Single Atom-Based Nanoarchitectured Electrodes for High-Performance Lithium–Sulfur Batteries

Lithium−sulfur (Li−S) batteries have attracted particular interest as promising next-generation energy storage devices because of their high theoretical energy density and low cost. The real performance of Li−S batteries is, however, far from achieving the expected values, even when using a porous, highly conductive host of sulfurs to improve their electric conductivity and accommodate their volume changes. The performance restrictions are mainly attributable to the slow reaction kinetics of converting lithium polysulfides species to lithium sulfide and elemental sulfur during the charging and discharging processes, respectively. Recent studies show that single-atom catalysts (SACs) with superior catalytic activity offer an effective strategy for solving this tough issue. The recent advances in utilizing SACs for Li−S batteries, which involve catalyst preparation, battery performance, and mechanistic insights, are summarized here. Modification of the cathodes and separators with SACs helps to absorb polysulfide and promote their conversion kinetics, thus suppressing the notorious “shuttle effect.” In addition, the introduction of SACs into Li−S batteries promotes the efficiency of Li stripping/plating and prevents the growth of Li dendrites. Overall, the boost effects of SAC on Li−S batteries performance are noticeable and deserving of more research attention to develop better Li−S batteries.