Linking D‐Band Center Modulation with Rapid Reversible Sulfur Conversion Kinetics via Structural Engineering of VS₂

Abstract

The rapid catalytic conversion toward polysulfides is considered to be an advantageous approach to boost the reaction kinetics and inhibit the shuttle effect in lithium‐sulfur (Li─S) batteries. However, the prediction of high catalytic activity Li─S catalysts has become challenging given the carelessness in the relationship between important electronic characteristics of catalysts and catalytic activity. Herein, the relationships between the D‐band regulation of catalysts with reaction kinetics toward polysulfides are described. Through the combination of experimental and theoretical analysis, the opportune upward shift of the D‐band center results in a favorable interaction with polysulfides, controlling the adsorption behavior of polysulfides. In addition, the electron regulation achieved by moderately moving up the D‐band center further reduces the reaction energy barrier through hybridization with polysulfides. Based on this, a composite catalyst Mo doped VS2/rGO as a host material is proposed, which provides impressive long‐term cycling stability and superior rate performance. This fundamental knowledge of the inherent connection between the D‐band center of the catalyst and the reaction Kinetics of polysulfides offers a rationale for the development of the Li─S catalyst and the modification of its activity.