Insights into the storage mechanism of VS4 nanowire clusters in aluminum-ion battery

Abstract As promising electrode materials for aluminum-ion batteries (AIBs), transition metal sulfides have attracted significant attention. However, the relative low energy density and poor rate property restrict their further applications. Herein, channels-rich VS4 nanowire clusters were synthesized via an amine ions-assisted method. When assessed as a cathode for rechargeable AIB, the VS4 nanowire clusters exhibit superior electrochemical performances, specifically, outstanding rate property (103.32 mAh g-1 at 800 mA g-1), good cycling stability and a high reversible capacity of 252.51 mAh g-1 (at 100 mA g-1). Moreover, ex-situ X-ray diffraction (XRD) and in-situ Raman techniques reveal that the as-prepared VS4 nanowire clusters have stable channels-rich structures, which is favorable for the mass transfer in electrochemical reaction. A mechanism of intercalation is proposed for the electrochemical process. This work takes a step toward the development of high-performance electrode materials for AIBs and provides new insights into the chemistry of AIBs for electrochemical energy storage.