Electrosprayed graphene films decorated with bimetallic (zinc-iron) oxide for lithium-ion battery anodes

Bimetallic (zinc-iron) oxide with a pillar-like morphology is decorated over graphene films. The electrosprayed composite demonstrates good electrochemical performance as an anode material for lithium-ion batteries. Scanning and transmission electron microscopy images confirm the effective decoration of graphene sheets with bimetallic Zn-Fe oxide particles. The composite shows a high capacity of 1601 mAh⋅g⁻¹ at 100 mA·g⁻¹ owing to its unique layer-particle morphology. The anode material exhibits excellent capacity retention of 77% (∼1235 mAh⋅g⁻¹ at 100 mA·g⁻¹) after 100 cycles, due to buffering of volumetric strain in the metal oxide by flexible conductive graphene sheets. Zinc forms an alloy with the lithium ions, and the graphene sheets prevent particle agglomeration, keeping transport distances within particles small. Thus, synthesizing a composite of graphene with Zn-Fe oxides via electrospray deposition is a promising method for preparing high-performance anode materials for lithium-ion batteries.