ZnO/Ni/C composite hollow microspheres as anode materials for lithium ion batteries

ZnO/Ni/C composite hollow microspheres were synthesized by calcination of zinc-nickel citrate hollow microspheres at 500 °C for 2 h in argon. The composite hollow microspheres with an average diameter of 1.2 μm are made up of numerous nanoparticles with sizes ranging from 15 to 25 nm. When applied as the anode materials for lithium ion batteries, the composite hollow microspheres demonstrate excellent cycling stability. Compared to ZnO solid microspheres, the enhanced electrochemical properties of ZnO/Ni/C composites are attributed to the decoration of nickel and carbon as well as its unique hollow structures. ZnO/NiO/C composite hollow microspheres prepared by calcination of ZnO/Ni/C composites in air also reveal good lithium storage properties.