Affiliation of Author(s):材料科学与技术学院
Journal:PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
Key Words:electromagnetic wave absorption interfacial polarization nanoporous carbon NiO/Ni/graphene yolk-shell structures
Abstract:Hierarchical yolk-shell nanostructure (NiO/Ni/GN@Air@NiO/Ni/GN) derived from Ni-based metal-organic frameworks (Ni-MOFs) is synthesized by solvothermal reactions. After successive carbonization and oxidation treatments, hierarchical NiO/Ni nanocrystals covered with a graphene shell are obtained with the yolk-shell nanostructure intact. The NiO/Ni/GN@Air@NiO/Ni/GN composites are characterized by X-ray diffraction, scanning electron microscopy, and transmission electron micro-scopy. The results indicate that the NiO/Ni/GN@Air@NiO/Ni/GN composites exhibit superior electromagnetic wave absorption properties. A minimum reflection loss (RLmin) of -34.5 dB is obtained at 17.2 GHz with the thin thickness of 1.7 mm. In addition, the best microwave absorption properties are achieved with a 2.0 mm absorber layer (RLmin = -22.5 dB, bandwidth of 6.0 GHz). The outstanding absorption ability may arise from the unique yolk-shell structure and nanoporous carbon, which can tune the dielectric of the NiO/Ni/GN@Air@NiO/Ni/GN composites to acquire good impedance matching. Moreover, the interspaces can induce interfacial polarization and multiple reflections.
ISSN No.:0934-0866
Translation or Not:no
Date of Publication:2017-05-01
Co-author:梁小会,权斌,孙延生,张亚男,马建娜,李道冉,张豹山,都有为
Correspondence Author:jiguangbin