Understanding Structure-Function Relationship in Hybrid Co3O4-Fe2O3/C Lithium-Ion Battery Electrodes.
A range of high-capacity Li-ion anode materials (conversion reactions with lithium) suffer from poor cycling stability and limited high-rate performance. These issues can be addressed through hybridization of multiple nanostructured components in an electrode. Using a Co3O4-Fe2O3/C system as an example, we demonstrate that the cycling stability and rate performance are improved in a hybrid electrode. The hybrid Co3O4-Fe2O3/C electrode exhibits long-term cycling stability (300 cycles) at a moderate current rate with a retained capacity of approximately 700 mAh g(-1). The reversible capacity of the Co3O4-Fe2O3/C electrode is still about 400 mAh g(-1) (above the theoretical capacity of graphite) at a high current rate of ca. 3 A g(-1), whereas Co3O4-Fe2O3, Fe2O3/C, and Co3O4/C electrodes (used as controls) are unable to operate as effectively under identical testing conditions. To understand the structure-function relationship in the hybrid electrode and the reasons for the enhanced cycling stability, we employed a combination of ex situ and in situ techniques. Our results indicate that the improvements in the hybrid electrode originate from the combination of sequential electrochemical activity of the transition metal oxides with an enhanced electronic conductivity provided by percolating carbon chains.
Institute for Frontier Materials, Deakin University , Waurn Ponds, Victoria 3216, Australia.
Irin
I
Sultana
Institute for Frontier Materials, Deakin University , Waurn Ponds, Victoria 3216, Australia.
Md Mokhlesur
MM
Rahman
Institute for Frontier Materials, Deakin University , Waurn Ponds, Victoria 3216, Australia.
Thrinathreddy
T
Ramireddy
School of Chemistry, University of New South Wales , Sydney, New South Wales 2052, Australia.
Neeraj
N
Sharma
Institute for Frontier Materials, Deakin University , Waurn Ponds, Victoria 3216, Australia.
Debasis
D
Poddar
School of Physics and Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin , Dublin 2, Ireland.
Abbas
A
Khalid
School of Physics and Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin , Dublin 2, Ireland.
Hongzhou
H
Zhang
Institute for Frontier Materials, Deakin University , Waurn Ponds, Victoria 3216, Australia.
Ying
Y
Chen
Institute for Frontier Materials, Deakin University , Waurn Ponds, Victoria 3216, Australia.|Melbourne Centre for Nanofabrication , 151 Wellington Rd., Clayton, Victoria 3168, Australia.
Alexey M
AM
Glushenkov
Li-ion batteries; cycling stability; ex situ SEM; hybrid electrodes; in situ synchrotron XRD