Remarkable microwave absorption performance of ultralight graphene-polyethylene glycol composite aerogels with a very low loading ratio of graphene

Graphene/polyethylene glycol (GPEG) composite aerogels were fabricated by the reduction-assembly of graphene oxide (GO) in polyethylene glycol 400 (PEG400) and the following freeze-drying process. PEG400 can effectively avoid the agglomeration of graphene sheets and adjust the permittivity of GPEGs. These GPEGs show an outstanding improvement on microwave absorption performance when the additive amount of GO is 5-25 wt %. The minimum reflection loss (Fa) can reach -43.2 dB at 13.8 GHz, and the effective absorption bandwidth (RL < -10 dB) was 5.30 GHz (9.6-14.9 GHz) with the absorber thickness of 2.35 mm when the additive amount of GO in absorber is only 7.5 wt%. These composite aerogels still maintain an ultralight nature (the density of 18.5-19.8 mg/cm(3)). This work provides a facile preparation method to fabricate an exceptional microwave absorption material which possesses lightweight, economy and the high-efficient microwave absorption property.