Microwave absorption and mechanical properties of La(NO3)3-doped multi-walled carbon nanotube/polyvinyl chloride composites

Composites that effectively absorb microwave in the frequency range of 2–18 GHz have been strongly demanded during the past decades. To enhance the absorption of microwave, composites are generally capable of wide absorption bandwidth and low reflection loss. Here, we used La(NO3)3-doped multi-walled carbon nanotubes (MWCNTs) as absorber and polyvinyl chloride (PVC) as matrix to fabricate MWCNT-La(NO3)3/PVC composites, where La(NO3)3-doped MWCNTs broadened the absorption bandwidth and decreased the reflection loss of the composites. Due to the insertion of diamagnetic La3+, the absorbing properties of as-prepared composites were enhanced, while the mechanical properties of such composite were slightly changed. The amount of doped La(NO3)3 was experimentally optimized to be 6 wt.%.

► Carbon nanotubes doped La(NO3)3 was used for the absorber.
► The frequency range of the reflectivity became larger below − 10 dB in 2–18 GHz.
► The minimum shifted to higher frequency region by doping La(NO3)3.
► The mechanical property slightly changed compare with no La(NO3)3-doped.