A new thiol-sulfur click chemistry for lithium-organosulfide batteries.

Abstract

Click chemistry is a rapid, reliable, and powerful function and a highly selective organic reaction that facilitates the efficient synthesis of various molecules by joining small units. This approach has found widespread applications in fields such as drug development, chemical synthesis, and molecular biology. In recent years, the reaction of alkali-catalyzed polymerization of thiol and sulfur has been employed to prepare various sulfur-containing polymers, which are applied as electrochemical active electrode materials in the pursuit of good performance. In this study, it is surprising to find that the reaction mechanism exhibits characteristics of both the alkali-catalyzed sulfhydryl Micheal addition reaction and thiol-epoxy click chemistry; for the first time, thiol-sulfur click chemistry is defined in detail, providing a comprehensive description of its underlying scientific principles. The introduction of this new reaction pathway holds significant potential for advancing research and the development of sulfur-containing polymers. Based on this novel click chemistry, a new sulfur-containing polymer, polydivinylthioether hexasulfide, has been designed and successfully applied as a cathode material in lithium-organosulfide batteries. This material demonstrates excellent electrochemical performance, achieving an initial capacity that reaches 790.5 mAh g^-1 (82.6% of theoretical capacity), and in a long-term cycle test, the capacity decay rate is only 0.063% after 1,000 cycles.