Large-scale fabricating carbon coating Chevrel phase in molten salts: Implications for high-performance magnesium-ion battery cathode

Abstract

Molten salt synthesis is a facile, extensible and effective way to obtain specific electrode materials with in situ carbon coating. Herein, a carbon coating Mo6S8 compounds were synthesized based on molten KCl medium, and the excellent electrochemical Mg-storage performance were demonstrated in rechargeable Mg ion batteries. Benefiting from the in situ carbon coating, the as-synthesized Mo6S8 @C delivers a high reversible capacity of 90 mAh g–1 and a superior rate performance. Further mechanism investigation via kinetics testing, ex situ XRD and XPS demonstrate that the carbon coating layer on the surface of Mo6S8 could accelerate the electron/ion transport and improve the rate performance and stability of the electrodes. This work provides a possible way to large-scale fabrication of the carbon coating Mo6S8 and lays a foundation for the practical applications of Mg ion batteries.