Hierarchical Porous Acetylene Black/ZnFe2O4@Carbon Hybrid Materials with High Capacity and Robust Cycling Performance for Li-ion Batteries

Abstract

A hierarchical porous acetylene black/ZnFe2O4@carbon hybrid material is prepared by direct thermal decomposition of a mixture of Zn-Fe-oleate complex mixed with acetylene black and subsequent calcination that promotes the conversion reaction to generate ZnFe2O4 nanoparticles. In the hybrid structure, well-dispersed ZnFe2O4 nanoparticles are anchored on the acetylene black substrate and these nanocomposites are further covered and interlinked by amorphous carbon layer, resulting in self-assembly into large hierarchical porous granules. Utilization of the conductive carbon in the nanocomposite can enable better electrons transfer. In addition, this unique structure effectively prevents the aggregation of the ZnFe2O4 nanoparticles and buffers the large volume change of the active material as well as avoiding undesired side effect of the electrode. The hierarchical porous acetylene black/ZnFe2O4@carbon nanocomposite exhibits favorable electrochemical performance, including high reversible capacity retention, good cycling stability, and high rate performance, which suggests that this rational hybrid material has alluring prospect for superior Li-ion batteries.