Selective microwave absorption of iron-rich carbon nanotube composites.
We report on high selectivity of microwave absorption by controlling the concentration of carbon nanotubes in polymer composites and matching the dielectric loss and magnetic loss through encapsulation of crystalline Fe nanorods inside nanotubes. The reflection loss reached more than 10 dB (> 90% absorption) by loading nanotubes at concentrations of 1 wt% to 10 wt% into the composites, and the frequencies corresponding to the maximum loss can be tailored throughout the range of 2 to 18 GHz by changing the concentration. A maximum absorption capability (75 dB x GHz) was observed at a CNT loading of about 4.5 wt%. The crystalline structure of encapsulated Fe nanorods can be modified to enhance the reflection loss. Control of absorption selectivity by modifying the structure and concentration of nanoscale fillers could facilitate potential higher-frequency applications (e.g., radar absorbing) of nanocomposites.
Gui
Xuchun
X
Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China.
Wang
Kunlin
K
Cao
Anyuan
A
Wei
Jinquan
J
Lv
Ruitao
R
Kang
Feiyu
F
Shu
Qinke
Q
Jia
Yi
Y
Wu
Dehai
D