Biphasic Fe7S8@MnS heterostructure embedded in sulfur-doped carbon matrix as anode for Li-ion batteries.

• Biphasic Fe 7 S 8 @MnS heterostructure embedded in sulfur-doped carbon matrix was synthesized. • The composites exhibit enhanced lithium storage performance with high rate capability and long cycling stability. • These results can be attributed to the multiphasic components with heterostructures and porous conductive carbon frameworks. Transition metal chalcogenides have been regarded as promising anode candidates for lithium-ion batteries, featured by their high capacity and abundant material choice. However, their practical implementation was hindered by the poor reaction kinetics and rapid capacity fading due to their low electronic conductivity and severe volume variation upon the (de-)lithiation processes. Here, we have successfully fabricated the biphasic Fe 7 S 8 @MnS heterostructure embedded in sulfur-doped carbon matrix by direct sulfidation of Fe/Mn bimetal-organic frameworks. The biphasic heterostructure and the porous carbon frameworks can create abundant phase boundaries and multiple conductive channels for change transfer, thus improving the electronic conductivity and contact area with electrolyte, leading to facilitated charge transfer capability. As a result, the Fe 7 S 8 @MnS/C composites exhibit superior lithium storage performance with a specific capacity of 917 mA h g−1 at 0.1 A g−1 and maintain at 581 mA h g−1 after 500 cycles at 1 A g−1. This work provides an efficient strategy for constructing multiphase nanomaterials towards high performance anodes for Li-ion batteries. [ABSTRACT FROM AUTHOR]