution due to its outstanding theoretical energy density. However, the actual performance of LSBs falls short of meeting expectations, despite utilizing porous and highly conductive sulfur hosts to enhance their electrical conductivity and accommodate volume fluctuations. The primary factor contributing to the restricted performance is ascribed to the sluggish transformation of lithium polysulfides (LiPS) into sulfur and lithium sulfides. Single-atom catalysts (SACs) with outstanding activities and minimized weight offer an effective strategy to overcome this limitation. This work provides a comprehensive overview of the latest advancements in the field of SACS for LSBs, encompassing various aspects such as catalyst synthesis methods, battery performance evaluation, and mechanistic elucidation. The incorporation of SACs in the cathodes and separators facilitates the absorption of LiPS and enhances their conversion kinetics, thereby mitigating the adverse shuttle effect. In addition, SACs have a significant function at the anode by aiding the lithium stripping/plating process and concurrently preventing the development and enlargement of lithium dendrites. Overall, the design, engineering, and incorporation of SACs in LSBs and the understanding of their role are topics that deserve additional attention as a highly suitable strategy to boost LSB performance.