Dielectric response of carbon coated TiC nanocubes at 2–18 GHz frequencies

Microwave frequency (2–18 GHz) dielectric response has been investigated in the carbon-coated cubic TiC nanoparticles embedded in paraffin matrix with different weight fractions. DC conductivity measurements showed that the TiC nanocubes/paraffin composites have a percolation threshold of about 30 wt%. Absorption property was found to be improved with increasing mass ratio in the present system, up to a mass ratio of 50 wt%. Reflection loss exceeding −20 dB in the frequency range of 6–16 GHz, with layer thicknesses from 2 to 4 mm, was found in the 50 wt% loaded sample. TiC nanocube/paraffin composite with a proper mass ratio can be very good prospective microwave absorption agent.

Research highlights▶ A novel cubic TiC nanocrystals encapsulated in cubic carbon cages have been synthesized by arc-discharge. Nanocapsules are commonly reported to have spherical forms, and very few investigations have been done on the cubic core–shell structured nanocomposite. ▶ DC conductivity for the TiC nanocubes/paraffin composites are measured with a standard four-point method using the Keithley 2400 SourceMeter. Percolation threshold of about 30 wt% was found in the present system. ▶ TiC nanocubes/paraffin composites are found to show increasing RL peak values with increasing mass ratios, without maximum around the percolation threshold. ▶ Reflection loss is calculated to be exceeding −20 dB in the frequency range of 6–16 GHz, with layer thicknesses from 2 to 4 mm, in the 50 wt% loaded sample. Carbon coated TiC nanocubes seems to be very good candidate for anti-reflective microwave absorption coating materials.