Insight into the Superior Lithium Storage Properties of Ultrafine CoO Nanoparticles Confined in a 3 D Bimodal Ordered Mesoporous Carbon CMK-9 Anode

Ultrafine CoO particles immobilized into the mesopores of three-dimensional cubic bimodal ordered mesoporous carbon CMK-9 is successfully prepared by using a combination of nanocasting and wet-impregnation methods. It is found that the cubic bimodal interconnected mesoporous framework of CMK-9 plays a crucial role in achieving the excellent electrochemical performances by assisting the rapid mass and charge transfer. Among the prepared nanocomposites, CoO(10)@CMK-9 delivers a discharge capacity of 830 mAh g^-1 after 200 cycles at a current density of 100 mA g^-1 in lithium-ion batteries. At a higher current density of 1000 mA g^-1 , the anode presents an outstanding discharge capacity of 636 mAh g^-1 after 200 cycles. In sodium-ion batteries, the anode provides a discharge capacity of 296 mAh g^-1 after 250 cycles at a current density of 100 mA g^-1 . The remarkable performances of CoO(10)@CMK-9 demonstrate the promising potentials of the nanocomposite as the anode for rechargeable batteries.