Loss mechanism and microwave absorption properties of hierarchical NiCo₂O₄nanomaterial

Understanding the loss mechanism of microwave absorption is of great significance for the design and fabrication of low-cost, high-efficient and light-weight microwave absorbing materials. In this study, the microwave absorption of a hierarchical NiCo 2 O 4 nanomaterial synthesized via a hydrothermal method and a subsequent annealing process was investigated in detail. The effects of the annealing temperature on the phase evaluation and microwave absorption properties were also investigated to reveal the microwave loss mechanism of NiCo 2 O 4 nanostructures. The results show that the Debye relaxation and superior electric conductivity of NiCo 2 O 4 are beneficial to its excellent microwave absorption performance. This study will be useful for the fundamental understanding of microwave absorption in NiCo 2 O 4 nanomaterial, and for the design of a novel microwave absorbent.