Anchoring hollow MoO2 spheres on graphene for superior lithium storage

Hollow MoO2 spheres anchored on nitrogen-doped graphene (H-MoO2@rGO) are synthesized with an in situ selfassembly approach. The hollow structure could provide sufficient space to accommodate the volume variation of MoO2 during the discharge-charge process, thus improving the cycling stability. Nitrogen-doped graphene can accelerate the charge transfer. Moreover, the graphene and MoO2 are proved to be strongly connected through C-O-Mo linkage, which provide good pathways for charge transfer and thus allowing an improved rate capability. Benefiting from the above features, H-MoO2@rGO delivers impressive cycling stability with a capacity of 414 mAh g(-1) after 1000 cycles at 2 C. Even at a high discharge/charge rate of 5 C, the composite still could deliver a capacity of 478 mAh g-1.