TY  - JOUR
AU  - Meng, Fanbin
AU  - Wang, Huagao
AU  - Wei, 
AU  - Chen, Zijian
AU  - Li, Tian
AU  - Li, Chunyuan
AU  - Xuan, Yu
AU  - Zhou, Zuowan
PY  - 2018
TI  - Generation of graphene-based aerogel microspheres for broadband and tunable high-performance microwave absorption by electrospinning-freeze drying process
JO  - Nano Research
SN  - 1998-0124
SP  - 2847
EP  - 2861
VL  - 11
IS  - 5
AB  - Despite recent progress in the synthesis and application of graphene-based aerogels, some challenges such as scalable and cost-effective production, and miniaturization still remain, which hinder the practical application of these materials. Here we report a large-scale electrospinning method to generate graphene-based aerogel microspheres (AMs), which show broadband, tunable and high-performance microwave absorption. Graphene/Fe3O4 AMs with a large number of openings with hierarchical connecting radial microchannels can be obtained via electrospinning-freeze drying followed by calcination. Importantly, for a given Fe3O4: graphene mass ratio, altering the shape of aerogel monoliths or powders into aerogel microspheres leads to unique electromagnetic wave properties. As expected, the reflection loss of graphene/Fe3O4 AMs-1:1 with only 5 wt.% absorber loading reaches?51.5 dB at 9.2 GHz with a thickness of 4.0 mm and a broad absorption bandwidth (RL < -10 dB) of 6.5 GHz. Furthermore, switching to coaxial electrospinning enables the fabrication of SiO2 coatings to construct graphene/Fe3O4@SiO2 core?shell AMs. The coatings influence the electromagnetic wave absorption of graphene/Fe3O4 AMs significantly. In view of these advantages, we believe that this processing technique may be extended to fabricate a wide range of unique graphene-based architectures for functional design and applications.
UR  - https://doi.org/10.1007/s12274-017-1915-6
DO  - 10.1007/s12274-017-1915-6