Interface engineering of few-layered MoS2 nanosheets with ultrafine TiO2 nanoparticles for ultrastable Li-ion batteries

摘要

The highly structural integrity of electrode materials before and after cycles has been widely recognized as the pivotal for achieving stable lithium-ion batteries. Herein, an interface-reinforcement strategy has been developed to enhance the structural stability of two-dimensional (2D) nanomaterials. The TiO2/MoS2 hybrids are synthesized by anchoring ultrafine TiO2 nanoparticles on few-layered MoS2 nanosheets using a facile and scalable method. Such a fascinating 0D/2D heterostructure can effectively overcome the shortcoming of MoS2 nanosheets easy-stacking, promoting the electrolyte accessability to 2D interlayer space. Impressively, the robust Ti-O-S covalent interaction between them can greatly consolidate the 2D nanosheets, alleviating the structural stress change caused by lithiation/delithiation. Consequently, the as-obtained TiO2/MoS2 hybrids exhibit a remarkably improved specific capacity compared to the exfoliated MoS2 nanosheets at various rates. A stable specific capacity of 410 mAh g(-1) is still maintained even through over 500 cycles at 1.0 A g(-1). The interface-reinforcement concept can also be extended to other 2D nanomaterials, showing huge application potential for stable LIBs.