Improved lithium storage in Fe2O3 nano-particles over nano-rods morphology

Fe2O3 nano-particles and nano-rods were synthesized by hydrothermal synthesis method under different reaction conditions and then applied as anode materials for Lithium ion batteries. Microstructural analysis confirmed these two shapes and structures for Fe2O3 samples. It was noticed that the electrochemical performance of Fe2O3 is highly influenced by its particle morphology. Unexpectedly, Fe2O3 nano-particles exhibit excellent electrochemical performances as compared to nano-rods morphology, which may be due to the least micro strain, high stability of nano-particles structure, small agglomerations, etc. It is believed that the nano-particles structure provides extra reaction sites to accommodate large Li-ions, shorten the Li-ion diffusion paths to improve the electronic conductivity and offers large electrolyte/electrode contact area for fast electrochemical reactions. In contrast, the nano-rods morphology could not hold its structural integrity during the lithiation/de-lithiation reactions and collapsed only after certain number of cycles giving rise to poor electrochemical performances, as confirmed by post cycling ex-situ studies. More precisely, Fe2O3 nano-particles electrode delivered the excellent reversible capacity of 1125 mAh g(-1) and 1007 mAh g(-1) at 1C and 4C after 100 and 80 cycles, respectively, while Fe2O3 nano-rods exhibit only 113.5 mAh g(-1) at 1C and 326.7 mAh g(-1) at 4C.

Automated summary

Fe2O3 nano-particles show superior electrochemical performance compared to nano-rods as anode materials in Lithium ion batteries, attributed to their high stability, small agglomerations, and providing extra reaction sites for large Li-ions. Nano-rods morphology leads to poor electrochemical performance due to structural collapse during lithiation/de-lithiation reactions after a certain number of cycles.