Molybdenum disulfide (MoS 2 ) has been considered to be a promising anode material for sodium ion batteries (SIBs), because of its high capacity and graphene-like layered structure. However, irreversible conversion reaction during the sodiation/desodiation process is a major problem that must be overcome before its practical applications. In this work, MoS 2 /amorphous carbon (C) microtubes (MTs) composed of heterostructured MoS 2 /C nanosheets have been developed via a simple template method. The existence of MoS 2 /C heterointerface plays a key role in achieving high and stable performance by stabilizing the reaction products Mo and sulfide phases, providing fast electronic and Na + ions diffusion mobility, and alleviating the volume change. MoS 2 /C MTs exhibit a high reversible specific capacity of 563.5 mA h g −1 at 0.2 A g −1 , good rate performance (520.5, 489.4, 452.9, 425.1, and 401.3 mA h g −1 at 0.5, 1.0, 2.0, 5.0, and 10.0 A g −1 , respectively), and excellent cycling stability (484.9 mA h g −1 at 2.0 A g −1 after 1500 cycles).

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Sodium-ion batteries (SIBs) have been regarded as a promising alternative to lithium-ion batteries due to the natural abundance of sodium in the earth's crust. In our work, fusiform Fe 7 X 8 @C (X = S, Se) composites were obtained via a one-step pyrolysis strategy applied to SIB anode materials. The formed carbon skeleton could prevent the Fe 7 X 8 nanoparticles from agglomeration and stabilize the interface of Fe/Na 2 X generated in the redox reactions. Fe 7 X 8 @C (X = S, Se) exhibits excellent reversible specific capacity (1005.3 mAh g −1 under 0.2 A g −1 for Fe 7 S 8 @C and 458.5 mAh g −1 under 0.5 A g −1 for Fe 7 Se 8 @C), outstanding rate performance (654.7 mAh g −1 for Fe 7 S 8 @C and 392.9 mAh g −1 for Fe 7 Se 8 @C going through 300 loops even under 2 A g −1 ), and excellent cycling properties (795.8 mAh g −1 after 50 loops under 0.2 A g −1 for Fe7S 8 @C and 399.9 mAh g −1 going through 150 loops under 0.5 A g −1 for Fe 7 Se 8 @C). The excellent electrochemical performance of Fe 7 X 8 @C composites makes them promising anode materials for SIBs.