Fabrication of core-shell Ni@C@PANI nanocomposite-based bionic coating with multi-bands EWM adaptability inspired by porous structure of pachliopta aristolochiae wings

Abstract

Due to the Planck-Rozanov limit, stealth materials are prevented from realizing ultra-wideband absorption at deep sub-wavelength thickness. Herein, inspired by the absorption model of Pachliopta aristolochiae wings porous structure, a core-shell Ni@C@PANI nanometer powder-based bionic coating with multi-bands EWM adaptability was designed. The synergistic effect of excellent impedance matching, significant attenuation system, conduction loss, dipole polarization, interface polarization and good magnetic loss endow the hierarchical core-shell Ni@C@PANI nanocomposite with excellent EMW absorption properties. Additionally, the absorption of EMW in the low frequency bands mainly originates from the multiple reflection of EMW by the bionic porous structure. At high frequencies, in addition to resonance and reflection, the hole edges convert the linearly polarized electric field vector into a vortex form, thus dissipating the magnetic field energy. Consequently, a minimum reflection loss (RL) of −50.83 dB with a matching frequency of 16.5 GHz is achieved, and the EBA is as wide as 14.75 GHz (3.25–18 GHz), covering all C, X, Ku bands and part of S band. This discovery provides a way for using natural model to break the Plank-Rozanov limit to develop new-type bionic coating with multi-bands EMW adaptability.