Metal selenides are considered as a group of promising candidates as the anode material for sodium-ion batteries due to their high theoretical capacity. However, the intrinsically low electrical and ionic conductivities as well as huge volume change during the charge-discharge process give rise to an inferior sodium storage capability, which severely hinders their practical application. Herein, we fabricated In2Se3/CoSe2 hollow nanorods composed of In2Se3/​CoIn2/​CoSe2 by growing cobalt-based zeolitic imidazolate framework ZIF-67 on the surface of indium-based metal–organic framework MIL-68, followed by in situ gaseous selenization. Because of the CoIn2 alloy phase in between In2Se3 and CoSe2, a heterostructure consisting of two alloy/selenide interfaces has been successfully constructed, offering synergistically enhanced electrical conductivity, Na diffusion process, and structural stability, in comparison to the single CoIn2-free interface with only two metal selenides. As expected, this nanoconstruction delivers a high reversible capacity of 297.5 and 205.5 mAh g–1 at 5 and 10 A g–1 after 2000 cycles, respectively, and a superior rate performance of 371.6 mAh g–1 at even 20 A g–1.

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Tin‐based compounds have received much attention as anode materials for lithium/sodium ion batteries owing to their high theoretical capacity. However, the huge volume change usually leads to the pulverization of electrode, giving rise to a poor cycle performance, which have severely hampered their practical application. Herein, highly durable yolk–shell SnSe2 nanospheres (SnSe2@SeC) are prepared by a multistep templating method, with an in situ gas‐phase selenization of the SnO2@C hollow nanospheres. During this process, Se can be doped into the carbon shell with a tunable amount and form SeC bonds. Density functional theory calculation results reveal that the SeC bonding can enhance the charge transfer properties as well as the binding interaction between the SnSe2 core and the carbon shell, favoring an improved rate performance and a superior cyclability. As expected, the sample delivers reversible capacities of 441 and 406 mAh g−1 after 2000 cycles at 2 and 5 A g−1, respectively, as the anode material for a sodium‐ion battery. Such performances are significantly better than the control sample without the SeC bonding and also other metal selenide‐based anodes, evidently showing the advantage of Se doping in the carbon shell.

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