Influence of morphologies on the electromagnetic and microwave absorbing properties of nickel cobaltite

Different morphologies of nickel cobaltite (NiCo2O4) nanoparticles and nanosheets were synthesized through a simple hydrothermal method and the morphologies of NiCo2O4 can be adjusted only by changing the solvent. The electromagnetic and microwave absorbing properties of NiCo2O4 with different morphologies were studied and its electromagnetic loss mechanism was illustrated. Compared with NiCo2O4 nanoparticles, NiCo2O4 nanosheets have higher electromagnetic constant due to the larger surface, which enhanced its interfacial polarization and dielectric loss ability. For NiCo2O4 nanosheets, the minimum reflection loss value was - 11 dB with the thickness of 1.4 mm, and the reflection loss value below - 5 dB can be got with the thickness from 1.4 to 1.7 mm, the results indicated that the obtained NiCo2O4 nanosheets are a kind of potential electromagnetic wave absorbent with good absorbing properties and lightweight.