Insight into Lithium–sulfur batteries performance enhancement: from metal nanoparticles to metal nanoclusters to single metal atoms

Lithium–sulfur (Li–S) batteries have attracted much attention and developed rapidly in recent years due to their high energy density, low cost, and environment-friendly. However, its commercialization process still encounters various obstacles. Among them, the sulfur cathode is easy to dissolve and shuttle, resulting in the loss of active substances and the severe growth of lithium anode dendrites, which is one of the biggest obstacles. Improving the redox conversion kinetics of sulfur cathode is expected to fundamentally alleviate the shuttle phenomenon of polysulfides. Therefore, this paper reviews the effects of metal nanoparticles to metal nanoclusters to metal single-atom catalysts on improving the redox of Li–S batteries, to let researchers better understand the size effect on the kinetics of sulfur cathodes in Li–S batteries, which will provide important guidance for the future large-scale commercialization of Li–S batteries.