MoO2-loaded porous carbon hollow spheres as anode materials for lithium-ion batteries

In this study, novel MoO 2 -loaded porous carbon hollow sphere composite materials were synthesized. The composites consisted of homogeneous hollow microspheres with a size of ∼0.7 ± 0.1 μm and a shell thickness of ∼70 nm; MoO 2 nanoparticles with an average size of ∼12 nm were uniformly dispersed in the shells of the porous carbon hollow spheres (PCHS). The MoO 2 /PCHS composites showed high capacity and excellent capacity retention when they were applied as an anode material for Li ion batteries . The composite containing 44.2% of MoO 2 revealed a reversible capacity of 574 mAh g −1 at a current density of 50 mA g −1 , and a first coulombic efficiency of 61%. After 80 cycles, this composite still retained a capacity of 640 mAh g −1 . The good electrochemical performance could be due to the fact that the MoO 2 nanoparticles were homogeneously embedded in the shells of the porous carbon hollow spheres in the composites, which effectively prevented volume change or aggregation of the MoO 2 nanoparticles during the lithium ion insertion/extraction process. The porous carbon hollow spheres with good electronic conductivity and high surface area offered a large electrode/electrolyte contact area, and a short path length for the Li + transport.