SiOx/C-Decorated CoO Nanosheets as a Long-life Anode for Lithium-Ion Batteries

Graphical In the mill : Unique hierarchical mosaic-structure SiO x /C@CoO nanosheets, with both SiO x and graphite particles embedded in a CoO layered structure, are successfully fabricated through a high-energy ball-milling process and through a one-step hydrothermal process to form a 3D hierarchical mosaic structure. The unique combination of the CoO and SiO x /C can accommodate the large volume changes and retain the structural integrity of the nanosheets, maintaining the cycling stability and rate capability of SiOx/C@CoO electrode materials. Unique hierarchical mosaic-structure SiO x /C@CoO nanosheets were successfully synthesized from SiO x /C nanospheres embedded in CoO nanosheets through a high-energy ball milling and hydrothermal self-assembly process. The SiO x /C@CoO material exhibited good cyclic performance with a reversible discharge capacity of 1079 mAh g −1 over 250 cycles at a current density of 1000 mA g −1 . It also displayed an excellent rate capability (with an average specific reversible discharge capacity of 777.8 mAh g −1 at 2000 mA g −1 and 480 mAh g −1 at 5000 mA g −1 ). The stable skeleton structure of SiO x /C-embedded CoO nanosheets and the synergistic effect between the two materials should be responsible for the improvement of the lithium storage. This work proposes a feasible approach to promote CoO application in lithium-ion batteries.