Conversion-reaction induced charge storage mechanisms of transition metal sulphides have received considerable interest in designing high-capacity electrodes for electrochemical energy storage devices. However, their low conductivity and structural degradation during cycling limit their applications as energy storage devices. A combination of different nickel sulphide phases tailored with carbon nanostructures is suggested to address these limitations. Herein, a facile, two-step approach is demonstrated for fabricating a hybrid electrode, consisting of trinickel disulphide (Ni3S2) formed on a metallic Ni nanoparticle supported by vertical carbon nanotubes (VCN) backbone in the form Ni3S2/Ni@VCN. Ni3S2/Ni@VCN electrodes were tested as anode for lithium-ion batteries, and the electrode featured outstanding lithium-storage capabilities with a high reversible capacity (1113 mAh g−1 after 100 cycles at 100 mA g−1), excellent long-term cycling stability (770 mAh g−1 after 500 cycles at 200 mA g−1), and good rate capability. The resulting electrode performance is one of the best Li-ion storage capabilities in the Ni3S2-type anode materials described. A unique “broccoli-like” structure of polycrystalline Ni3S2 capped on conductive VCN backbone helps the interface storage process and boosts lithium storage performance.
- Binder-free electrode
- Hierarchical structures
- Lithium-ion batteries
- Vertical carbon nanostructures