Hierarchical NiCo₂O₄ Micro- and Nanostructures with Tunable Morphologies as Anode Materials for Lithium- and Sodium-Ion Batteries

NiCo2O4 microrods with open structures are successfully synthesized using a solvothermal method. Compared with those of dense microspheres, the one-dimensional (1D) porous microrods show much higher capacities and stability for both Li- and Na-ion batteries due to the 1D open structure facilitating fast ion transport and buffering volumetric change during charge/discharge. This work demonstrates that the electrochemical performance of NiCo2O4 is highly dependent on morphologies of the active material.