Hierarchical aggregation structure regulation and electromagnetic loss mechanism of cross-linked polyaniline in polymer wave absorbers

Abstract

Frequency-specific electromagnetic wave absorbent materials are a key solution to the problem of multi-band electromagnetic pollution. Traditional absorbent materials often exhibit abrupt changes in electrical parameters due to factors such as threshold over-permeation. Few studies have established a strong correlation between the microscopic structure of these materials and their effective absorption frequency (EAF) ranges, making precise linear control difficult. Therefore, it is essential to explore new absorbent materials with adjustable structures closely linked to their electrical parameters. In this work, we focused on easily modifiable conductive polymer composites, producing a series of polymer-magnetic oxide absorbing materials with crosslinking degrees and magnetic properties that can be linearly adjusted. By optimizing their microstructure, we enhanced their impedance matching capabilities. Ultimately, we developed an efficient absorbent material with tunable absorption effects, specifically, the P-1.0Co₃O₄ sample achieved an effective absorption bandwidth of 6.64 GHz at a thickness of only 1.3 mm, with tunable EAF ranging from 10.9 GHz to 18.0 GHz. While full-band adjustability was not realized, this work provides significant theoretical guidance and engineering application value for developing band-specific absorbent materials.