Highly graphitized carbon nanosheets with embedded Ni nanocrystals as anode for Li-ion batteries
A C/Ni composite was prepared via thermal decomposition of a nickel oleate complex at 700 °C, yielding disperse Ni nanocrystals with an average size of 20 nm, encapsulated by carbon nanosheets as deduced from transmission electron microscopy (TEM) images and confirmed from X-ray photoelectron spectr...
| Autores: | , , , , , |
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| Formato: | artículo |
| Fecha de publicación: | 2020 |
| País: | España |
| Recursos: | Universidad de Castilla-La Mancha |
| Repositorio: | RUIdeRA. Repositorio Institucional de la UCLM |
| OAI Identifier: | oai:ruidera.uclm.es:10578/40796 |
| Acesso em linha: | https://hdl.handle.net/10578/40796 |
| Access Level: | acceso abierto |
| Palavra-chave: | Anode Graphene nanosheets Lithium batteries Nickel nanoparticles |
| Resumo: | A C/Ni composite was prepared via thermal decomposition of a nickel oleate complex at 700 °C, yielding disperse Ni nanocrystals with an average size of 20 nm, encapsulated by carbon nanosheets as deduced from transmission electron microscopy (TEM) images and confirmed from X-ray photoelectron spectroscopy (XPS). Furthermore, the X-ray diffraction pattern revealed a good ordering of the carbon layers, forced by the Ni encapsulation to adopt a bending structure. Considering the close interaction between the graphitized framework and the metallic nanoparticles we have studied the properties of the composite as an anode for Li-ion batteries. Compared with other nanostructured synthetic carbons, this carbon composite has a low voltage hysteresis and a modest irreversible capacity value, properties that play a significant role in its behaviour as electrodes in full cell configuration. At moderate rate values, 0.25 C, the electrode delivers an average capacity value around 723 mAh·g-1 on cycling, among the highest values so far reported for this carbon type. At higher rate values, 1 C, the average capacity values delivered by the cell on cycling decrease, around 205 mAh·g-1, but it maintains good capacity retention, a coulombic efficiency close to 100% after the first cycles and recovery of the capacity values when the rate is restored from 3 to 0.1 C. |
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