Universal‐Descriptors‐Guided Design of Single Atom Catalysts toward Oxidation of Li₂S in Lithium–Sulfur Batteries

Abstract

The sulfur redox kinetics critically matters to superior lithium-sulfur (Li-S) batteries, for which single atom catalysts (SACs) take effect on promoting Li₂ S redox process and mitigating the shuttle behavior of lithium polysulfide (LiPs). However, conventional trial-and-error strategy significantly slows down the development of SACs in Li-S batteries. Here, the Li₂ S oxidation processes over MN₄ @G catalysts are fully explored and energy barrier of Li₂ S decomposition (E_b ) is identified to correlate strongly with three parameters of energy difference between initial and final states of Li₂ S decomposition, reaction energy of Li₂ S oxidation and LiS bond strength. These three parameters can serve as efficient descriptors by which two excellent SACs of MoN₄ @G and WN₄ @G are screened which give rise to E_b values of 0.58 and 0.55 eV, respectively, outperforming other analogues in adsorbing LiPs and accelerating the redox kinetics of Li₂ S. This method can be extended to a wider range of SACs by coupling MN₄ moiety with heterostructures and heteroatoms beyond N where WN₄ @G/TiS₂ heterointerface is predicted to exhibit enhanced catalytic performance for Li₂ S decomposition with E_b of 0.40 eV. This work will help accelerate the process of designing a wider range of efficient catalysts in Li-S batteries and even beyond, e.g. alkali-ion-Chalcogen batteries.