Interfacial reinforcement structure design towards ultrastable lithium storage in MoS₂-based composited electrode

Huge volume expansion and inferior electrical conductivity are the two main obstacles to limit the practical applications of high-capacity molybdenum disulfide (MoS₂) materials, which has been recognized as ideal anode materials for rechargeable lithium-ion batteries. Herein, an interfacial reinforcement structure design is proposed by conformally growing few-layered MoS₂ nanosheets on carbon coated ultralong TiO₂ nanotubes (TiO₂@C@MoS₂) to stabilize the solid electrolyte interface (SEI) of MoS₂-based electrode. The interlayer carbon coating on TiO₂ nanotubes effectively improves the interfacial contact between MoS₂ nanosheets and TiO₂ nanotubes by forming Ti-O-C and C-S chemical bonds between TiO₂/carbon coating and MoS₂/carbon coating, respectively, avoiding MoS₂ nanosheets detaching from TiO₂ nanotubes. Meanwhile, the carbon coating serves as a buffering cushion to alleviate mechanical strain at the interface of MoS₂ nanosheets and TiO₂ nanotubes. Besides, it enhances the adsorption performance of Li ions on the surface of MoS₂ and at the interface sites between MoS₂ and TiO₂. While three-dimensional rigid TiO₂ nanotubes networks work as mechanical support to suppress reaggregating and restacking of MoS₂ nanosheets, and provide fast transportation expressways for electrons/ions. Thus, the TiO₂@C@MoS₂ electrode exhibits ultrafast charge/discharge capability, a high reversible capacity of 1150 mAh g⁻¹ at 0.1 A g⁻¹, and superior cycling performance with 90% capacity retention after 1500 cycles at 1.0 A g⁻¹. This interfacial reinforcement structure design provides valuable experience to benefit rational design of alloy/conversion-typed materials electrode with high-performance.