کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1604995 | 1516208 | 2016 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Transform between the permeability and permittivity in Ni@CCNbC nanocomposites with enhanced microwave absorption properties Transform between the permeability and permittivity in Ni@CCNbC nanocomposites with enhanced microwave absorption properties](/preview/png/1604995.png)
• Ni@CCNbC nanocomposites are prepared by arc discharge method.
• Ni@CCNbC nanocomposites exhibit large permittivity and enhanced dielectric loss.
• An anomalously electromagnetic resonance appears at ∼12 GHz.
• An unusual energy transfers from the permeability to permittivity at ∼12 GHz.
• The RL value reaches −40.4 dB at 8.48 GHz with the absorbent thickness of 3.2 mm.
We report the microwave absorption properties of a composite system comprising of core-shell structured Ni@C nanocapsules, defective onion-like carbon nanoparticles and NbC nanoparticles. Compared with Ni@C nanocapsules, the Ni@CCNbC nanocomposites exhibit large permittivity, enhanced dielectric loss and three Debye dipolar relaxations. An anomalous electromagnetic resonance in the Ni@CCNbC/paraffin system appears at ∼12 GHz, revealing an energy transform from the permeability to permittivity. The reflection loss value of the Ni@CCNbC/paraffin composites reaches −40.4 dB at 8.48 GHz with the absorbent thickness of 3.2 mm. Experimental results coupled with theoretical calculations by the Cole-Cole equation and the delta function standing for the electromagnetic matching degree further reveal that the good microwave absorption originates from the enhanced dielectric loss and improved electromagnetic matching.
Journal: Journal of Alloys and Compounds - Volume 685, 15 November 2016, Pages 50–57