Affiliation:
1. School of Rare Earths University of Science and Technology of China Hefei 230026 P. R. China
2. Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou 341000 P. R. China
3. National Engineering Research Center of Green Recycling for Strategic Metal Resources Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 P. R. China
Abstract
AbstractNanocomposites with hierarchical pore structure hold great potentials for applications in the field of microwave‐absorbing materials because of their lightweight and high‐efficiency absorption properties. Herein, M‐type barium ferrite (BaM) with ordered mesoporous structure (M‐BaM) is prepared via a sol–gel process enhanced by mixed anionic and cationic surfactants. The surface area of M‐BaM is enhanced almost ten times compared with BaM together with 40% reflection loss enhancing. Then M‐BaM compounded with nitrogen‐doped reduced graphene oxide (MBG) is synthesized via hydrothermal reaction in which the reduction and nitrogen doping of graphene oxide (GO) in situ occur simultaneously. Interestingly, the mesoporous structure is able to provide opportunity for reductant to enter the bulk M‐BaM reducing its Fe3+ to Fe2+ and further forms Fe3O4. It requires an optimal balance among the remained mesopores in MBG, formed Fe3O4, and CN in nitrogen‐doped graphene (N‐RGO) for optimizing impedance matching and greatly increasing multiple reflections/interfacial polarization. MBG‐2 (GO:M‐BaM = 1:10) achieves the minimum reflection loss of −62.6 dB with an effective bandwidth of 4.2 GHz at an ultra‐thin thickness of 1.4 mm. In addition, the marriage of mesoporous structure of M‐BaM and light mass of graphene reduces the density of MBG.
Funder
Chinese Academy of Sciences
National Key Research and Development Program of China
National Natural Science Foundation of China
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry