Layered BaV 6 O 16 ·3H 2 O@GO as a high performance cathode material for calcium ion batteries.

The lack of suitable cathode materials has hampered the further development of calcium-ion batteries (CIBs). A novel composite cathode material, namely BaV 6 O 16 ·3H 2 O@GO, was fabricated, which delivers a high specific capacity of 285.72 mA h g -1 at 50 mA g -1 after 50 cycles and a long cycle life, benefiting from a large layer spacing and robust structure. This study provides guidance for the development of vanadium-based cathode materials for CIBs.