Flash\nJoule Heating Synthesis of Layer-Stacked Vanadium\nOxide/Graphene Hybrids within Seconds for High-Performance Aqueous\nZinc-Ion Batteries

Vanadium\noxides have been regarded as highly promising cathodes\nfor aqueous zinc-ion batteries (ZIBs). However, obtaining high-performance\nvanadium oxide-based cathodes suitable for industrial application\nremains a significant challenge due to the need for cost-effective,\nstraightforward, and efficient preparation methods. Herein, we present\na facile and rapid synthesis of a composite cathode, consisting of\nlayer-stacked VO<sub>2</sub>/V<sub>2</sub>O<sub>5</sub> and graphene-like\ncarbon nanosheets, in just 2.5 s by treating the commercial V<sub>2</sub>O<sub>5</sub> powder via a flash Joule heating strategy. When\nemployed as the cathode for ZIBs, the resulting composite delivers\na comparable rate capacity of 459 mA h g<sup>–1</sup> at 0.2\nA g<sup>–1</sup> and remarkable cycle stabilities of 355.5\nmA h g<sup>–1</sup> after 2500 cycles at 1.0 A g<sup>–1</sup> and 169.5 mA h g<sup>–1</sup> after 10,000 cycles at 10 A\ng<sup>–1</sup>, respectively. Further electrochemical analysis\nreveals that the impressive performance is attributed to the accelerated\ncharge transfer and the alleviated structure degradation, facilitated\nby the abundant sites and a built-in electric field of the layer-stacked\nVO<sub>2</sub>/V<sub>2</sub>O<sub>5</sub> heterostructure, as well\nas the excellent conductivity of graphene-like carbon nanosheets.\nThis work introduces a unique approach for ultrafast and low-cost\nfabrication of high-performance vanadium oxide-based composite cathodes\ntoward efficient ZIBs.