材料期刊网

Transition-metal oxides have attracted increased attention in the application of high-performance lithium ion batteries (LIBs),owing to its higher reversible capacity,better structural stability and high electronic conductivity.Herein,CoWO4 nanoparticles wrapped by reduced graphene oxide (CoWO4-RGO) were synthesized via a facile hydrothermal route followed by a subsequent heat-treatment process.When evaluated as the anode of LIB,the synthetic CoWO4-RGO nanocomposite exhibits better Li+ storage properties than pure CoWO4 nanostructures synthesized without graphene oxide (GO).Specifically,it delivers a high initial specific discharge capacity of 1100 mAh.g-1 at a current density of 100 mA.g-1,and a good reversible performance of 567 mAh.g-1 remains after the 100th cycle.Moreover,full battery using CoWO4RGO as anode and commercial LiCoO2 powder as cathode was assembled,which can be sufficient to turn on a 3 V,10 mW blue light emitting diode (LED).The enhanced electrochemical performance for lithium storage can be attributed to the three-dimensional (3D) structure of the CoWO4-RGO nanocomposite,which can accommodate huge volume changes,and synergetic effect between CoWO4 and reduced graphite oxide (RGO) nanosheets,including an increased conductivity,shortened Li+ diffusion path.