A Review of Advances in Heterostructured Catalysts for Li–S Batteries: Structural Design and Mechanism Analysis

Lithium-sulfur (Li-S) batteries, acclaimed for their high energy density, cost-effectiveness, and environmental benefits, are widely considered as a leading candidate for the next-generation energy storage systems. However, their commercialization is impeded by critical challenges, such as the shuttle effect of lithium polysulfides and sluggish reaction kinetics. These issues can be effectively mitigated through the design of heterojunction catalysts. Despite the remarkable advancements in this field, a comprehensive elucidation of the underlying mechanisms and structure-performance relationships of heterojunction catalysts in sulfur electrocatalysis systems remains conspicuously absent. Here, it is expounded upon the mechanisms underlying heterostructure engineering in Li-S batteries and the latest advancements in heterostructure catalysts guided by these multifarious mechanisms are examined. Furthermore, it illuminates groundbreaking paradigms in heterostructure design, encompassing the realms of composition, structure, function, and application. Finally, the research trends and future development directions for the novel heterojunction materials are extensively deliberated. This study not only provides a comprehensive and profound understanding of heterostructure catalysts in Li-S batteries but also facilitates the exploration of new electrocatalyst systems.