▎ 摘　　要

As a novel lightweight absorber, different ionic liquid doped graphene (IG) with high electromagnetic wave (EMW) absorption efficiency and wide absorption bandwidth was synthesized using a facile one-step physical adsorption strategy of pi-pi stacking. Defects and conductive networks formed in IG improve the conduction loss, polarization, and multiple reflecting/scattering of IG, leading to significantly enhanced EMW absorption properties. The 1-aminoethyl-3-methylimidazolium bromide ionic liquid doped graphene with an ultra-low filler loading of only 5 wt% exhibits the minimum reflection loss of - 44.9 dB at 2.2 mm and effective absorption bandwidth (exceeding - 10 dB) up to 5.8 GHz with a thin thickness of 1.9 mm. This work provides a feasible approach and basic absorption mechanisms for designing and fabricating novel graphene-based absorbers with high-performance EMW absorption.