Revealing the influence of conversion-type Co3O4 dimensionality on cyclic and rate performance for lithium storage

Cobalt tetraoxide (Co 3 O 4 ) is regarded as a promising anode material for Li-ion batteries owing to its high theoretical capacity (890 mAh g −1 ), simple preparation, and controllable morphology. Nanoengineering has been proven to be an effective method for producing high-performance electrode materials . However, systematic research on the influence of material dimensionality on battery performance is lacking. Herein, we prepared Co 3 O 4 with various dimensionalities (one-dimensional (1D) Co 3 O 4 nanorod (NR), two-dimensional (2D) Co 3 O 4 nanosheet (NS), three-dimensional (3D) Co 3 O 4 nanocluster (NC), and 3D Co 3 O 4 nanoflower (NF)) using a simple solvothermal heat treatment method, and their morphologies were controlled by varying the precipitator type and solvent composition . The 1D Co 3 O 4 NR and 3D samples (3D Co 3 O 4 NC and 3D Co 3 O 4 NF) exhibited poor cyclic and rate performances, respectively, while the 2D Co 3 O 4 NS exhibited the best electrochemical performance . The mechanism analysis revealed that the cyclic stability and rate performance of the Co 3 O 4 nanostructures are closely related to their intrinsic stability and interfacial contact performance, respectively, and the 2D thin-sheet structure can achieve an optimal balance between the two, resulting in the best performance. This work presents a comprehensive study on the effect of dimensionality on the electrochemical performance of Co 3 O 4 anodes, providing a new concept for the nanostructure design of conversion-type materials.