VS4/MoS2 cathodes with long cycle life and high rate performance for hybrid magnesium-lithium batteries

Hybrid magnesium-lithium batteries (MLIBs) have become the focus of research due to the advantages of combining a magnesium metal anode (free dendrite) and Li-driven reaction cathode (fast ion diffusion rate). VS 4 with large interchain space can be used as a potential cathode for MLIBs, but its low conductivity and weak structural stability limit the development of MLIBs. In this work, MoS 2 was introduced into VS 4 to induce the generation of abundant sulfur vacancies , which improved the structural stability and Li + ion transport properties of VS 4 . The VS 4 /MoS 2 cathode retains stability and an impressively high reversible capacity of 581.7 mAh·g −1 after 100 cycles, corresponding to a capacity retention of 98.99 % (compared with the second cycle). Meanwhile VS 4 /MoS 2 still has 472.64 mAh·g −1 at high current density of 1500 mA·g −1 , which is much higher than that of NF-VS 4 (11.9 mAh·g −1 ) and VF-VS 4 (29.8 mAh·g −1 ). This work points the way to ameliorate Mg-based rechargeable batteries.