Rational engineering of VS₄ nanorod array on rose-shaped VS₂ nanosheets for high-performance aluminium-ion batteries

High performance aluminium-ion (Al-ion) batteries are of wide interest owing to the high theoretical capacity, abundance of Al metal and good safety. Here, we develop a hierarchical VS₂@VS₄ composed of a VS₄ nanorod array in situ grown on VS₂ rose-shaped nanosheets that displays a good electrochemical performance. The VS₂@VS₄ cathode displays a high capacity of 162.7 mA h g^-1 after 200 cycles at -10 °C, and keeps 116.5 mA h g^-1 after 500 cycles at room temperature. Rate-performance at -10 °C shows a capacity retention rate of 90%, which indicates the potential for engineering high-performance energy-storage composites.