Well-dispersed ZnFe 2 O 4 nanoparticles onto graphene as superior anode materials for lithium ion batteries

Abstract

We prepared well-dispersed ZnFe 2 O 4 (ZFO) nanoparticles on a graphene sheet by a facile one-step hydrothermal method using glucose as a novel linker agent and low-cost graphene flake. It was found that the glucose linkage on graphene not only prevented the aggregation of ZFO particles, but also induced the exfoliation of graphene flakes. The addition of glucose during the synthesis made surface linkages on the graphene surface, and it reacted with ZFO precursors, resulting in the well-dispersed ZFO nanoparticles/graphene composite. Furthermore, the size distribution of the resultant composite particles was also shifted to the smaller particle size compared to the composite prepared without glucose. The newly prepared ZFO/graphene composite provided a higher lithium storage capability and cycle performance compared to the ZFO/graphene sample which was prepared without glucose. The good dispersion of ZFO nanoparticles on graphene and the small particle size of the composite led to markedly improved electrochemical performance. Its reversible discharge capacity was 766 mAh g −1 at 1 A g −1 , and it also maintained as 469 mAh g −1 at 6 A g −1 .