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Updated: Aug 6, 2026

Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
Octahedral Ni3+ Substitution-Induced D-Band Center Modulation Enables Fast and Fully Reversible Conversion Kinetics
Ni Fang1,2, Huihui Yuan1,2, Xiaorong Dong1,2
1The State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, P.R. China.
Researchers improved sodium storage in conversion-type sulfides by substituting nickel ions. This modification enhances redox kinetics and reversibility, leading to high capacity and stable cycling performance for advanced battery applications.
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- Conversion-type sulfides show promise for high-capacity sodium storage.
- Key limitations include sluggish redox kinetics, incomplete reconversion, and volume expansion.
Purpose of the Study:
- To address the limitations of conversion-type sulfides for sodium storage.
- To enhance electrochemical performance through targeted material modification.
Main Methods:
- Synthesized Ni(Co1-xNix)2S4 (NNCS) hollow nanospheres with Ni3+ enriched in octahedral sites.
- Investigated electronic structure changes using d-band center and d-p hybridization analysis.
- Performed ex situ characterization (HRTEM, SAED, XPS, XRD) to study conversion/reconversion processes.
- Evaluated electrochemical performance, including cycling stability and Coulombic efficiency.
Main Results:
- NNCS exhibited a downshifted d-band center (-1.80 eV) and narrowed d-p energy separation (0.103 eV).
- Facilitated fast and reversible conversion reactions with nearly complete reconversion.
- Achieved high initial Coulombic efficiency (91%) and excellent cycling stability (632 mAh g-1 after 800 cycles at 5 A g-1).
- Demonstrated sustained capacity (500 mAh g-1 after 900 cycles at 10 A g-1) and high retention in a full cell.
Conclusions:
- Octahedral-site Ni3+ substitution effectively mitigates limitations in conversion-type sulfides.
- The modified NNCS material offers superior sodium storage capacity, kinetics, and cycling stability.
- This approach presents a viable strategy for developing high-performance sodium-ion battery electrodes.
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