In-situ conversion method for Co9S8 embedded in N-doped carbon derived from resin waste induced ultra-stable Li-S batteries

The effective suppression of the shuttle effect in lithium-sulfur batteries require the development of efficient electrocatalysts. Transition metal sulfides show great potential as S cathode electrocatalysts. However, the conventional secondary sulfidation or heat-treatment process used in their synthesis limits their catalytic performance. In this study, we propose an efficient and scalable " exchange-constriction-in-situ conversion " strategy to prepare Co 9 S 8 @NC electrocatalysts using CoSO 4 and waste resins as sources. No additional sulfur source is required in this process. The resulting Co 9 S 8 @NC catalyst demonstrates outstanding long-cycle performance, with a slight decay of only 0.028 % per cycle after 500 cycles at a current density of 2 C. Moreover, it exhibits excellent electrochemical performance even at high surface loading and low electrolyte dosage (E/S). The combination of theoretical calculations and electrochemical analyses demonstrates that Co 9 S 8 possesses strong adsorption, superior catalytic capacity and lower energy barrier of decomposition towards lithium polysulfide, consequently leads to an enhancement in reaction kinetics. This study presents a novel approach for synthesizing high-performance sulfide electrocatalysts.