Lightweight PPy aerogel adopted with Co and SiO2 nanoparticles for enhanced electromagnetic wave absorption

Abstract Lightweight nanocomposites consisting of magnetic and dielectric units aroused intensive interest as potential high performance electromagnetic wave absorbing materials. In this work, we report a facile and efficient method to fabricate (Co, SiO2)/PPy composites with tunable electromagnetic properties. The absorbing properties and effective absorbing bandwidth can be regulated by controlling the content of SiO2 in composites. The composite shows a maximum reflection loss (RL) of -65.31 dB at 11.12 GHz with a thickness of 3.002 mm when SiO2 being 22 wt.%. The effective absorbing bandwidth reaches up to 5.1 GHz (8.91–14.01 GHz), which covers the entire X band (8–12 GHz). The improved impedance matching, high interfacial polarization and complex electromagnetic synergy in the composites are the key factors giving rise to the higher efficient absorption. The PPy aerogel-based nanocomposites with controllable absorption performance, lower density and strong environmental adaptability will become attractive candidates as advanced microwave absorbing materials.