Hierarchical MoS2 anchored on core-shell Si@C with increased active-sites and charge transfer for superior cycling and rate capability in lithium-ion batteries

Abstract

Size-controlling and in situ hybridization of two or more active materials have been considered as promising strategies to accommodate the volume variation and enhance the conductivity of silicon, resulting in excellent electrochemical performance in lithium-ion batteries (LIBs). Herein, sandwich-like Si@C@MoS2 composite containing core-shell Si@C with interconnected MoS2 nanosheets decorated on was fabricated by molten salt magnesiothermic reduction, resorcinol formaldehyde (RF) coating and hydrothermal process. Moreover, to optimize the electrochemical properties, Si@C@MoS2 composite with different contents of MoS2 were also studied. Especially, Si@C@MoS2-0.1 composite exhibits a reversible capacity of 1365.7 mAh g−1 at 0.5 A g−1 after 500 cycles, accompanying by a high initial coulombic efficiency of 81.5%, and superior rate capability of ∼872.4 mAh g−1 at 10.0 A g−1. Moreover, the full cell that assembled by the pretreated Si@C@MoS2-0.1 electrode as anode and commercial LiCoO2 as cathode also delivers outstanding cycling performance. The ration design of constructing composite with multicomponent cannot only be applied in Si-based materials but also in other alloy-type anode materials.