Electronic Structure Modulation of NiCo2S4 Hollow Dodecahedrons by In Situ Compositing MoS2 for Boosted Reaction Kinetics in Li-O2 Batteries.

Rechargeable Li-O2 batteries have attracted significant attention as a next-generation energy storage technology because of their extremely high theoretical energy density. However, practical implementation remains hindered by limited energy density, poor cycling stability, pronounced parasitic reactions, and elevated overpotentials. Using zeolitic imidazolate frameworks (ZIFs) as templates, MoS2@NiCo2S4 heterostructures were formed in situ via conversion to bimetallic layered double hydroxides, and the resulting hollow architecture was assembled from MoS2 and NiCo2S4 nanosheets. MoS2@NiCo2S4 cathodes deliver remarkable discharge/charge specific capacities of 12412/11453 mAh g-1 at 100 mA g-1 and enhanced cycling stability over 208 cycles at 500 mA g-1 in Li-O2 batteries. The improved performance of MoS2@NiCo2S4 is mainly due to strong interactions between these two phases, with a hollow, porous structure that enhances regulation of reaction intermediates and enables precise control over electrochemical pathways during charging and discharging. Specifically, uniform formation and efficient decomposition of conformal Li2O2 films were facilitated, and detrimental issues were effectively eased, resulting in improved reaction kinetics, enhanced capacity retention, and extended cycling stability. These findings highlight the great potential of MoS2@NiCo2S4 heterostructures for applying in research fields of advanced energy storage and conversion, presenting a promising strategy for next-generation energy technologies.