Rational engineering of VS 4 nanorod array on rose-shaped VS 2 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 VS 2 @VS 4 composed of a VS 4 nanorod array in situ grown on VS 2 rose-shaped nanosheets that displays a good electrochemical performance. The VS 2 @VS 4 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.