Modifying the CNTs with high dielectric loss NiCo₂O₄ to enhance the electromagnetic wave absorption properties

Decorating the CNTs with dielectric loss material is an effective means of enhancing electromagnetic wave absorption properties. In this work, we synthesized high dielectric loss NiCo₂O₄ nanoparticles on CNTs through hydrothermal method. By adjusting hydrothermal time, the NiCo₂O₄/CNTs with different NiCo₂O₄ content were obtained. The nucleation and growth of NiCo₂O₄ nanoparticles would cause a lot of defects and heterogeneous interfaces on CNTs, which influences the conduction loss and polarization loss of CNTs. Therefore, adjusting the content of NiCo₂O₄ in CNTs is an efficient path to enhance its absorbing performance. When the content of NiCo₂O₄ is 45.05 wt%, the reflection loss of NiCo₂O₄/CNTs reaches −43.2 dB, and the effective absorption bandwidth can be up to 3.3 GHz. It proves that NiCo₂O₄/CNTs has potential to be a high quality absorbing agent.