Atomic Insights into the S Poisoning Effects of Single-Atom Catalysts in Li–S Batteries
Chang Li, Haibo Luo, Fengyu Li, Fen Li
Abstract
High Resolution Image Download MS PowerPoint Slide Here, we paved a new way to evaluate the susceptibility of M–N 4 -based single-atom catalysts (SACs) to sulfur poisoning in Li–S batteries. The strong binding strength of M–S in Ti–N 4 - and V–N 4 -based SACs is attributed to the high bond order, pronounced d–p hybridization, and differential charge density. However, overly strong binding strength of M–S can create a high energy barrier that prevents the detachment of covered S atoms and induces sulfur poisoning. This can significantly impede the exposure of catalysts to residual reactants during subsequent charge–discharge cycles. Moreover, the sulfur poisoning will dramatically depress the overall catalytic performance of the SACs during the subsequent charge–discharge process, indicating that some compromise should be made between the high catalytic performance and the sulfur poisoning in designing SACs for Li–S batteries.