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Metal sulfides are considered as promising anodes for lithium-ion batteries (LIBs) because of their high capacity. Among all of these metal sulfides, Tin(II) sulfide (SnS), possessing a unique 2D structure and with high lithium storage capacity, attract more attention as a promising anode for LIBs. However, serious volume change, sluggish kinetics, and low electric conductivity during the charging/discharging process, lead to poor rate capability and fast capacity fading. Herein, a ZnS/SnS@C yolk-shell microspheres (ZSS@NC) is synthesized through a facile hydrothermal process coupled with a PPy coating and sulfidation-in-microsphere strategy. The built-in electric field generated from ZnS/SnS heterostructure benefits the rapid transport of Li-ion and enhances the electric conductivity. Meanwhile, the N-doped carbon further improves the electronic conductivity and provides a robust support architecture, which can mitigate the volume variation of ZnS/SnS during the lithiation/delithiation process. Therefore, the ZnS/SnS@NC delivers high capacity (775.5 mA h g−1 at 200 mA g−1 after 200 cycles), outstanding rate performance (395.8 mA h g−1 at 5 A g−1), and superior long-term cycling performance (571.2 mA h g−1 at 1 A g−1 after 1000 cycles). • ZnS/SnS@C microspheres are synthesized through a facile hydrothermal process coupled with a PPy coating. • The built-in electric field generated from ZnS/SnS heterostructure benefits the rapid transport of Li-ion. • The N-doped carbon can improve the electronic conductivity and mitigate the volume variation. • The ZnS/SnS@NC composite presents long-life cycle performance and superior rate capability. [ABSTRACT FROM AUTHOR]

MnS is considered as a potential anode own to its merits of high specific capacity, suitable voltage potential, and unique α→β phase transition reaction. Nevertheless, its intrinsic low conductivity, volume variation, and polysulfide dissolution during the lithiation/delithiation process, resulting in inferior cycling performance, then limit its practical application for LIBs. Herein, a novel anode material composited of Mn-Sn bimetallic sulfides heterostructure and N-doped carbon shell (MnS/SnS@NC) is designed. In such a designed MnS/SnS@NC composite, the N-doped carbon is tightly wrapped in the inner MnS/SnS heterostructure through the C-S-Mn bond, which is beneficial to keep the structural stability and enhance the electrochemical reaction kinetics during the lithiation/delithiation process. Furthermore, the heterostructure boosts the ion and electron transfer, and the N-doped carbon buffers the volume change during the cycling process. As a result, the MnS/SnS@NC delivers an excellent long-cycle performance (719.6 mAh g−1 at 1.0 A g−1 after 1000 cycles) and an outstanding rate performance (416.6 mAh g−1 at 5 A g−1). [Display omitted] • A novel heterostructure composited of Mn-Sn bimetallic sulfides was synthesized. • The carbon coating method was dopted via a simple metal chelate-assisted method. • The heterojunctions and N-doped carbon layer co-construct an advanced LIBs anode material. • The MnS/SnS@NC composite exhibits stable cycle performance and superior rate capability. [ABSTRACT FROM AUTHOR]