Phase engineering reinforced multiple loss network in apple tree-like liquid metal/Ni-Ni3P/N-doped carbon fiber composites for high-performance microwave absorption

Abstract

Microscopic manipulation and appropriate multicomponent design are still challenging for keeping up with the future development direction for high-efficient electromagnetic wave (EMW) absorbers with unique structure. In this work, apple tree-like Galinstan/Ni-Ni3P/N-doped carbon fiber composites were successfully fabricated through electroless plating and subsequent pyrolysis process. N-doped carbon fiber, derived from silkworm cocoons, is employed as one-dimensional skeleton to generate conductive network and dipole polarization due to intrinsic existence of amino acids. The phase engineering from amorphous Ni-P to crystalline Ni-Ni3P create countless heterogeneous interfaces, double conductive pathway and enhanced permeability, thus promoting the dielectric/magnetic response with incident EMW. And the introduction of the Galinstan is beneficial to manipulate the permittivity and impedance matching degree. By tailoring pyrolysis temperature, the optimal composite produces outstanding EMW absorption performance at the thickness of only 2.05 mm, whose strongest reflection loss can reach −51.73 dB with an effective absorption bandwidth ranging from 9.7 to 13.5 GHz. Besides, CST simulation also evidently show the suppression (13.7 dBm2) with incident EMW of samples in the actual environment. This thorough exploration of the phase engineering and bio-inspired construction of multicomponent system develops a referable route toward the high-efficient EMW absorbers.