VO2/MoS2 heterostructure synergized oxygen vacancies as a cathode material for high-performance hybrid Mg/Li-ion batteries over a wide temperature range

Hybrid magnesium-lithium batteries (MLIBs) are a promising battery system with safety and exceptional reaction kinetics due to the combination of the dendritic-free deposition Mg metal anode and the rapid Li intercalation cathode. The large interchain frame of VO 2 may contribute to the metal-ion diffusion, making it a suitable cathode for MLIBs. However, the development of VO 2 cathodes for MLIBs is restricted by bad structural stability and low electronic conductivity. Herein, MoS 2 with a hexagonal crystal structure is introduced into the tetragonal VO 2 to construct heterostructure interfaces and induce abundant oxygen vacancies (VO 2 /MoS 2 -2), which enhances the structural stability and reaction kinetics. For this reason, the VO 2 /MoS 2 -2 cathode delivers a remarkable capacity (518 mAh g -1 ) and a considerable cycling lifespan (202 mAh g -1 at 1.0   A   g -1 over 700 cycles). Even at low temperatures (-15 and -40 °C), VO 2 /MoS 2 -2 delivers 145 and 115 mAh g -1 after 200 and 50 cycles at 0.1   A   g -1 , respectively. This strategy of combinatorial design offers a widely applicable method for the cryogenic resistance and cycling durability of magnesium-lithium batteries.