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Binary metal sulfides CoS@SnS nanoparticles confined in N -doped carbon microsphere have been reasonably fabricated, which exhibits excellent electrochemical performance when evaluated as an anode material for half/full sodium-ion batteries. [Display omitted] The development of high-capacity anode materials is crucial for sodium-ion batteries. Alloy-type anode materials have attracted tremendous attention due to their high theoretical capacities. Nonetheless, the realizations of high capacity and remarkable cycling stability are actually hindered by the sluggish reaction kinetics of sodium storage. Here, we report a binary metal sulfides CoS@SnS heterostructure confined in carbon microspheres (denoted as (CoSn)S/C) through a facile hydrothermal reaction combined with annealing treatment. The (CoSn)S/C with micro/nanostructure can shorten ion diffusion length and increase mechanical strength of electrode. Besides, the heterogeneous interface between CoS and SnS can improve the inherent conductivity and favor the rapid transfer of Na+. Benefitting from these advantages, (CoSn)S/C composite exhibits a high reversible capacity of 463 mAh g−1 and superior durability (368 mAh g−1 at 2 A g−1 after 1000 cycles). Notably, the assembled Na 3 V 2 (PO 4) 3 //(CoSn)S/C full cell delivers a reversible capacity of 386 mAh g−1 at 0.2 A g−1, proving that the (CoSn)S/C is a promising anode material for sodium-ion batteries. The density functional theory (DFT) calculations unveil the mechanism and significance of the constructed CoS@SnS heterostructure for the sodium storage at atomic level. This work provides an important reference for in-depth understanding of reaction kinetics of bimetallic sulfides heterostructure. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work provides a novel and reliable insight for designing bimetallic sulfide with 2D nanostructure. • Laurel-leaf-like Co 9 S 8 /WS 2 @NC delivers a capacity of 359 mA h g−1 at 5.0 A g−1 • This as-prepared bimetallic sulfide exhibits a high capacitive contribution ratio of 90.8%. • The excellent performance originates from interface electric field and synergistic effects Co 9 S 8 and WS 2. Devising novel composite electrodes with particular structural/electrochemical characteristics becomes an efficient strategy to advance the performance of rechargeable battery. Herein, considering the homogeneous transition metal sulfide with N-doped carbon derived from zeolitic imidazolate framework-67 (ZIF-67) and WS 2 with large interlayer spacing, a laurel-leaf-like Co 9 S 8 /WS 2 @N-doped carbon bimetallic sulfide (Co 9 S 8 /WS 2 @NC) is engineered and prepared via a step-by-step method. As an electrode material for sodium ion batteries (SIBs), Co 9 S 8 /WS 2 @NC composite delivers high capacities of 480 and 405 mA h g−1 at 0.1 and 1.0 A g−1, respectively. As the current density increases from 0.1 to 5.0 A g−1, it provides specific capacity of 359 mA h g−1 with a capacity retention rate of 78.0%, which is higher than that of Co 9 S 8 @NC (63.5%) and WS 2 (58.6%). The Co 9 S 8 /WS 2 @NC composite anode maintains a stable specific capacity (354 mA h g−1 at 2.0 A g−1). It also exhibits a high capacitive contribution ratio of 90.8% at 1.0 mV s−1. This study provides a new and reliable insight for designing bimetallic sulfide with two-dimensional nanostructure for energy storage. [ABSTRACT FROM AUTHOR]