Copper ferrites@reduced graphene oxide anode materials for advanced lithium storage applications

Abstract

Copper ferrites are emerging transition metal oxides that have potential applications in energy storage devices. However, it still lacks in-depth designing of copper ferrites based anode architectures with enhanced electroactivity for lithium-ion batteries. Here, we report a facile synthesis technology of copper ferrites anchored on reduced graphene oxide (CuFeO₂@rGO and Cu/CuFe₂O₄@rGO) as the high-performance electrodes. In the resulting configuration, reduced graphene offers continuous conductive channels for electron/ion transfer and high specific surface area to accommodate the volume expansion of copper ferrites. Consequently, the sheet-on-sheet CuFeO₂@rGO electrode exhibits a high reversible capacity (587 mAh g^-1 after 100 cycles at 200 mA g^-1). In particular, Cu/CuFe₂O₄@rGO hybrid, which combines the advantages of nano-copper and reduced graphene, manifests a significant enhancement in lithium storage properties. It reveals superior rate capability (723 mAh g^-1 at 800 mA g^-1; 560 mAh g^-1 at 3200 mA g^-1) and robust cycling capability (1102 mAh g^-1 after 250 cycles at 800 mA g^-1). This unique structure design provides a strategy for the development of multivalent metal oxides in lithium storage device applications.