Core-Shell Structured SiO2@NiFe LDH Composite for Broadband Electromagnetic Wave Absorption

In this work, a novel core-shell structure material, NiFe layered double hydroxide (NiFe LDH) loaded on SiO2 microspheres (SiO2@NiFe LDH), was synthesized by a one-step hydrothermal method, and the spontaneous electrostatic self-assembly process. The morphology, structure, and microwave absorption properties of SiO2@NiFe LDH nanocomposites with different NiFe element ratios were systematically investigated. The results show that the sample of SiO2@NiFe LDH-3 nanocomposite has excellent microwave absorption properties. It exhibits broadband effective absorption bandwidth (RL < −10 dB) of 8.24 GHz (from 9.76 GHz to 18.0 GHz) and the reflection loss is −53.78 dB at the matched thickness of 6.95 mm. It is expected that this SiO2@NiFe-LDH core-shell structural material can be used as a promising non-precious, metal-based material microwave absorber to eliminate electromagnetic wave contamination.