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Sandwich-structured nanocomposites of N-doped graphene and nearly monodisperse Fe3O4 nanoparticles as high-performance Li-ion battery anodes

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Abstract

Iron oxides have attracted considerable interest as abundant materials for high-capacity Li-ion battery anodes. However, their fast capacity fading owing to poorly controlled reversibility of the conversion reactions greatly hinders their application. Here, a sandwich-structured nanocomposite of N-doped graphene and nearly monodisperse Fe3O4 nanoparticles were developed as high-performance Li-ion battery anode. N-doped graphene serves as a conducting framework for the self-assembled structure and controls Fe3O4 nucleation through the interaction of N dopants, surfactant molecules, and iron precursors. Fe3O4 nanoparticles were well dispersed with a uniform diameter of ~15 nm. The unique sandwich structure enables good electron conductivity and Li-ion accessibility and accommodates a large volume change. Hence, it delivers good cycling reversibility and rate performance with a capacity of ~1,227 mA·h·g–1 and 96.8% capacity retention over 1,000 cycles at a current density of 3 A·g–1. Our work provides an ideal structure design for conversion anodes or other electrode materials requiring a large volume change.

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Acknowledgements

The authors would like to acknowledge financial supports from the National High-tech R&D Program of China (863 Program) (Nos. 2013AA032002 and 2015AA034601), China Iron & Steel Research Institute Group Foundation (No. SHI11AT0540A) and Advance Technology & Materials Co., Ltd Innovation Foundations (No. 2013JA02PYF).

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Authors and Affiliations

  1. Beijing Key Laboratory of Energy Nanomaterials, Advance Technology & Materials Co., Ltd, China Iron & Steel Research Institute Group, Beijing, 100081, China

    Wen Qi, Ying Wu, Chunjiang Kuang & Shaoxiong Zhou

  2. School of Materials Science and Engineering, Tianjin University, Tianjin, 300072, China

    Xuan Li & Pei Li

  3. Key Laboratory for Liquid−Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan, 250061, China

    Hui Li & Weikang Wu

  4. Department of Stationary Energy Storage, Pacific Northwest National Laboratory, Richland, Washington, 99354, USA

    Xiaolin Li

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  1. Wen Qi
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  2. Xuan Li
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Correspondence to Shaoxiong Zhou or Xiaolin Li.

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Sandwich-structured nanocomposites of N-doped graphene and nearly monodisperse Fe3O4 nanoparticles as high-performance Li-ion battery anodes

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Qi, W., Li, X., Li, H. et al. Sandwich-structured nanocomposites of N-doped graphene and nearly monodisperse Fe3O4 nanoparticles as high-performance Li-ion battery anodes. Nano Res. 10, 2923–2933 (2017). https://doi.org/10.1007/s12274-017-1502-x

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