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The design of nanoscale composites with a hierarchical structure can improve the poor cycling performances of transition metal sulfides such as anode materials. The hierarchical MoS2/α-MnS nanocomposites were synthesized by a facile one-pot hydrothermal method in this study, aiming to improve the cycling performance. As an anode material, hierarchical MoS2/α-MnS nanocomposites deliver a high reversible capacity, of 1498 mAh g−1 at a current density of 50 mA g−1; a capacity of ~800 mAh g−1 is maintained over 100 cycles at 300 mA g−1, and a capacity of 907 mAh g−1 is obtained at 1200 mA g−1. Moreover, these capacities increase with the number of cycles, which is mainly owed to the occurring metallic nanoparticles that catalyze the developing polymeric film and enhance the conductivity of the active materials during the electrochemical reactions. The good cycling performances are attributed to the synergistic effects between MoS2 and α-MnS. [ABSTRACT FROM AUTHOR]

Si is a promising material for applications as a high-capacity anode material of lithium-ion batteries. However, volume expansion, poor electrical conductivity, and a short cycle life during the charging/discharging process limit the commercial use. In this paper, new ternary composites of sea urchin-like Si@MnO2@reduced graphene oxide (rGO) prepared by a simple, low-cost chemical method are presented. These can effectively reduce the volume change of Si, extend the cycle life, and increase the lithium-ion battery capacity due to the dual protection of MnO2 and rGO. The sea urchin-like Si@MnO2@rGO anode shows a discharge specific capacity of 1282.72 mAh g−1 under a test current of 1 A g−1 after 1000 cycles and excellent chemical performance at different current densities. Moreover, the volume expansion of sea urchin-like Si@MnO2@rGO anode material is ~50% after 150 cycles, which is much less than the volume expansion of Si (300%). This anode material is economical and environmentally friendly and this work made efforts to develop efficient methods to store clean energy and achieve carbon neutrality. [ABSTRACT FROM AUTHOR]