Bio-inspired fabrication of hierarchical Ni–Fe–P coated skin collagen fibers for high-performance microwave absorption

In the present investigation, skin collagen fiber (CF) with a well defined hierarchical 3D fibrous structure was employed for the bio-inspired fabrication of high-performance microwave absorption materials. The hierarchical 3D structure of the CF was retained in the CF@Ni–Fe–P composites, and the formation of the Ni–Fe–P coating on the CF surface was identified by XRD and XPS analysis. Based on the electromagnetism parameter measurements, the maximum reflection loss (RL) of the CF@Ni–Fe–P composites reached −31.0 dB, and the width of the absorption band where reflection loss values exceeded −10.0 dB covered the whole Ku-band and some parts of the X-band (9.5–18.0 GHz). The complex permittivity and complex permeability measurements indicated that electronic loss and magnetic loss were involved in the CF@Ni–Fe–P composites for microwave absorption. In addition, due to the magnetic properties of the Ni–Fe–P coating, these CF@Ni–Fe–P composites exhibited excellent magnetic characteristics with high saturation magnetization and low coercivity values. The present investigation indicates a new possibility for the bio-matrix-based fabrication of high-performance microwave absorbing materials with lightweight and efficient absorption properties.