Graphene has shown great potential in microwave absorption(MA) owing to its high surface area, low density,tunable electrical conductivity and good chemical stability.To fully realize graphenes& MA ability, the mi...Graphene has shown great potential in microwave absorption(MA) owing to its high surface area, low density,tunable electrical conductivity and good chemical stability.To fully realize graphenes& MA ability, the microstructure of graphene should be carefully addressed. Here we prepared graphene microflowers(Gmfs) with highly porous structure for high-performance MA filler material. The efficient absorption bandwidth(reflection loss B-10 dB) reaches 5.59 GHz and the minimum reflection loss is up to -42.9 dB, showing significant increment compared with stacked graphene. Such performance is higher than most graphene-based materials in the literature. Besides, the low filling content(10 wt%) and low density(40–50 mg cm^(-3))are beneficial for the practical applications. Without compounding with magnetic materials or conductive polymers,Gmfs show outstanding MA performance with the aid of rational microstructure design. Furthermore, Gmfs exhibit advantages in facile processibility and large-scale production compared with other porous graphene materials including aerogels and foams.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 21325417 and 51533008)National Key R&D Program of China (No. 2016YFA0200200)Fundamental Research Funds for the Central Universities (2017XZZX008-06)
文摘Graphene has shown great potential in microwave absorption(MA) owing to its high surface area, low density,tunable electrical conductivity and good chemical stability.To fully realize graphenes& MA ability, the microstructure of graphene should be carefully addressed. Here we prepared graphene microflowers(Gmfs) with highly porous structure for high-performance MA filler material. The efficient absorption bandwidth(reflection loss B-10 dB) reaches 5.59 GHz and the minimum reflection loss is up to -42.9 dB, showing significant increment compared with stacked graphene. Such performance is higher than most graphene-based materials in the literature. Besides, the low filling content(10 wt%) and low density(40–50 mg cm^(-3))are beneficial for the practical applications. Without compounding with magnetic materials or conductive polymers,Gmfs show outstanding MA performance with the aid of rational microstructure design. Furthermore, Gmfs exhibit advantages in facile processibility and large-scale production compared with other porous graphene materials including aerogels and foams.