In the present work, the nanocomposite ZnV 2 O 4 -CMK was synthesized for the first time by using a low temperature carbothermal reduction route and was then characterized by means of X-ray diffraction (XRD), thermogravimetric analysis (TG), N 2 adsorption-desorption, scanning and transmission electron microscopy (SEM/TEM). Furthermore, the nanocomposite was used for the first time as an anode material for Li-ion intercalation and exhibited a large reversible capacity, high rate performance and cycling stability. A reversible capacity of 575 mA h g À1 was maintained even after 200 cycles at a current density of 0.1 A g À1 . These results might be due to the intrinsic characteristics of the nanocomposite offering a large surface area providing more sites for Li-ion insertion and a shorter path for Li-ion and electron transport, leading to improved capacity and enhanced rate capability.

Ultrathin Li 4 Ti 5 O 12 (LTO) nanosheets were successfully synthesized for the first time using the ultrathin titanate nanowires as a precursor. The synthesized Li 4 Ti 5 O 12 nanosheets have a large surface area of 159.2m2g-1 and their thickness was found to be ca. 5–7 nm. These nanosheets were highly crystalline and used as anode materials in rechargeable lithium-ion batteries. A stable capacity of 150 mAhg-1 for LTO nanosheets can be retained after 70 cycles at a current density of 1 Ag-1 in the voltage window of 2.5–1.0 V. It is notable that a large capacity of 267.5 mAhg-1 was obtained at the second discharge and 166 mAhg-1 can be retained after 70 cycles at 1 Ag-1 in the voltage range of 2.5–0.02 V. These results indicate that the anode materials made of spinel LTO nanosheets displayed a large reversible capacity at a high charge/discharge rate.

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Developing electrodes with long lifespan and wide‐temperature adaptability is crucial important to achieve high‐performance sodium/potassium‐ion batteries (SIBs/PIBs). Herein, the SnSe2‐SePAN composite was fabricated for extraordinarily stable and wide‐temperature range SIBs/PIBs through a coupling strategy between controllable electrospinning and selenylation, in which SnSe2 nanoparticles were uniformly encapsulated in the SePAN matrix. The unique structure of SnSe2‐SePAN not only relieves drastic volume variation but also guarantees the structural integrity of the composite, endowing SnSe2‐SePAN with excellent sodium/potassium storage properties. Consequently, SnSe2‐SePAN displays a high sodium storage capacity and excellent feasibility in a wide working temperature range (−15 to 60°C: 300 mAh g−1/700 cycles/−15°C; 352 mAh g−1/100 cycles/60°C at 0.5 A g−1). At room temperature, it delivers a record‐ultralong cycling life of 192 mAh g−1 that exceeds 66 000 cycles even at 15 A g−1. It exhibits extremely superb electrochemical performance in PIBs (157 mAh g−1 exceeding 15 000 cycles at 5 A g−1). The ex situ XRD and TEM results attest the conversion‐alloy mechanism of SnSe2‐SePAN. Also, computational calculations verify that SePAN takes an important role in intensifying the electrochemical performance of SnSe2‐SePAN electrode. Therefore, this study breaks new ground on solving the polyselenide dissolution issue and improving the wide temperature workable performance of sodium/potassium storage.