Hierarchically structured mesoporous bimetallic oxides as a potential anode material for rechargeable lithium batteries

Transition metal oxides have been considered as a promising class of electrode materials in electrochemical energy storage devices and possess better capacities than mono-metal oxides. For the development of lithium-ion energy storage systems, the architecture of the electrode material plays a vital role. Herein, we have synthesized one-dimensional (1D) mesoporous NiCo₂O₄ hollow nanofibers (HNFs) with the flaky architecture of its surface using the lab waste filter paper as a template during the hydrothermal process. The NiCo₂O₄ HNFs show good electrochemical properties such as initial discharge capacity of 1702 mAh g⁻¹ with the coulombic efficiency of 82% at a current density of 100 mA g⁻¹, in comparison to NiCo₂O₄ nanospheres (NSs) delivering an initial discharge capacity of 1204 mAh g⁻¹ with the coulombic efficiency of 74%. The HNFs with interconnected flaky surface provides a large number of lithium storage sites and also shortens the diffusion path for both the lithium ions and electrons and thereby enhancing the performance of Li-ion batteries.