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In this study, a facile and cost‐effective hydrothermal approach is employed to synthesize a mesoporous NiCo2O4/Co3O4 nanocomposite with nanowire morphology by using polyvinyl pyrrolidone as structure‐directing agent. The obtained NiCo2O4/Co3O4 nanocomposite shows better electrochemical performance than pure NiCo2O4 due to mainly two reasons: i) a strong synergistic effect between NiCo2O4 and Co3O4, which enhances the Li+ diffusion rate as well as lower the charge‐transfer resistance, and ii) the involvement of Co3O4 to contribute to the total capacity due to its high electrochemical activity. However, the performance of a NiCo2O4/Co3O4 nanocomposite electrode starts degrading after 400 cycles while pure NiCo2O4 maintains steady performance. Since the NiCo2O4/Co3O4 nanocomposite sample shows high porosity, it is believed that the obtained nanowire morphology cannot tolerate volume variations, which are generally triggered off during repeated Li+ (de‐)insertion at long‐term cycling. Therefore, the obtained results bring new insights in terms that there is a sweet spot between Li+ diffusion and high porosity in utilizing Co3O4 within a nanocomposite. This study is of guidance to shed the light on the research of ternary transition metal oxide nanocomposite materials for lithium‐ion batteries.

In this work, the hollow mesoporous CuO nanotubes are synthesized using a surfactant‐assisted soft template approach. It is believed that the surfactant used during the synthesis provides a skeleton for the rearrangement of nanoparticles, resulting in the formation of hollow nanotubes. Furthermore, the sample becomes mesoporous during the calcination at 500 °C due to the removal of the surfactant template. On the other hand, the porous nanostructure efficiently improves the reaction kinetics of the electrode material, which offers excellent electrochemical performance. The obtained hollow mesoporous CuO nanotube electrode manifests high Li‐ion storage such as ∼253 mAh g−1 at 1 C and 118 mAh g−1 at 3 C after 150 cycles. It is significant to highlight that the current synthesis process is straightforward, affordable, time‐efficient and environment friendly as compared to tedious physical approaches. In addition, the proposed strategy in this work also demonstrates a window for the development of new advanced nanomaterials for post‐lithium‐ion battery applications.

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