A facile hydrolysis-coupled redox (HCR) reaction followed by postheating reduction has been designed to prepare unique 3D Cu/Fe3O4 core–shell nanorod array anodes. Fe2+ ions from fresh FeSO4 solution have been hydrolyzed and oxidized to form an Fe(OH)3 shell on the surface of Cu(OH)2 nanorods; meanwhile the resulting acidic environment induces the reduction of Cu(OH)2 to Cu2O, which realizes an unusual redox reaction between Fe2+ ions and Cu(OH)2. The reaction procedure and thermodynamics possibility between Fe2+ ions and Cu(OH)2 nanorod arrays are discussed from the aspect of electrode potentials. After postheating reduction in Ar/H2, the obtained 3D architecture of Cu current collector serves as a stout support for the Fe3O4 shell to form nanorod array anodes without using any binders or conducting agents. The resulting highly stable core–shell structure facilitates rapid and high-throughput transport pathways for ions/electrons and allows better accommodation of volume change during the repeated lithiation/delithiation. Its application as anodes in combination with LiNi0.5Mn1.5O4 cathodes for full cells demonstrates superior rate capability, enhanced energy density, and long cycling life.
Gu, H., Zhang, Y., Huang, M., Chen, F., Yang, Z., Fan, X., Li, S., Zhang, W., Yang, S., & Li, M. (2017). Hydrolysis-Coupled Redox Reaction to 3D Cu/Fe3O4 Nanorod Array Electrodes for High-Performance Lithium-Ion Batteries. Inorganic Chemistry, 56(14), 7657–7667. https://doi.org/10.1021/acs.inorgchem.7b00112