Construction of highly conductive MoS2/MoO2/reduced graphene oxide nanocomposites for ultralong-life hybrid Mg2+/Li+ batteries

Hybrid Mg 2+ /Li + batteries (MLIBs) are a promising battery system that combines the advantages of fast lithium-ion kinetics and dendrite-free magnesium deposition. Layered molybdenum disulfide (MoS 2 ) has gained increasing interest due to larger layer spacing and weak van der Waals forces in MLIBs. However, poor intrinsic electronic conductivity hinders its practical application. Here, a highly conductive MoS 2 /MoO 2 /reduced graphene oxide (MoS 2 /MoO 2 /rGO) composite synthesized via a facile hydrothermal method is employed as a high-performance cathode material for MLIBs. The high electrical conductivity (7.5 ×10 −3 S cm −1 ) and large specific surface area of MoS 2 /MoO 2 /rGO facilitate the rapid transport of interfacial electrons and provide abundant active sites for Mg 2+ /Li + storage. The optimized MoS 2 /MoO 2 /rGO composite exhibits a high discharge capacity (297.3 mAh g −1 ) and excellent rate performance. Moreover, the composite electrode delivers ultra-long cycle life over 5000 cycles at 1000 mA g −1 , with a capacity degradation rate of only 0.007 % per cycle. The results offer valuable insights for the development of highly conductive MoS 2 -based composites.