Multiscale
Assembly of Grape-Like Ferroferric Oxide and Carbon Nanotubes: A Smart
Absorber Prototype Varying Temperature to Tune Intensities
Ming-Ming Lu
Mao-Sheng Cao
Yi-Hua Chen
Wen-Qiang Cao
Jia Liu
Hong-Long Shi
De-Qing Zhang
Wen-Zhong Wang
Jie Yuan
10.1021/acsami.5b05595.s001
https://acs.figshare.com/articles/journal_contribution/Multiscale_Assembly_of_Grape_Like_Ferroferric_Oxide_and_Carbon_Nanotubes_A_Smart_Absorber_Prototype_Varying_Temperature_to_Tune_Intensities/2135782
Ideal electromagnetic attenuation
material should not only shield the electromagnetic interference but
also need strong absorption. Lightweight microwave absorber with thermal
stability and high efficiency is a highly sought-after goal of researchers.
Tuning microwave absorption to meet the harsh requirements of thermal
environments has been a great challenge. Here, grape-like Fe<sub>3</sub>O<sub>4</sub>-multiwalled carbon nanotubes (MWCNTs) are synthesized,
which have unique multiscale-assembled morphology, relatively uniform
size, good crystallinity, high magnetization, and favorable superparamagnetism.
The Fe<sub>3</sub>O<sub>4</sub>-MWCNTs is proven to be a smart microwave-absorber
prototype with tunable high intensities in double belts in the temperature
range of 323–473 K and X band. Maximum absorption in two absorbing
belts can be simultaneously tuned from ∼−10 to ∼−15
dB and from ∼−16 to ∼−25 dB by varying
temperature, respectively. The belt for reflection loss ≤−20
dB can almost cover the X band at 323 K. The tunable microwave absorption
is attributed to effective impedance matching, benefiting from abundant
interfacial polarizations and increased magnetic loss resulting from
the grape-like Fe<sub>3</sub>O<sub>4</sub> nanocrystals. Temperature
adjusts the impedance matching by changing both the dielectric and
magnetic loss. The special assembly of MWCNTs and magnetic loss nanocrystals
provides an effective pathway to realize excellent absorbers at elevated
temperature.
2015-09-02 00:00:00
MWCNT
tunable microwave absorption
Smart Absorber Prototype
Tuning microwave absorption
Tune IntensitiesIdeal electromagnetic attenuation material
dB
3O
X band
nanocrystal
Fe
impedance
Lightweight microwave absorber