Aqueous zinc-ion batteries (ZIBs) have advantages of nontoxicity and low cost, but the Zn2+ storage mechanism still requires further investigation, giving rise to difficulty in designing a reasonable structure to improve battery performance. Here, K+-inserted layered vanadium oxide (K0.54V2O5) with a nanorod shape is demonstrated as a promising cathode material for ZIBs, and the storage mechanism of zinc ions is explored. This material displays an excellent electrochemical performance, with a capacity of 176 mA h g–1 over 2400 cycles at 5 A g–1, corresponding to a capacity retention of 97%. The attractive performance is due to the layered structure and ions embedded, which improve the gallery spacing and ion diffusion rate. More importantly, this study advances the development of vanadium-based oxides for ZIBs.

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SnSe nanorods with a length of about 1−2 μm and a width of 100 nm are achieved with the assistance of a metal complex. The growth mechanism and how metal complexes influence the morphology of SnSe are investigated. As a lithiumion-battery (LIB) anode, the nanorod structure of SnSe not only provides a fast electron/ion transmission path but also relieves the volume expansion because of the inherent mechanical strength of the one-dimensional structure. The phase change of SnSe is evaluated by ex situ X-ray diffraction during lithium insertion/ extraction to study the lithium-ion storage mechanism. Compared with SnSe nanoparticles, SnSe nanorods exhibit a better electrochemical performance, delivering an initial reversible specific capacity of 683.6 mAh g −1 at 100 mA g −1 and maintaining a specific capacity of 302 mAh g −1 even after 100 cycles, which demonstrates a promising anode material for LIBs.

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