Seed-assisted synthesis of Co3O4@α-Fe2O3 core–shell nanoneedle arrays for lithium-ion battery anode with high capacity

Abstract

A novel hierarchical Co₃O₄@α-Fe₂O₃ core–shell nanoneedle array (Co₃O₄@α-Fe₂O₃ NAs) on nickel foam substrate is synthesized successfully by a stepwise, seed-assisted, hydrothermal approach. This composite nanostructure serving as an anode material for lithium-ion batteries (LIBs) is advantageous in providing large interfacial area for lithium insertion/extraction and short diffusion pathways for electronic and ionic transport. The results show that a high initial discharge capacity of 1963 mA h g⁻¹ at 120 mA g⁻¹ was obtained by using these hierarchical Co₃O₄@α-Fe₂O₃ NAs heterostructures as an anode, and is retained at 1045 mA h g⁻¹ after 100 cycles, better than that of pure Co₃O₄ nanoneedle arrays (Co₃O₄ NAs) and α-Fe₂O₃ film grown under similar conditions, indicating a positive synergistic effect of the material and structural hybridization on the enhancement of the electrochemical properties. The fabrication strategy presented here is facile, cost-effective, and scalable, which opens new avenues for the design of optimal composite electrode materials with improved performance.